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Background: Prior research has shown that patients with stable ischemic heart disease who undergo delayed coronary artery bypass graft (CABG) surgery face higher mortality rates than those who receive CABG within the time recommended by physicians. However, this research did not account for percutaneous coronary intervention (PCI), a widely available alternative to delayed CABG in many settings. We sought to establish whether there was a difference in mortality between timely PCI and delayed CABG., Methods: We identified 25,520 patients 60 years or older who underwent first-time non-emergency revascularization for angiographically-proven, stable left main or multi-vessel ischemic heart disease in British Columbia between January 1, 2001, and December 31, 2016. We estimated unadjusted and adjusted mortality after index revascularization or last staged PCI for patients undergoing delayed CABG compared to timely PCI., Findings: After adjustment with inverse probability of treatment weights, at three years, patients who underwent delayed CABG had a statistically significant lower mortality compared with patients who received timely PCI (4.3% delayed CABG, 13.5% timely PCI; risk ratio 0.32, 95% CI 0.24-0.40)., Interpretation: Patients who undergo CABG with delay have a lower risk of death than patients who undergo PCI within appropriate time. Our results suggest that patients who wish to receive CABG as their revascularization treatment will receive a mortality benefit over PCI as an alternative strategy., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Hardiman et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Context/objective: The risk for cardiovascular disease is amplified following spinal cord injury, but whether risk differs between the sexes remains unknown. Here, we evaluated sex differences in the prevalence of heart disease among individuals with spinal cord injury, and compared sex differences with able-bodied individuals., Design: The design was a cross-sectional study. Multivariable logistic regression analysis was conducted, using inverse probability weighting to account for the sampling method and to adjust for confounders., Setting: Canada., Participants: Individuals who participated in the national Canadian Community Health Survey., Interventions: Not applicable., Outcome Measures: Self-reported heart disease., Results: Among 354 individuals with spinal cord injury, the weighted prevalence of self-reported heart disease was 22.9% in males and 8.7% in females, with an inverse-probability weighted odds ratio of 3.44 (95% CI 1.70-6.95) for males versus females. Among 60,605 able-bodied individuals, the prevalence of self-reported heart disease was 5.8% in males and 4.0% in females, with an inverse probability weighted odds ratio of 1.62 (95% CI 1.50-1.75) for males versus females. The effect of male sex on increasing heart disease prevalence was about two times higher among individuals with spinal cord injury than able-bodied individuals (relative difference in inverse probability weighted odds ratios = 2.12, 95% CI 1.08-4.51)., Conclusion: Males with spinal cord injury exhibit a significantly higher prevalence of heart disease, compared with females with spinal cord injury. Moreover, relative to able-bodied individuals, spinal cord injury amplifies sex-related differences in heart disease. Overall, this work will inform targeted cardiovascular prevention strategies, and may also inform a better understanding of cardiovascular disease progression in both able-bodied and individuals with spinal cord injury.

Objectives: In patients with stable ischemic heart disease, there is no evidence for the effect of revascularization treatment timing on the need for repeat procedures. We aimed to determine if repeat revascularizations differed among patients who received coronary artery bypass graft surgery after the time recommended by physicians compared with those who had timely percutaneous coronary intervention., Methods: We identified 25,520 British Columbia residents 60 years or older who underwent first-time nonemergency revascularization for angiographically proven, stable left main or multivessel ischemic heart disease between January 1, 2001, and December 31, 2016. We estimated unadjusted and adjusted cumulative incidence functions for repeat revascularization, in the presence of death as a competing risk, after index revascularization or last staged percutaneous coronary intervention for patients undergoing delayed coronary artery bypass grafting compared with timely percutaneous coronary intervention., Results: After adjustment with inverse probability of treatment weights, at 3 years, patients who underwent delayed coronary artery bypass grafting had a statistically significant lower cumulative incidence of a repeat revascularization compared with patients who received timely percutaneous coronary intervention (4.84% delayed coronary artery bypass grafting, 12.32% timely percutaneous coronary intervention; subdistribution hazard ratio, 0.16, 95% CI, 0.04-0.65)., Conclusions: Patients who undergo delayed coronary artery bypass grafting have a lower cumulative incidence of repeat revascularization than patients who undergo timely percutaneous coronary intervention. Patients who want to wait to receive coronary artery bypass grafting will see the benefit of lower repeat revascularization over percutaneous coronary intervention unaffected by a delay in treatment., Competing Interests: The authors reported no conflicts of interest. All other authors reported no conflicts of interest. The Journal policy requires editors and reviewers to disclose conflicts of interest and to decline handling or reviewing manuscripts for which they may have a conflict of interest. The editors and reviewers of this article have no conflicts of interest., (© 2024 The Author(s).)

Background: The advantage of coronary artery bypass grafting (CABG) over percutaneous coronary intervention (PCI), established in trials, may not be generalizable to populations in which the method of treatment determines the time to treatment. We sought to describe the methodology of a population-based observational study for assessing how changes in time to treatment may affect the comparative effectiveness of these 2 methods of coronary revascularization., Methods: We propose a framework of causal mediation analysis to compare the outcomes of choosing CABG over PCI, if patients selected for either method waited the same amount of time had they undergone a PCI. We will include patients who underwent a first-time, nonurgent isolated CABG or single-session PCI for multivessel or left main coronary artery disease from January 2001 to December 2016, in British Columbia. We will use absolute risk difference as a measure of the total effect of choosing CABG over PCI and partition it into the direct effect of the treatment choice and the effect mediated by the treatment-specific timing., Interpretation: Understanding how time to treatment mediates the relation between method of revascularization and outcomes will have implications for treatment selection, resource allocation and planning benchmarks. Findings on the benefits and risks of performing PCI or CABG within a certain time will guide multidisciplinary teams in determining the appropriate revascularization method for individual patients., Competing Interests: Competing interests: None declared., (© 2022 CMA Impact Inc. or its licensors.)

Purpose: In drug safety and effectiveness studies based on secondary data, the choice of an appropriate exposure measure for a given outcome can be challenging. Different measures of exposure can yield different estimates of treatment effect and safety. There is a knowledge gap with respect to developing and refining measures of drug exposure, to ensure that the exposure measure addresses the study question and is suitable for statistical analysis., Methods: We present a transparent, step-by-step approach to the development of drug exposure measures involving secondary data. This approach would be of interest to students and investigators with initial training in pharmacoepidemiology. We illustrate the approach using a study about Parkinson's disease., Results: We described the exposure specifications according to the study question. Next, we refined the exposure measure by linking it to knowledge about four major concepts in drug safety and effectiveness studies: drug use patterns, duration, timing, and dose. We then used this knowledge to guide the ultimate choice of exposure measure: time-varying, cumulative 6-month exposure to tamsulosin (a drug used to treat prostate hyperplasia)., Conclusions: The proposed approach links exposure specifications to four major concepts in drug safety and effectiveness studies. Formulating subject-matter knowledge about these major concepts provides an avenue to develop the rationale and specifications for the exposure measure., (© 2021 John Wiley & Sons Ltd.)

Background: Competing demands for operative resources may affect time to hip fracture surgery. We sought to determine the time to hip fracture surgery by variation in demand in Canadian hospitals., Methods: We obtained discharge abstracts of 151,952 patients aged 65 years or older who underwent surgery for a hip fracture between January, 2004 and December, 2012 in nine Canadian provinces. We compared median time to surgery (in days) when demand could be met within a two-day benchmark and when demand required more days, i.e. clearance time, to provide surgery, overall and stratified by presence of medical reasons for delay., Results: For persons admitted when demand corresponded to a 2-day clearance time, 68% of patients underwent surgery within the 2-day benchmark. When demand corresponded to a clearance time of one week, 51% of patients underwent surgery within 2 days. Compared to demand that could be served within the two-day benchmark, adjusted median time to surgery was 5.1% (95% confidence interval [CI] 4.1-6.1), 12.2% (95% CI 10.3-14.2), and 22.0% (95% CI 17.7-26.2) longer, when demand required 4, 6, and 7 or more days to clear the backlog, respectively. After adjustment, delays in median time to surgery were similar for those with and without medical reasons for delay., Conclusion: Increases in demand for operative resources were associated with dose-response increases in the time needed for half of hip fracture patients to undergo surgery. Such delays may be mitigated through better anticipation of day-to-day supply and demand and increased response capability.

Objectives: To describe an approach using concomitant medication log records for the construction of treatment episodes. Concomitant medication log records are routinely collected in clinical studies. Unlike prescription and dispensing records, concomitant medication logs collect utilisation data. Logs can provide information about drug safety and drug repurposing., Design: A prospective multicentre, multicohort observational study., Setting: Twenty-one clinical sites in the USA, Europe, Israel and Australia., Participants: 415 subjects from the de novo cohort of the Parkinson's Progression Markers Initiative., Methods: We construct treatment episodes of concomitant medication use. The proposed approach treats temporal gaps as a stoppage of medication and temporal overlaps as simultaneous use or changes in dose. Log records with no temporal gaps were combined into a single treatment episode., Results: 5723 concomitant medication log records were used to construct 3655 treatment episodes for 65 medications. There were 405 temporal gaps representing a stoppage of medication; 985 temporal overlaps representing simultaneous regimens of the same medication and 2696 temporal overlaps representing a change in dose regimen. The median episode duration was 37 months (IQ interval: 11-73 months)., Conclusions: The proposed approach for constructing treatment episodes offers a method of estimating duration and dose of treatment from concomitant medication log records. The accompanying recommendations guide log data collection to improve their quality for drug safety and drug repurposing., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Objective: We describe steps to operationalise a published conceptual framework for a contiguous hospitalisation episode using acute care hospital discharge abstracts. We then quantified the degree of bias induced by a first abstract episode, which does not account for hospital transfers., Design: Retrospective observational study., Setting: All acute care hospitals in nine Canadian provinces., Participants: We retrieved acute hospitalisation discharge abstracts for 189 448 patients aged 65 years and older admitted to acute care with hip fracture between 2003 and 2013., Primary and Secondary Outcome Measures: The percentage of patients treated surgically, delayed to surgery (defined as two or more days after admission) and dying, between contiguous hospitalisation episodes and the first abstract episodes of care., Results: Using contiguous hospitalisation episodes, 91.6% underwent surgery, 35.7% were delayed two or more days after admission and 6.7% died postoperatively, whereas, using the first abstract only, these percentages were 83.7%, 32.5% and 6.5%, respectively., Conclusion: We demonstrate that not accounting for hospital transfers when evaluating the association between surgical timing and death underestimates reporting of the percentage of patients treated surgically and delayed to surgery by 9%, and the percentage who die after surgery by 3%. Researchers must be aware of this potential and avoidable bias as, depending on the purpose of the study, erroneous inferences may be drawn., Competing Interests: Competing interests: The authors declare that (1) Boris Sobolev, Pierre Guy and the Collaborative have received grants from the Canadian Institutes of Health Research related to this work. (2) Pierre Guy also receives funding from the Natural Sciences and Engineering Research Council of Canada, the Canadian Foundation for Innovation and the British Columbia Specialists Services Committee for work around hip fracture care not related to this manuscript. He has also received fees from the BC Specialists Services Committee (for a provincial quality improvement project on redesign of hip fracture care) and from Stryker Orthopedics (as a product development consultant). He is a board member and shareholder in Traumis Surgical Systems Inc. and a board member for the Canadian Orthopedic Foundation. He also serves on the speakers’ bureaus of AO Trauma North America and Stryker Canada. (3) Suzanne Morin reports research grants from Amgen Canada, and from Merck, personal fees from Amgen Canada outside the submitted work., (© Author(s) (or their employer(s)) 2018. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: The appropriate timing of hip fracture surgery remains a matter of debate. We sought to estimate the effect of changes in timing policy and the proportion of deaths attributable to surgical delay., Methods: We obtained discharge abstracts from the Canadian Institute for Health Information for hip fracture surgery in Canada (excluding Quebec) between 2004 and 2012. We estimated the expected population-average risks of inpatient death within 30 days if patients were surgically treated on day of admission, inpatient day 2, day 3 or after day 3. We weighted observations with the inverse propensity score of surgical timing according to confounders selected from a causal diagram., Results: Of 139 119 medically stable patients with hip fracture who were aged 65 years or older, 32 120 (23.1%) underwent surgery on admission day, 60 505 (43.5%) on inpatient day 2, 29 236 (21.0%) on day 3 and 17 258 (12.4%) after day 3. Cumulative 30-day in-hospital mortality was 4.9% among patients who were surgically treated on admission day, increasing to 6.9% for surgery done after day 3. We projected an additional 10.9 (95% confidence interval [CI] 6.8 to 15.1) deaths per 1000 surgeries if all surgeries were done after inpatient day 3 instead of admission day. The attributable proportion of deaths for delays beyond inpatient day 2 was 16.5% (95% CI 12.0% to 21.0%)., Interpretation: Surgery on admission day or the following day was estimated to reduce postoperative mortality among medically stable patients with hip fracture. Hospitals should expedite operating room access for patients whose surgery has already been delayed for nonmedical reasons., Competing Interests: Competing interests: Boris Sobolev, Pierre Guy and the Collaborative report receiving grants from the Canadian Institutes of Health Research related to this work. Pierre Guy reports receiving grants from the Natural Sciences and Engineering Research Council of Canada, the Canadian Foundation for Innovation and the British Columbia Specialists Services Committee for work regarding hip fracture care, outside the submitted work. He has also received fees from the BC Specialists Services Committee (for a provincial quality improvement project on redesign of hip fracture care) and from Stryker Orthopaedics (as a product development consultant), outside the submitted work. He is a board member and shareholder in Traumis Surgical Systems Inc. and a board member for the Canadian Orthopaedic Foundation. He also serves on the speakers’ bureaus of AOTrauma North America and Stryker Canada. Suzanne Morin reports research grants from Amgen Canada, outside the submitted work. Jason Kim and Lisa Kuramoto report receiving grants from the Canadian Institutes of Health Research, during the conduct of the study. No other competing interests were declared., (© 2018 Joule Inc. or its licensors.)

Purpose: Failure to account for medically necessary delays may lead to an underestimation of early surgery benefits. This study investigated the feasibility of using administrative data to identify the National Institute for Health and Care Excellence (NICE) 124 guideline list of conditions that appropriately delay hip fracture surgery., Methods: We assembled a list of diagnosis and procedure codes to reflect the NICE 124 conditions. The list was reviewed and updated by an advanced clinical coder. The list was refined by five clinical experts. We then screened Canadian Institute for Health Information discharge abstracts for 153 918 patients surgically treated for a non-pathological first hip fracture between 1 January 2004 and 31 December 2012 for diagnosis codes present on admission and procedure codes that antedated hip fracture surgery. We classified abstracts as having medical reasons for delaying surgery based on the presence of these codes., Results: In total, 10 237 (6.7%; 95% CI 6.5% to 6.8%) patients had diagnostic and procedure codes indicating medical reasons for delay. The most common reasons for medical delay were exacerbation of a chronic chest condition (35.9%) and acute chest infection (23.2%). The proportion of patients with reasons for medical delays increased with time from admission to surgery: 3.9% (95% CI 3.6% to 4.1%) for same day surgery; 4.7% (95% CI 4.5% to 4.8%) for surgery 1 day after admission; 7.1% (95% CI 6.9% to 7.4%) for surgery 2 days after admission; and 15.5% (95% CI 15.1% to 16.0%) for surgery more than 2 days after admission. The trend was seen for admissions on weekday working hours, weekday after hours and on weekends., Conclusion: Administrative data can be considered to identify conditions that appropriately delay hip fracture surgery. Accounting for medically necessary delays can improve estimates of the effectiveness of early surgery., Competing Interests: Competing interests: The authors declare the following. (1) BS, PG and the Collaborative have received grants from the Canadian Institutes of Health Research related to this work. (2) PG also receives funding from the Natural Sciences and Engineering Research Council of Canada, the Canadian Foundation for Innovation and the British Columbia Specialists Services Committee for work around hip fracture care not related to this manuscript. He has also received fees from the BC Specialists Services Committee (for a provincial quality improvement project on redesign of hip fracture care) and from Stryker Orthopedics (as a product development consultant). He is a board member and shareholder in Traumis Surgical Systems Inc. and a board member for the Canadian Orthopedic Foundation. He also serves on the speakers’ bureaus of AO Trauma North America and Stryker Canada. (3) SM reports research grants from Amgen Canada and from Merck, personal fees from Amgen Canada outside the submitted work., (© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)

Purpose: There is limited information in administrative databases on the occurrence of serious but treatable complications after hip fracture surgery. This study sought to determine the feasibility of identifying the occurrence of serious but treatable complications after hip fracture surgery from discharge abstracts by applying the Agency for Healthcare Research and Quality (AHRQ) Patient Safety Indicator 4 (PSI-4) case-finding tool., Methods: We obtained Canadian Institute for Health Information discharge abstracts for patients 65 years or older, who were surgically treated for non-pathological first hip fracture between 1 January 2004 and 31 December 2012 in Canada, except for Quebec. We applied specifications of AHRQ Patient Safety Indicators 04, Version 5.0 to identify complications from hip fracture discharge abstracts., Results: Out of 153 613 patients admitted with hip fracture, we identified 12 383 (8.1%) patients with at least one postsurgical complication. From patients with postsurgical complications, we identified 3066 (24.8%) patient admissions to intensive care unit. Overall, 7487 (4.9%) patients developed pneumonia, 1664 (1.1%) developed shock/myocardial infarction, 651 (0.4%) developed sepsis, 1862 (1.1%) developed deep venous thrombosis/pulmonary embolism and 1919 (1.3%) developed gastrointestinal haemorrhage/acute ulcer., Conclusions: We report that 8.1% of patients developed at least one inhospital complication after hip fracture surgery in Canada between 2004 and 2012. The AHRQ PSI-4 case-finding tool can be considered to identify these serious complications for evaluation of postsurgical care after hip fracture., Competing Interests: Competing interests: The authors declare that (1) BS, PG and the Collaborative have received grants from the Canadian Institutes of Health Research related to this work. (2) PG also receives funding from the Natural Sciences and Engineering Research Council of Canada, the Canadian Foundation for Innovation and the British Columbia Specialists Services Committee for work around hip fracture care not related to this manuscript. He has also received fees from the BC Specialists Services Committee (for a provincial quality improvement project on redesign of hip fracture care) and from Stryker Orthopedics (as a product development consultant). He is a board member and shareholder in Traumis Surgical Systems Inc. and a board member for the Canadian Orthopedic Foundation. He also serves on the speakers’ bureaus of AO Trauma North America and Stryker Canada. (3)SNM reports research grants from Amgen Canada, and from Merck, personal fees from Amgen Canada outside the submitted work. (4) KJS is a postdoctoral fellow whose salary is paid by Canadian Institutes of Health Research funding related to this work., (© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)

Background: Second hip fractures account for up to 15% of all hip fractures. We sought to determine if the proportion of hip fracture surgeries for second hip fracture changed over time in terms of patient and fracture characteristics., Methods: We reviewed the records of patients older than 60 years hospitalized for hip fracture surgery between 1990 and 2005 in British Columbia. We studied the proportion of surgeries for second hip fracture among all hip fracture surgeries. Linear regression tested for trends across fiscal years for women and men., Results: We obtained 46 341 patient records. Second hip fracture accounted for 8.3% of hip fracture surgeries. For women the proportion of second hip fracture surgeries increased linearly from 4% to 13% with each age decade ( p = 0.001) and across fiscal years ( p = 0.002). In men the proportion of second hip fracture surgeries was 5% for each age decade between the ages of 60 and 90 years across fiscal years, increasing to 8% for men older than 90 years across fiscal years ( p = 0.20). These sex-specific trends were similar for both pertrochanteric and transcervical fracture types., Conclusion: Second hip fracture surgeries account for an increasing proportion of hip fracture surgeries and may require more health care resources to minimize poorer reported outcomes. Future research should determine whether more health care resources are required to manage these patients and optimize their outcomes.

Two hypotheses were offered for the effect of shorter hospital stays on mortality after hip fracture surgery: worsening the quality of care and shifting death occurrence to postacute settings.We tested whether the risk of hospital death after hip fracture surgery differed across years when postoperative stays shortened, and whether care factors moderated the association.Analysis of acute hospital discharge abstracts for subgroups defined by hospital type, bed capacity, surgical volume, and admission time.153,917 patients 65 years or older surgically treated for first hip fracture.Risk of hospital death.We found a decrease in the 30-day risk of hospital death from 7.0% (95%CI: 6.6-7.5) in 2004 to 5.4% (95%CI: 5.0-5.7) in 2012, with an adjusted odds ratio [OR] 0.71 (95%CI: 0.63-0.80). In subgroup analysis, only large community hospitals showed the reduction of ORs by calendar year. No trend was observed in teaching and medium community hospitals. By 2012, the risk of death in large higher volume community hospitals was 34% lower for weekend admissions, OR = 0.66 (95%CI: 0.46-0.95) and 39% lower for weekday admissions, OR = 0.61 (95%CI: 0.40-0.91), compared to 2004. In large lower volume community hospitals, the 2012 risk was 56% lower for weekend admissions, OR = 0.44 (95%CI: 0.26-0.75), compared to 2004.The risk of hospital death after hip fracture surgery decreased only in large community hospitals, despite universal shortening of hospital stays. This supports the concern of worsening the quality of hip fracture care due to shorter stays.

Background: Where patients with hip fracture undergo treatment may influence their outcome. We compared the risk of in-hospital death after hip fracture by treatment setting in Canada., Methods: We examined all discharge abstracts from the Canadian Institute for Health Information with diagnosis codes for hip fracture involving patients 65 years and older who were admitted to hospital with a nonpathological first hip fracture between Jan. 1, 2004, and Dec. 31, 2012, in Canada (excluding Quebec). We compared the risk of in-hospital death, overall and after surgery, between teaching hospitals and community hospitals of various bed capacities, accounting for variation in length of stay., Results: Compared with the number of deaths per 1000 admissions at teaching hospitals, there were an additional 3 (95% confidence interval [CI] 1-6), 14 (95% CI 10-18) and 43 (95% CI 35-51) deaths per 1000 admissions at large, medium and small community hospitals, respectively. For the risk of in-hospital death overall, the adjusted odds ratios (ORs) were 1.05 (95% CI 0.99-1.11), 1.16 (95% CI 1.09-1.24) and 1.44 (95% CI 1.31-1.57) at large, medium and small community hospitals, respectively, compared with teaching hospitals. For the risk of postsurgical death in hospital, the adjusted ORs were 1.06 (95% CI 1.00-1.13), 1.13 (95% CI 1.04-1.23) and 1.18 (95% CI 0.87-1.60) at large, medium and small community hospitals, respectively., Interpretation: Compared with teaching hospitals, the risk of in-hospital death among patients with hip fracture was higher at medium and small community hospitals, and the risk of in-hospital death after surgery was higher at medium community hospitals. No differences were found between teaching and large community hospitals. Future research should examine the role of volume, demand and bed occupancy for observed differences., (© 2016 Canadian Medical Association or its licensors.)

Episodes of care defined by the event of hip fracture surgery are widely used for the assessment of surgical wait times and outcomes. However, this approach does not consider nonoperative deaths, implying that survival time begins at the time of procedure. This approach makes treatment effect implicitly conditional on surviving to treatment. The purpose of this article is to describe a novel conceptual framework for constructing an episode of hip fracture care to fully evaluate the incidence of adverse events related to time after admission for hip fracture. This admission-based approach enables the assessment of the full harm of delay by including deaths while waiting for surgery, not just deaths after surgery. Some patients wait until their conditions are optimized for surgery, whereas others have to wait until surgical service becomes available. We provide definitions, linkage rules, and algorithms to capture all hip fracture patients and events other than surgery. Finally, we discuss data elements for stratifying patients according to administrative factors for delay to allow researchers and policymakers to determine who will benefit most from expedited access to surgery., (© 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.)

Unlabelled: Changes in bed management and access policy aimed to shorten Canadian hip fracture hospital stay. Secular trends in hip fracture total, preoperative, and postoperative stay are unknown. Hip fracture stay shortened from 2004 to 2012, mostly from shortening postoperative stay. This may reflect changes in bed management rather than access policy., Purpose: To compare the probability of discharge by time after patient admission to hospital with first-time hip fracture over a period of nine calendar years., Methods: We retrieved acute hospitalization records for 169,595 patients 65 years and older, who were admitted to an acute care hospital with hip fracture between 2004 and 2012 in Canada (outside of Quebec). The main outcome measure was cumulative incidence of discharge by inpatient day, accounting for competing events that end hospital stay., Results: The probability of surgical discharge within 30 days of admission increased from 57.2 % in 2004 to 67.3 % in 2012. The probability of undergoing surgery on day of admission or day after fluctuated around 58.5 % over the study period. For postoperative stay, the discharge probability increased from 6.8 to 12.2 % at day 4 after surgery and from 57.2 to 66.6 % at day 21 after surgery, between 2004 and 2012. The differences across years persisted after adjustment for characteristics of patients, fracture, comorbidity, treatment, type and timing of surgery, and access to care., Conclusions: Hospital stay following hip fracture shortened substantially between 2004 and 2012 in Canada, mostly due to shortening of postoperative stays. Shorter hospital stays may reflect changes in bed management protocols rather than in access policy.

RÉSUMÉ La législation, dans de nombreuses juridictions, nécessite les établissements des soins de longue durée (SLD) d'avoir une infirmière en service 24 heures par jour, 7 jours par semaine. Bien que la recherche considérable existe sur l'intensité SLD de la dotation en personnel infirmier, il n'existe pas de la recherche empirique relative à cette exigence. Notre étude rétrospectif d'observation a comparé des installations en Saskatchewan avec 24/7 RN couverture aux établissements offrant moins de couverture, complétées par divers modèles de dotation des postes de nuit. Les ratios de risque associés à moins de 24/7 couverture RN complété de la dotation infirmière autorisé de nuit, ajusté pour l'intensité de dotation en personnel infirmier et d'autres facteurs de confusion potentiels, étaient de 1,17, IC 95% [0,91, 1,50] et 1.00, IC à 95% [0,72, 1,39], et avec moins de couverture 24/7 RN complété avec soin par aides personnels de nuit, les ratios de risque étaient de 1,46, IC 95% [1,11, 1,91] et 1,11, IC 95% [0,78, 1,58], pour les patients hospitalisés et de visites aux services d'urgence, respectivement. Ces résultats suggèrent que l'utilisation des soins de courte durée peut être influencée négativement par l'absence de la couverture 24/7 RN.

Background: Secondary prevention often targets women who suffer from higher rates of second hip fracture than men, especially in the early years after first fracture. Yet, the occurrence of second hip fracture by certain times also depends on the death rate, which is higher in men than women. We compared the risk of sustaining second hip fracture by a certain time between women and men remaining alive at that time., Methods: We retrieved 38,383 hospitalization records of patients aged 60 years or older, who were discharged alive after admission for hip fracture surgery between 1990 and 2005 in British Columbia, Canada. The outcome variable was the time to a subsequent hip fracture., Results: During ten years of follow-up, 2,902 (8%) patients sustained a second hip fracture, and 21,428 (56%) died before sustaining a second hip fracture. The risk of second hip fracture in the surviving post-fracture patients was higher in women than in men: 2% vs 2%, 5% vs 4%, 9% vs 7%, 15% vs 13%, and 35% vs 30% at 1, 2, 3, 5, and 10 years after initial trauma, respectively, crude OR=1.25 (95% CI: 1.13-1.39). However, the risk did not differ between women and men after adjustment, OR=1.09 (95% CI: 0.98-1.21)., Conclusions: The risk of second hip fracture persists for at least ten years among hip fracture survivors, and therefore secondary prevention should continue beyond an early post-fracture period. Women and men have similar risks of second hip fracture and both should be considered for secondary prevention., (Crown Copyright © 2015. Published by Elsevier Inc. All rights reserved.)

This study examined how nursing home facility ownership and organizational characteristics relate to emergency department (ED) transfer rates. The sample included a retrospective cohort of nursing home residents in the Vancouver Coastal Health region (n = 13,140). Rates of ED transfers were compared between nursing home ownership types. Administrative data were further linked to survey-derived data of facility organizational characteristics for exploratory analysis. Crude ED transfer rates (transfers/100 resident years) were 69, 70, and 51, respectively, in for-profit, non-profit, and publicly owned facilities. Controlling for sex and age, public ownership was associated with lower ED transfer rates compared to for-profit and non-profit ownership. Results showed that higher total direct-care nursing hours per resident day, and presence of allied health staff--disproportionately present in publicly owned facilities--were associated with lower transfer rates. A number of other facility organizational characteristics--unrelated to ownership--were also associated with transfer rates.

Background: Adverse drug events are a frequent cause of emergency department presentations. Administrative data could be used to identify patients presenting with adverse drug events for post-market surveillance, and to conduct research in patient safety and in drug safety and effectiveness. However, such data sources have not been evaluated for their completeness with regard to adverse drug event reporting. Our objective was to determine the proportion of adverse drug events to outpatient medications diagnosed at the point-of-care in emergency departments that were documented in administrative data., Methods: We linked the records of patients enrolled in a prospective observational cohort study on adverse drug events conducted in two Canadian tertiary care emergency departments to their administrative data. We compared the number of adverse drug events diagnosed and recorded at the point-of-care in the prospective study with the number of adverse drug events recorded in the administrative data., Results: Among 1574 emergency department visits, 221 were identified as adverse drug event-related in the prospective database. We found 15 adverse drug events documented in administrative records with ICD-10 codes clearly indicating an adverse drug event, indicating a sensitivity of 6.8% (95% CI 4.0-11.2%) of this code set. When the ICD-10 code categories were broadened to include codes indicating a very likely, likely or possible adverse event to a medication, 62 of 221 events were identifiable in administrative data, corresponding to a sensitivity of 28.1% (95% CI 22.3-34.6%)., Conclusions: Adverse drug events to outpatient medications were underreported in emergency department administrative data compared to the number of adverse drug events diagnosed and recorded at the point-of-care.

Background: To date, statistical methods that take into account fully the non-linear, longitudinal and multivariate aspects of clinical data have not been applied to the study of progression in Parkinson's disease (PD). In this paper, we demonstrate the usefulness of such methodology for studying the temporal and spatial aspects of the progression of PD. Extending this methodology further, we also explore the presymptomatic course of this disease., Methods: Longitudinal Positron Emission Tomography (PET) measurements were collected on 78 PD patients, from 4 subregions on each side of the brain, using 3 different radiotracers. Non-linear, multivariate, longitudinal random effects modelling was applied to analyze and interpret these data., Results: The data showed a non-linear decline in PET measurements, which we modelled successfully by an exponential function depending on two patient-related covariates duration since symptom onset and age at symptom onset. We found that the degree of damage was significantly greater in the posterior putamen than in the anterior putamen throughout the disease. We also found that over the course of the illness, the difference between the less affected and more affected sides of the brain decreased in the anterior putamen. Younger patients had significantly poorer measurements than older patients at the time of symptom onset suggesting more effective compensatory mechanisms delaying the onset of symptoms. Cautious extrapolation showed that disease onset had occurred some 8 to 17 years prior to symptom onset., Conclusions: Our model provides important biological insights into the pathogenesis of PD, as well as its preclinical aspects. Our methodology can be applied widely to study many other chronic progressive diseases.

Background: Our objective was to evaluate the effect of delays on adverse events while waiting for coronary artery bypass grafting (CABG)., Methods: An observational study that prospectively followed patients from registration on a wait list to removal for planned surgery, death while waiting, or unplanned emergency surgery. The population-based registry provided data on 12,030 patients with a record of registration on a wait list for first-time isolated CABG surgery between 1992 and 2005., Results: In total, 104 patients died and 382 patients underwent an emergency surgery before planned CABG. The death rate was 0.5 per 1000 patient-weeks in the semiurgent group and 0.6 per 1000 patient-weeks the nonurgent group, adjusted OR = 1.07 (95% confidence interval [CI] 0.69-1.65). The emergency surgery rate of 1.2 per 1000 patient-weeks in the nonurgent group was lower compared to 2.1 per 1000 patient-weeks in the semiurgent group (adjusted OR = 0.72, 95% CI 0.54-0.97). However, the nonurgent group had a greater cumulative incidence of preoperative death than the semiurgent group for almost all weeks on the wait list, adjusted OR = 1.92 (95% CI 1.25-2.95). The surgery rate was 1.2 per 1000 patient-weeks in the nonurgent group and 2.1 per 1000 patient-weeks in the semiurgent group, adjusted OR = 0.72 (95% CI 0.54-0.97). The cumulative incidence of emergency surgery before planned CABG was similar in the semiurgent and nonurgent groups, adjusted OR = 0.88, (95% CI 0.64-1.20)., Conclusion: Despite similar death rates in the semiurgent and nonurgent groups, the longer waiting times in the nonurgent group result in a greater cumulative incidence of death on the wait list compared to that in the semiurgent group. These longer waiting times also offset the lower rate of emergency surgery before planned admission in the nonurgent group so that the cumulative incidence of the emergency surgery was similar in both groups.

Background: Guided by the evidence that delaying coronary revascularization may lead to symptom worsening and poorer clinical outcomes, expansion in cardiac surgery capacity has been recommended in Canada. Provincial governments started providing one-time and recurring increases in budgets for additional open heart surgeries to reduce waiting times. We sought to determine whether the year of decision to proceed with non-emergency coronary bypass surgery had an effect on time to surgery., Methods: Using records from a population-based registry, we studied times between decision to operate and the procedure itself. We estimated changes in the length of time that patients had to wait for non-emergency operation over 14 calendar periods that included several years when supplementary funding was available. We studied waiting times separately for patients who access surgery through a wait list and through direct admission., Results: During two periods when supplementary funding was available, 1998-1999 and 2004-2005, the weekly rate of undergoing surgery from a wait list was, respectively, 50% and 90% higher than in 1996-1997, the period with the longest waiting times. We also observed a reduction in the difference between 90th and 50th percentiles of the waiting-time distributions. Forty percent of patients in the 1998, 1999, 2004 and 2005 cohorts (years when supplementary funding was provided) underwent surgery within 16 to 20 weeks following the median waiting time, while it took between 27 and 37 weeks for the cohorts registered in the years when supplementary funding was not available. Times between decision and surgery were shorter for direct admissions than for wait-listed patients. Among patients who were directly admitted to hospital, time between decision and surgery was longest in 1992-1993 and then has been steadily decreasing through the late nineties. The rate of surgery among these patients was the highest in 1998-1999, and has not changed afterwards, even for years when supplementary funding was provided., Conclusions: Waiting times for non-emergency coronary bypass surgery shortened after supplementary funding was granted to increase volume of cardiac surgical care in a health system with publicly-funded universal coverage for the procedure. The effect of the supplementary funding was not uniform for patients that access the services through wait lists and through direct admission.

Background: Guidelines for timing of elective bypass surgery were established by expert opinion; yet, there is little evidence to support the recommended target times., Objectives: To estimate the effect of timing of the procedure on in-hospital mortality by comparing groups of patients that differ in the duration of time between decision to operate and performed procedure., Research Design: We used a population-based registry to identify patients who underwent surgical coronary revascularization and their hospital discharge summaries to identify in-hospital death., Subjects: We studied 9593 patients who underwent surgical revascularization between 1992 and 2006 after registration on a wait list for first-time isolated coronary artery bypass grafting on an elective basis., Measures: The outcome was postoperative in-hospital death. The study variable was the timing of surgery, categorized as short, prolonged, and excessive delays according to the guidelines., Methods: The probability of in-hospital death in relation to timing of surgery was modeled by logistic regression that included a precalculated risk score for in-hospital death, with weighting observations by inverse propensity scores for the 3 surgery timing groups., Results: In-hospital death among patients with short delays was one third as likely as among those with excessive delays: adjusted odds ratio=0.32 (95% confidence interval 0.20-0.51). The protective effect was smaller and not significant for patients with prolonged delays; odds ratio=0.78 (95% confidence interval, 0.38-1.63)., Conclusions: Our findings suggest a survival benefit from performing elective surgical revascularization within the time frame recommended by the stricter of the 2 guidelines. Our results have implications for health systems that provide universal coverage and that budget the annual number of procedures.

Background: Asthma tends to be less well controlled among ethnic minority groups, and its prevalence in new immigrants increases significantly the longer they are in Canada; mainly due to their lack of familiarity with English and difficulty understanding information regarding the disease, health literacy, cultural issues, housing conditions, and lack of access to appropriate care services., Objective: To explore the effectiveness of different formats of culturally relevant information and its impact on asthma patients' self-management within the Punjabi, Mandarin, and Cantonese communities., Methods: Using a participatory approach, we developed and tested knowledge and community educational videos (with similar information, but used a different approach, i.e., scientific vs. colloquial) and a pictorial pamphlet. A total of 92 physician-diagnosed adult asthma patients (47 Chinese and 45 Punjabi) were assigned at random to three experimental groups (watched one or both videos) and one comparison group (read pictorial pamphlet) and participated in three in-person interviews and one telephone interview within a 9-month period. Patients received education on asthma self-management via videos and pamphlet and outcomes, including their knowledge of asthma triggers (environmental-related and behavioral-related triggers) and symptoms; inhaler use skills and patient-reported medication adherence were measured., Results: Knowledge of asthma symptoms, inhaler use, and understanding of physician's instructions improved significantly from pretest to 3 months post-intervention follow-up among all participants., Conclusions: Participants performed significantly better at follow-up than they did at baseline assessment, with the most notable improvements observed in the group that watched both community and knowledge videos. The results suggest that short, simple, culturally, and linguistically appropriate interventions can promote knowledge gain about asthma and improve inhaler use that can be sustained over the short term. Such interventions that provide authentic learning materials that draw on patients' life experiences and sociocultural context can overcome certain limitations of conventional patient education approaches.

Parkinson's disease is a relentlessly progressive neurodegenerative disease. Breakdown of compensatory mechanisms influencing putaminal dopamine processing could contribute to the progressive motor symptoms. We studied a cohort of 78 subjects (at baseline) with sporadic Parkinson's disease and 35 healthy controls with multi-tracer positron emission tomography scans to investigate the evolution of adaptive mechanisms influencing striatal dopamine processing in Parkinson's disease progression. Presynaptic dopaminergic integrity was assessed with three radioligands: (i) [(11)C](±)dihydrotetrabenazine, to estimate the density of vesicular monoamine transporter type 2; (ii) [(11)C]d-threo-methylphenidate, to label the dopamine transporter; and (iii) 6-[(18)F]fluoro-L-DOPA, to assess the activity of aromatic amino acid decarboxylase and storage of 6-[(18)F]-fluorodopamine in synaptic vesicles. The subjects with Parkinson's disease and the healthy controls underwent positron emission tomography scans at the initial visit and after 4 and 8 years of follow-up. Non-linear multivariate regression analyses with random effects were utilized to model the longitudinal changes in tracer values in the putamen standardized relative to normal controls. We found evidence for possible upregulation of dopamine synthesis and downregulation of dopamine transporter in the more severely affected putamen in the early stage of Parkinson's disease. The standardized 6-[(18)F]fluoro-L-DOPA and [(11)C]d-threo-methylphenidate values tended to approach [(11)C](±)dihydrotetrabenazine values in the putamen in later stages of disease (i.e. for [(11)C](±)dihydrotetrabenazine values <25% of normal), when the rates of decline in the positron emission tomography measurements were similar for all the markers. Our data suggest that compensatory mechanisms decline as Parkinson's disease progresses. This breakdown of compensatory strategies in the putamen could contribute to the progression of motor symptoms in advanced disease.

Study Objective: Our objectives are to describe the outcomes of patients presenting to the emergency department (ED) because of an adverse drug event and to compare them with outcomes of patients presenting for other reasons., Methods: This prospective observational study was conducted at Vancouver General Hospital, a 955-bed tertiary care hospital. We prospectively enrolled adults presenting to the ED between March and June 2006, using a systematic sampling algorithm. Pharmacists and physicians independently evaluated patients for adverse drug events. An independent committee reviewed and adjudicated cases in which assessments were discordant or uncertain. Data from the index visit were linked to vital statistics, administrative health services utilization, and cost of care data., Results: Of 1,000 patients, 122 (12.2%; 95% confidence interval [CI] 10.3% to 14.4%) presented to the ED because of an adverse drug event. Of these, 48 presented because of an adverse drug reaction (one type of adverse drug event defined as an unintended response that occurred despite use of an appropriate drug dosage). We found no difference in mortality among patients presenting with and without adverse drug reactions (14.6% versus 5.9%; hazard ratio 1.57; 95% CI 0.70 to 3.52). After adjustment, patients with adverse drug events had a higher risk of spending additional days in the hospital per month (6.3% versus 3.4%; odds ratio 1.52; 95% CI 1.43 to 1.62) and higher rate of outpatient health care encounters (1.73 versus 1.22; rate ratio 1.20; 95% CI 1.03 to 1.40). The adjusted median monthly cost of care was 1.90 times higher (Can $325 versus $96; 95% CI 1.18 to 3.08)., Conclusion: ED patients presenting with an adverse drug event incurred greater health services utilization and costs during a 6-month follow-up period compared with patients presenting for other reasons., (Copyright © 2011 American College of Emergency Physicians. Published by Mosby, Inc. All rights reserved.)

Objective: To investigate in vivo the impact of age on nigrostriatal dopamine dysfunction in Parkinson's disease (PD)., Methods: PD patients (n = 78) and healthy control subjects (n = 35) underwent longitudinal positron emission tomography assessments using 3 presynaptic dopamine markers: (1) [¹¹C](±)dihydrotetrabenazine (DTBZ), to estimate the density of the vesicular monoamine transporter type 2; (2) [¹¹C]d-threo-methylphenidate, to estimate the density of the plasma membrane dopamine transporter; and (3) 6-[¹⁸F]-fluoro-L-dopa, to estimate the activity of the enzyme dopa-decarboxylase., Results: The study comprised 438 PD scans and 241 control scans (679 scans in total). At symptom onset, the loss of putamen DTBZ binding was substantially greater in younger compared to older PD patients (p = 0.015). Remarkably, however, the rate of progression of DTBZ binding loss was significantly slower in younger patients (p < 0.05). The estimated presymptomatic phase of the disease spanned more than 2 decades in younger patients, compared to 1 decade in older patients., Interpretation: Our results suggest that, compared to older patients, younger PD patients progress more slowly and are able to endure more damage to the dopaminergic system before the first motor symptoms appear. These observations suggest that younger PD patients have more efficient compensatory mechanisms., (Copyright © 2011 American Neurological Association.)

Background: The prevalence of childhood obesity is increasing at an alarming rate. Many local governments have enacted policies to increase physical activity in schools as a way to combat childhood obesity. We conducted a systematic review and meta-analysis to determine the effect of school-based physical activity interventions on body mass index (BMI) in children., Methods: We searched MEDLINE, EMBASE, CINAHL and the Cochrane Central Register of Controlled Trials up to September 2008. We also hand-searched relevant journals and article reference lists. We included randomized controlled trials and controlled clinical trials that had objective data for BMI from before and after the intervention, that involved school-based physical activity interventions and that lasted for a minimum of 6 months., Results: Of 398 potentially relevant articles that we identified, 18 studies involving 18 141 children met the inclusion criteria. The participants were primarily elementary school children. The study duration ranged from 6 months to 3 years. In 15 of these 18 studies, there was some type of co-intervention. Meta-analysis showed that BMI did not improve with physical activity interventions (weighted mean difference -0.05 kg/m(2), 95% confidence interval -0.19 to 0.10). We found no consistent changes in other measures of body composition., Interpretation: School-based physical activity interventions did not improve BMI, although they had other beneficial health effects. Current population-based policies that mandate increased physical activity in schools are unlikely to have a significant effect on the increasing prevalence of childhood obesity.

Background: Many health care systems now use priority wait lists for scheduling elective coronary artery bypass grafting (CABG) surgery, but there have not yet been any direct estimates of reductions in in-hospital mortality rate afforded by ensuring that the operation is performed within recommended time periods., Methods: We used a population-based registry to identify patients with established coronary artery disease who underwent isolated CABG in British Columbia, Canada. We studied whether postoperative survival during hospital admission for CABG differed significantly among patients who waited for surgery longer than the recommended time, 6 weeks for patients needing semi-urgent surgery and 12 weeks for those needing non-urgent surgery., Results: Among 7316 patients who underwent CABG, 97 died during the same hospital admission, for a province-wide death rate at discharge of 1.3%. The observed proportion of patients who died during the same admission was 1.0% (27 deaths among 2675 patients) for patients treated within the recommended time and 1.5% (70 among 4641) for whom CABG was delayed. After adjustment for age, sex, anatomy, comorbidity, calendar period, hospital, and mode of admission, patients with early CABG were only 2/3 as likely as those for whom CABG was delayed to experience in-hospital death (odds ratio 0.61; 95% confidence interval [CI] 0.39 to 0.96). There was a linear trend of 5% increase in the odds of in-hospital death for every additional month of delay before surgery, adjusted OR = 1.05 (95% CI 1.00 to 1.11)., Conclusion: We found a significant survival benefit from performing surgical revascularization within the time deemed acceptable to consultant surgeons for patients requiring the treatment on a semi-urgent or non-urgent basis.

Background: Currently there are no direct estimates of mortality reduction afforded by coronary-artery bypass grafting (CABG) that take into account the deaths among patients for whom coronary revascularization was indicated but who did not undergo the treatment. The objective of this analysis was to compare survival after the treatment decision between patients who underwent CABG and those who remained untreated., Methods: We used a population-based registry to identify patients with established coronary artery disease who were to undergo first-time isolated CABG. We measured the effect of surgical revascularization on survival after the treatment decision in two cohorts of patients categorized by symptoms, coronary anatomy, and left ventricular function., Results: One in 10 patients died during the five years after treatment decision. The hazard of death among patients who underwent CABG was 51 percent of that for the untreated group, the adjusted hazard ratio was 0.51 (95 percent confidence interval, 0.43 to 0.61). The effect was stronger when CABG was performed within the recommended time: adjusted hazard ratios were 0.43 (95 percent confidence interval, 0.35 to 0.53) and 0.58 (95 percent confidence interval, 0.48 to 0.70) for early and late intervention, respectively; chi-square for the difference between hazard ratios was 12.2 (P < 0.001)., Conclusion: Estimates that account for patients who died before they could undergo a required CABG indicate a significant survival benefit of performing early surgical revascularization even for patients registered to undergo the operation on the non-urgent basis.

Background: Evidence-based medicine has been advanced by the use of standards for reporting the design and methodology of randomized controlled trials (RCT). Indeed, without this information it is difficult to assess the quality of evidence from an RCT. Although a variety of statistical methods are available for the analysis of recurrent events, reporting the effect of an intervention on outcomes that recur is an area that remains poorly understood in clinical research. The purpose of this paper is to outline guidelines for reporting results from RCTs where the outcome of interest is a recurrent event., Methods: We used a simulation study to relate an event process and results from analyses of the gamma-Poisson, independent-increment, conditional, and marginal Cox models. We reviewed the utility of regression models for the rate of a recurrent event by articulating the associated study questions, preenting the risk sets, and interpreting the regression coefficients., Results: Based on a single data set produced by simulation, we reported and contrasted results from statistical methods for evaluating treatment effect from an RCT with a recurrent outcome. We showed that each model has different study questions, assumptions, risk sets, and rate ratio interpretation, and so inferences should consider the appropriateness of the model for the RCT., Conclusion: Our guidelines for reporting results from an RCT involving a recurrent event suggest that the study question and the objectives of the trial, such as assessing comparable groups and estimating effect size, should determine the statistical methods. The guidelines should allow clinical researchers to report appropriate measures from an RCT for understanding the effect of intervention on the occurrence of a recurrent event.

Objective: This study compared two methods of booking elective surgery - booking from wait lists and pre-booking surgery dates at the time of decision to operate - in terms of cancellations of elective procedures and time to surgery., Methods: The authors conducted simulation experiments with group randomized design, in which the unit of allocation was the hospital and the units of analysis were both the hospital and the patient., Results: In the case of pre-booking, cancellation of high-priority elective procedures was only one-third as likely as it was in the case of booking from wait lists (odds ratio 0.35; 95% confidence interval 0.18-0.68). After adjustment for hospital and patient factors, the weekly likelihood that patients on the wait list had their operation was about 20% higher for medium-priority procedures (OR 1.21; CI 1.18-1.24) after pre-booking surgery dates., Conclusion: The findings suggest that redesigning booking processes may improve the performance of surgical services., (Copyright © 2008 Longwoods Publishing.)

Background: Studies have shown patients who are delayed for surgical cardiac revascularization are faced with increased risks of symptom deterioration and death. This could explain the observation that operative mortality among persons undergoing coronary artery bypass surgery (CABG) is higher among women than men. However, in jurisdictions that employ priority wait lists to manage access to elective cardiac surgery, there is little information on whether women wait longer than men for CABG. It is therefore difficult to ascertain whether higher operative mortality among women is due to biological differences or to delayed access to elective CABG., Methods: Using records from a population-based registry, we compared the wait-list time between women and men in British Columbia (BC) between 1990 and 2000. We compared the number of weeks from registration to surgery for equal proportions of women and men, after adjusting for priority, comorbidity and age., Results: In BC in the 1990 s, 9,167 patients aged 40 years and over were registered on wait lists for CABG and spent a total of 136,071 person-weeks waiting. At the time of registration for CABG, women were more likely to have a comorbid condition than men. We found little evidence to suggest that women waited longer than men for CABG after registration, after adjusting for comorbidity and age, either overall or within three priority groups., Conclusion: Our findings support the hypothesis that higher operative mortality during elective CABG operations observed among women is not due to longer delays for the procedure.

Background: There is increasing interest in health care resource use (HRU) in Canada, particularly in resources associated with acute exacerbations of chronic obstructive pulmonary disease (COPD)., Objective: To identify HRU due to exacerbations of COPD., Methods: A 52-week, multicentre, prospective, observational study of HRU due to exacerbations in patients with moderate to severe COPD was performed. Patients were recruited from primary care physicians and respirologists in urban and rural centres in Canada., Results: In total, 524 subjects (59% men) completed the study. Their mean age was 68.2+/-9.4 years, with a forced expiratory volume in 1 s of 1.01+/-0.4 L. Patients had significant comorbidities. There were 691 acute exacerbations of COPD, which occurred in 53% of patients: 119 patients (23%) experienced one acute exacerbation, 70 patients (13%) had two acute exacerbations and 89 patients (17%) had three or more acute exacerbations. Seventy-five patients were admitted to hospital, with an average length of stay of 13.2 days. Fourteen of the patients spent time in an intensive care unit (average length of stay 5.6 days). Factors associated with acute exacerbations of COPD included lower forced expiratory volume in 1 s (P<0.001), high number of respiratory medications prescribed (P=0.037), regular use of oral corticosteroids (OCSs) (P=0.008) and presence of depression (P<0.001). Of the 75 patients hospitalized, only 53 received OCSs, four received referral for rehabilitation and 15 were referred for home care., Conclusions: The present study showed a high prevalence of COPD exacerbations, which likely impacted on HRU. There was evidence of a lack of appropriate management of exacerbations, especially with respect to use of OCSs, and referral for pulmonary rehabilitation and home care.

Background: Falls are the most common cause of injury among elderly people; half of those people fall recurrently. The objective of these simulation studies was to describe the Mean Cumulative Function (MCF) and to evaluate the utility of the MCF in detecting differences between groups experiencing different patterns of event intensities., Methods: We specified 250 participants per group with a maximum follow-up time of 365 days. A participant could experience 0, 1, 2, 3, or 4 falls. In the baseline experiment, Groups A and B had an average intensity of 60 and 90 days to the first fall event. These event intensities remained constant for events 2-4. Group C represents a short term "strong" initial impact of the intervention modeled for falls 1 and 2, with an average intensity of one fall per 117 days; however, the intervention wanes to "moderate" for falls 3 and 4 with an average intensity of one fall per 90 days. Group D represents a long-term "strong" impact of the intervention modeled by an average intensity of one fall per 117 days for all subsequent events., Results: The MCF was able to detect differences between groups that had varying intensities of subsequent falls. In Group A, all participants experienced at least one fall, whereas Groups B, C, and D had 4, 9, and 15 participants, respectively, who did not experience any falls. The proportion of participants who had 4 falls declined from 84% to 40% in Groups A and D, respectively. When Group A was compared to Group D, the MCF difference detected the prevention of, on average, one fall per person within 175 days. Discussion. A novel instrument for this field of clinical research--the MCF--allows investigators to compare the average number of falls per participant when the intervention reduces the intensity of subsequent falls.

Purpose: Atherosclerosis contributes to cardiovascular mortality and morbidity even with aggressive lipid management. Our objective is to determine whether a combined pharmacological and lifestyle intervention can improve atherosclerosis., Methods: We conducted a 2-year observational study at a specialized clinic in a tertiary care hospital. One hundred fifty-six subjects with coronary disease were enrolled in an intensive pharmacological management and lifestyle measures (including counseling and exercise training) program designed to reach specific targets. The main outcome measures were carotid intima media thickness and plaque area; brachial artery flow-mediated dilation; nitroglycerin-mediated dilation; flow-mediated dilation-nitroglycerin-mediated dilation ratio; laboratory parameters including lipids, glucose, creatinine, and homocysteine; and physical fitness., Results: At completion, there were improvements in lipids and physical fitness. There were no overall changes in flow-mediated dilation, nitroglycerin-mediated dilation, or carotid intima media thickness in the entire cohort. However, multivariate logistic regression showed that dietary and exercise variables, such as increasing fiber intake and reducing body weight and body fat percentage, were independent predictors of improvements in endothelial function and carotid plaque burden., Conclusions: Even in the setting of intensive pharmacological therapy, lifestyle interventions, including exercise training and dietary changes, are important determinants of improved endothelial function and atherosclerosis.

Background: In deciding where to undergo coronary-artery bypass grafting, the length of surgical wait lists is often the only information available to cardiologists and their patients. Our objective was to compare the cumulative incidence for death on the wait list according to the length of wait lists at the time of registration for the operation., Methods: The study cohort included 8966 patients who registered to undergo isolated coronary-artery bypass grafting (82.4% men; 71.9% semi-urgent; 22.4% non-urgent). The patients were categorized according to wait-list clearance time at registration: either "1 month or less" or "more than 1 month". Cumulative incidence for wait-list death was compared between the groups, and the significance of difference was tested by means of regression models., Results: Urgent patients never registered on a wait list with a clearance time of more than 1 month. Semi-urgent patients registered on shorter wait lists more often than non-urgent patients (79.1% vs. 44.7%). In semi-urgent and non-urgent patients, the observed proportion of wait-list deaths by 52 weeks was lower in category "1 month or less" than in category "more than 1 month" (0.8% [49 deaths] vs. 1.6% [39 deaths], P < 0.005). After adjustment, the odds of death before surgery were 64% higher in patients on longer lists, odds ratio [OR] = 1.64 (95% confidence interval [CI] 1.02-2.63). The observed death rate was higher in category "more than 1 month" than in category "1 month or less", 0.79 (95%CI 0.54-1.04) vs. 0.58 (95% CI 0.42-0.74) per 1000 patient-weeks, the adjusted OR = 1.60 (95%CI 1.01-2.53). Longer wait times (log-rank test = 266.4, P < 0.001) and higher death rates contributed to a higher cumulative incidence for death on the wait list with a clearance time of more than 1 month., Conclusion: Long wait lists for coronary-artery bypass grafting are associated with increased probability that a patient dies before surgery. Physicians who advise patients where to undergo cardiac revascularization should consider the risk of pre-surgical death that is associated with the length of a surgical wait list.

Objective: To compare the cumulative incidence of emergency surgery between two groups of patients classified according to the length of wait lists at the time of their registration for coronary artery bypass grafting (CABG) and to test for significant differences in the risk of emergency surgery resulting from registration on a longer wait list., Methods: A prospective study of all adult British Columbia residents who registered to undergo isolated CABG. We compared the time-dependent cumulative incidence for undergoing planned surgery through unplanned emergency admission before or during a certain wait-list week between two categories of wait-list size. The list size was a simple count of patients with higher or equal urgency to undergo CABG who were on a wait list at the time of registration of a new patient., Results: Wait lists with one month or less of clearance time were observed in all urgent patients and were more prevalent in semi-urgent than non-urgent patients (79.1% vs 44.7%, respectively). The patients registered on a list with a clearance time of more than one month had a rate of unplanned emergency admission similar to those on a list with a clearance time of one month or less, OR = 1.07 (95% CI, 0.78-1.47) after adjustment for age, sex, comorbidity, calendar period, urgency and week on the list. During fifty-two weeks of the wait-list follow-up, an equal proportion of patients underwent unplanned emergency surgery after registration on lists in both clearance-time categories, OR = 1.03 (95% CI, 0.78-1.37) after adjustment. The number of patients who underwent CABG without having been registered on a wait list in the same hospital exerted no independent effect., Conclusions: The length of a wait list at registration had no effect on the probability that a semi-urgent or non-urgent patient would undergo CABG through unplanned emergency admission before or during a certain wait-list week.

Background: The detrimental effect of delaying surgical revascularization has been estimated in randomized trials and observational studies. It has been argued that the Kaplan-Meier method used in quantifying the hazard of delayed treatment is not appropriate for summarizing the probability of competing outcomes. Therefore, we sought to improve the estimates of the risk of death associated with delayed surgical treatment of coronary artery disease., Methods: Population-based prospective study of 8,325 patients registered to undergo first time isolated coronary artery bypass grafting (CABG) in any of the four tertiary hospitals that provide cardiac care to adult residents of British Columbia, Canada. The cumulative incidence of pre-operative death, the cumulative incidence of surgery, and the probability that a patient, who may die or undergo surgery, dies if not operated by certain times over the 52-week period after the decision for CABG were estimated. The risks were quantified separately in two groups: high-severity at presentation were patients with either persistent unstable angina or stable angina and extensive coronary artery disease, and low-severity at presentation were stable symptomatic patients with limited disease., Results: The median waiting time for surgery was 10 weeks (interquartile range [IQR] 15 weeks) in the high-severity group and 21 weeks (IQR 30 weeks) in the low-severity group. One percent of patients died before surgery: 54 in the high-severity and 26 in the low-severity group. For 58 (72.5%) patients, death was related to CVD (acute coronary syndrome, 33; chronic CVD, 16; other CVD, 4; and sudden deaths, 5). The overall death rate from all causes was 0.61 (95% CI 0.48-0.74) per 1,000 patient-weeks, varying from 0.62 (95% CI 0.45-0.78) in the high-severity group to 0.59 (95% CI 0.37-0.82) in the low-severity group. After adjustment for age, sex, and comorbidity, the all-cause death rate in the low-severity group was similar to the high-severity group (OR = 1.02, 95% CI 0.64-1.62). The conditional probability of death was greater in the high-severity group than in the low-severity group both for all-cause mortality (p = 0.002) and cardiovascular deaths (p <0.001)., Conclusion: The probability of death conditional on not having undergone a required CABG increases with time spent on wait lists.

Background: Priority wait lists are common for managing access to cardiac surgery in publicly funded health systems. We evaluated whether longer delays contribute to the probability of death before surgery among patients prioritized into the less urgent category., Methods: We studied records of 9233 patients registered for isolated coronary artery bypass graft (CABG) in British Columbia, Canada. The primary outcome was death before surgery. We estimated the probability that a patient, who could be removed from the list as a result of surgery, death, or other competing events, dies on or before a certain wait-list week., Results: Despite similar death rates in semiurgent and nonurgent groups, 0.63 (95% confidence interval, 0.46-0.80) versus 0.58 (0.36-0.80) per 1000 patient-weeks, nonurgent patients were remaining on the list longer, which contributed to higher cumulative incidence of all-cause death than in semiurgent group (adjusted odds ratio = 1.66; 1.03-2.68). By 52 weeks on the wait list, 0.9% (0.6-1.1) and 1.3% (0.8-1.8) of patients died in semiurgent and nonurgent groups, respectively (P < 0.01). Similar proportions of deaths related to cardiovascular disease estimated over wait-list time in both groups (P = 0.40) were the result of shorter delays in the semiurgent group despite a higher rate of death resulting from cardiovascular disease (0.50 [0.36-0.65] vs. 0.34 [0.17-0.51] per 1000 patient-weeks)., Conclusion: Queuing according to urgency of treatment contributed to a higher proportion of CABG candidates dying before surgery from all causes in the nonurgent compared with the semiurgent group despite similar weekly death rates observed in both groups. However, similar probabilities of death resulting from cardiovascular disease observed in both groups over wait-list time were the result of shorter delays in the semiurgent group despite a higher rate of cardiovascular death.

Objective: To determine whether the probability of undergoing coronary bypass surgery within a certain time was related to the number of patients on the wait list at registration for the operation in a publicly funded health system., Methods: A prospective cohort study comparing waiting times among patients registered on wait lists at the hospitals delivering adult cardiac surgery. For each calendar week, the list size, the number of new registrations, and the number of direct admissions immediately after angiography characterized the demand for surgery., Results: The length of delay in undergoing treatment was associated with list size at registration, with shorter times for shorter lists (log-rank test 1,198.3, p<.0001). When the list size at registration required clearance time over 1 week patients had 42 percent lower odds of undergoing surgery compared with lists with clearance time less than 1 week (odds ratio [OR] 0.58 percent, 95 percent, confidence interval [CI] 0.53-0.63), after adjustment for age, sex, comorbidity, period, and hospital. The weekly number of new registrations exceeding weekly service capacity had an independent effect toward longer service delays when the list size at registration required clearance time less than 1 week (OR 0.56 percent, 95 percent CI 0.45-0.71), but not for longer lists. Every time the operation was performed for a patient requiring surgery without registration on wait lists, the odds of surgery for listed patients were reduced by 6 percent (OR 0.94, CI 0.93-0.95)., Conclusion: For wait-listed patients, time to surgery depends on the list size at registration, the number of new registrations, as well as on the weekly number of patients who move immediately from angiography to coronary bypass surgery without being registered on a wait list. Hospital managers may use these findings to improve resource planning and to reduce uncertainty when providing advice on expected treatment delays.

How do we know that innovations in healthcare delivery would work? In this paper, we discuss the idea of applying the methodology of group-randomized intervention studies to evaluation of surgical care policies using data from simulation experiments. We argue that a new interdisciplinary framework, which links health services research, operations research, and computer sciences, is required. Specifically, the methodological rigor of evaluative studies should be applied to the analysis of simulation experiments. In turn, the evaluation of policy initiatives should include the simulation of health-system operations. We introduce the framework and study design to evaluate methods for improving the peri-operative process with the use of patient flow simulations.

Background: The proportion of patients who undergo surgery within a clinically safe time is an important performance indicator in health systems that use wait lists to manage access to care. However, little is known about chances of on-time surgery according to variations in existing demand. We sought to determine what proportion of patients have had late coronary bypass surgery after registration on wait lists of different size in a network of hospitals with uniform standards for timing of surgery., Methods: Using records from a population-based registry, we studied wait-list times prospectively collected in a cohort of patients registered on wait lists for coronary artery bypass grafting procedures. We compared the number of weeks from registration to surgery against target access times established for three urgency groups. The chances of undergoing surgery within target time have been evaluated in relation to wait-list size at registration and the number of surgeries performed without registration on a wait list., Results: In 1991-2001, two in three patients were at risk of late surgery when registered on wait lists for isolated coronary bypass procedures in British Columbia, Canada. Although urgent patients had never seen a wait list with clearance time exceeding one week, the odds of on-time surgery were reduced by 25%, odds ratio [OR] = 0.75 (95% confidence interval [CI] 0.65-0.87) for every additional operation performed without registration on a list. When the wait list at registration required a clearance time of over one month, semi-urgent patients had 51% lower odds of on-time surgery as compared to lists with clearance time less than one week, OR = 0.49 (95%CI 0.41-0.60), after adjustment for age, sex, comorbidity, calendar period, hospital and week on the list. In the non-urgent group, the odds were 69% lower, OR = 0.31 (95%CI 0.20-0.47). Every time an operation in the same hospital was performed without registration on a wait list, the odds of on-time surgery for listed patients were reduced by 7%, OR = 0.93 (95%CI 0.91-0.95) in the semi-urgent group, and by 10%, OR = 0.90 (95%CI 0.87-0.94), in the non-urgent group., Conclusion: Chances of late surgery increase with the wait-list size for semi-urgent and non-urgent patients needing coronary bypass surgery. The weekly number of patients who move immediately from angiography to the operation without registration on a wait list reduced chances of surgery within target time in all urgency groups of listed patients. When advising patients who will be placed on the wait list about the expected time to treatment, hospital managers should take into account the current list size as well as the weekly number of patients who require CABG immediately after undergoing coronary angiography.

Background: Primary total hip arthroplasty (THA) is an effective treatment for hip osteoarthritis, assessed by whatever distribution-based measures of responsiveness. Yet, the group level evaluation has provided very little evidence contributes to our understanding of the large variation of treatment outcome. The objective is to develop criteria that classify individual treatment health related quality of life (HRQOL) outcome after primary THA, adjusted by preoperative scores., Methods: We prospectively measured 147 patients' disease specific HRQOL on the date of consultation and 12 months post operation by Western Ontario McMaster Universities Osteoarthritis Index (WOMAC). Regression models were used to determine the "expected" outcome for a certain individual baseline score. The ceiling effect of WOMAC measurement is addressed by implementing a left-censoring method., Results: The classification criteria are chosen to be the lower boundary of the 95% confidence interval (CI) of the estimated median from the regression. The robustness of the classification criteria was demonstrated using the Monte-Carlo simulation., Conclusion: The classification criteria are robust and can be applied in general orthopaedic research when the sample size is reasonable large (over 500).

Background: Dopamine terminal loss in the putamen of patients with Parkinson disease (PD) shows a regional heterogeneity, reflecting selective vulnerability of degenerating neurons to mechanisms of cell death., Hypothesis: If the same pathogenic mechanisms are responsible for the onset and progression of PD, the regional selectivity of dopamine cell loss will be the same throughout the course of the disorder., Objective: To investigate the regional selectivity of dopamine terminal loss during the progression of PD., Participants: We studied 67 patients with PD and 20 healthy subjects using positron emission tomography with [(11)C](+/-)dihydrotetrabenazine (DTBZ)., Results: Regional values of DTBZ binding potential (calculated as maximum specific binding [B(max)] divided by the equilibrium dissociation constant K(d)) against disease duration in the putamen of PD patients were best described by a multivariate exponential model with distinct parallel asymptotic values that were significantly (P<.001) different across 4 regions of the putamen. The extent of loss of DTBZ binding potential with disease progression during the clinical stage of PD (early vs late PD) was similar between the anterior (-33%, using early PD as the baseline) and posterior (-29%) putamen. In contrast, the extent of loss of DTBZ binding potential in early PD, which reflects the cumulated loss of DTBZ binding potential from the onset of the disorder (in healthy subjects vs those with early PD), was significantly (P<.001) lower in the posterior (-58%, using healthy subjects as the baseline) than the anterior (-42%) putamen., Conclusion: To the extent that DTBZ positron emission tomography provides an accurate estimate of loss of dopamine neurons, our findings suggest that the mechanisms responsible for the progression of PD may not be the same as those responsible for its onset.