15 results on '"Elena Szefer"'
Search Results
2. A Bayesian group sparse multi-task regression model for imaging genetics.
- Author
-
Keelin Greenlaw, Elena Szefer, Jinko Graham, Mary Lesperance, and Farouk S. Nathoo
- Published
- 2017
- Full Text
- View/download PDF
3. A Population‐Based Approach to Reporting System–Level Performance Measures for Rheumatoid Arthritis Care
- Author
-
Elena Szefer, Cheryl Barnabe, Vivian P. Bykerk, Claire E.H. Barber, Deborah A. Marshall, Marinka Twilt, Diane Lacaille, Natalie J. Shiff, Dianne Mosher, Joanne Homik, J. Carter Thorne, Vandana Ahluwalia, and Susanne M. Benseler
- Subjects
Adult ,Male ,musculoskeletal diseases ,medicine.medical_specialty ,Time Factors ,Databases, Factual ,MEDLINE ,Total population ,Population based ,Time-to-Treatment ,Arthritis, Rheumatoid ,03 medical and health sciences ,0302 clinical medicine ,Rheumatology ,immune system diseases ,Internal medicine ,Dmard therapy ,Prevalence ,medicine ,Humans ,Practice Patterns, Physicians' ,skin and connective tissue diseases ,Referral and Consultation ,Aged ,Quality Indicators, Health Care ,030203 arthritis & rheumatology ,British Columbia ,business.industry ,Incidence ,Middle Aged ,medicine.disease ,Drug Utilization ,Median time ,Antirheumatic Agents ,Rheumatoid arthritis ,Cohort ,Female ,Rheumatologists ,business ,Reporting system - Abstract
OBJECTIVE To operationalize and report on nationally endorsed rheumatoid arthritis (RA) performance measures (PMs) using health administrative data for British Columbia (BC), Canada. METHODS All patients with RA in BC ages ≥18 years were identified between January 1, 1997 and December 31, 2009 using health administrative data and followed until December 2014. PMs tested include: the percentage of incident patients with ≥1 rheumatologist visit within 365 days; the percentage of prevalent patients with ≥1 rheumatologist visit per year; the percentage of prevalent patients dispensed disease-modifying antirheumatic drug (DMARD) therapy; and time from RA diagnosis to DMARD therapy. Measures were reported on patients seen by rheumatologists, and in the total population. RESULTS The cohort included 38,673 incident and 57,922 prevalent RA cases. The percentage of patients seen by a rheumatologist within 365 days increased over time (35% in 2000 to 65% in 2009), while the percentage of RA patients under the care of a rheumatologist seen yearly declined (79% in 2001 to 39% in 2014). The decline was due to decreasing visit rates with increasing follow-up time rather than calendar effect. The percentage of RA patients dispensed a DMARD was suboptimal over follow-up (37% in 2014) in the total population but higher (87%) in those under current rheumatologist care. The median time to DMARD in those seen by a rheumatologist improved from 49 days in 2000 to 23 days in 2009, with 34% receiving treatment within the 14-day benchmark. CONCLUSION This study describes the operationalization and reporting of national PMs using administrative data and identifies gaps in care to further examine and address.
- Published
- 2021
- Full Text
- View/download PDF
4. A Meta-Analysis of Case Fatality Rates of Recurrent Venous Thromboembolism and Major Bleeding in Patients with Cancer
- Author
-
Brooke Ballantyne Scott, Namali Ratnaweera, Elena Szefer, Alym Abdulla, Agnes Y.Y. Lee, and Wendy M Davis
- Subjects
0301 basic medicine ,medicine.medical_specialty ,Hemorrhage ,030204 cardiovascular system & hematology ,Risk Assessment ,03 medical and health sciences ,0302 clinical medicine ,Recurrence ,Neoplasms ,Internal medicine ,Case fatality rate ,medicine ,Humans ,Mortality ,Prospective cohort study ,Stroke ,Clinical Trials as Topic ,business.industry ,Incidence ,Incidence (epidemiology) ,Anticoagulants ,Venous Thromboembolism ,Hematology ,medicine.disease ,Thrombosis ,Confidence interval ,Regimen ,030104 developmental biology ,Relative risk ,business - Abstract
Background Knowing the case fatality rates of recurrent venous thromboembolism (VTE) and major bleeding is important for weighing the relative risks and benefits of anticoagulation and deciding on the duration of anticoagulant therapy, but these rates are uncertain in patients with cancer-associated thrombosis. Methods We performed a systematic review and a meta-analysis to determine the incidence of recurrent VTE and major bleeding and their respective case fatality rates in patients with cancer-associated VTE. Results Our analysis included 29 studies (15 prospective cohort studies and 14 randomized controlled trials) from 1980 to January 2019. Data from 8,000 cancer patients with 4,786 patient-years of follow-up were summarized. Rates of recurrent VTE and fatal recurrent VTE were 23.7 (95% confidence interval [CI]: 20.1–27.8) and 1.9 (95% CI: 0.8–4.0) per 100 patient-years of follow-up, respectively, with a case fatality rate of 14.8% (95% CI: 6.6–30.1%). The rates of major bleeding and fatal major bleeding events were 13.1 (95% CI: 10.3–16.7) and 0.8 (95% CI: 0.3–2.1) per 100 patient-years of follow-up, respectively, with a case fatality rate of 8.9% (95% CI: 3.5–21.1%). While the estimates of case fatality vary by anticoagulation regimen and study design, the differences between them were not statistically significant. Conclusion In cancer patients receiving anticoagulation, the case fatality rate of recurrent VTE is higher than the case fatality rate of major bleeding. These findings may help to inform decisions regarding the management of anticoagulation in patients with active cancer and VTE.
- Published
- 2020
- Full Text
- View/download PDF
5. Pregnancy Outcomes among Women Receiving rVSVΔ-ZEBOV-GP Ebola Vaccine during the Sierra Leone Trial to Introduce a Vaccine against Ebola
- Author
-
Rosalind J Carter, Olamide D Jarrett, Elena Szefer, Barbara E. Mahon, Mohamed Samai, Susan T. Goldstein, Sarah C. Tinker, Jennifer Legardy-Williams, and Augustin E Fombah
- Subjects
Pediatrics ,Epidemiology ,viruses ,lcsh:Medicine ,medicine.disease_cause ,Pregnancy Outcomes among Women Receiving rVSVΔ-ZEBOV-GP Ebola Vaccine during the Sierra Leone Trial to Introduce a Vaccine against Ebola ,Ebola virus ,0302 clinical medicine ,Pregnancy ,Medicine ,vaccine safety ,030212 general & internal medicine ,Pregnancy Complications, Infectious ,Uncategorized ,Ebola vaccine ,Vaccination ,Pregnancy Outcome ,virus diseases ,Prenatal Care ,Infectious Diseases ,Ebola ,Vaccine-preventable diseases ,Female ,Microbiology (medical) ,Adult ,medicine.medical_specialty ,Blinding ,030231 tropical medicine ,Ebola virus disease ,Prenatal care ,rVSVΔ-ZEBOV-GP ,Sierra leone ,lcsh:Infectious and parasitic diseases ,Sierra Leone ,03 medical and health sciences ,Young Adult ,Double-Blind Method ,West Africa ,Humans ,lcsh:RC109-216 ,Ebola Vaccines ,Sierra Leone Trial to Introduce a Vaccine against Ebola ,business.industry ,Research ,lcsh:R ,Hemorrhagic Fever, Ebola ,medicine.disease ,STRIVE ,vaccine-preventable diseases ,business - Abstract
Little information exists regarding Ebola vaccine rVSVΔGZEBOV-GP and pregnancy. The Sierra Leone Trial to Introduce a Vaccine against Ebola (STRIVE) randomized participants without blinding to immediate or deferred (18-24 weeks postenrollment) vaccination. Pregnancy was an exclusion criterion, but 84 women were inadvertently vaccinated in early pregnancy or became pregnant 15 days after vaccination) (45% [10/22]). No congenital anomalies were detected among 44 live-born infants examined. These data highlight the need for Ebola vaccination decisions to balance the possible risk for an adverse pregnancy outcome with the risk for Ebola exposure.
- Published
- 2020
6. Automated estimation of echocardiogram image quality in hospitalized patients
- Author
-
John Jue, Amir H. Abdi, Hany Girgis, Purang Abolmaesumi, Zhibin Liao, Elena Szefer, Pui Kee Lee, Robert Rohling, Teresa S.M. Tsang, Darby J. S. Thompson, Darwin F. Yeung, Michael Yin-Cheung Tsang, Parvathy Nair, Christina Luong, and Kenneth Gin
- Subjects
Adult ,Male ,medicine.medical_specialty ,Image quality ,media_common.quotation_subject ,Video Recording ,030204 cardiovascular system & hematology ,030218 nuclear medicine & medical imaging ,Correlation ,Machine Learning ,03 medical and health sciences ,Automation ,0302 clinical medicine ,Predictive Value of Tests ,Image Interpretation, Computer-Assisted ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Quality (business) ,Cardiac imaging ,media_common ,Aged ,Aged, 80 and over ,Ground truth ,Inpatients ,business.industry ,Reproducibility of Results ,Regression analysis ,Middle Aged ,Respiration, Artificial ,3. Good health ,Hospitalization ,Echocardiography ,Case-Control Studies ,Quality Score ,Physical therapy ,Feasibility Studies ,Female ,Cardiology and Cardiovascular Medicine ,business ,Unit-weighted regression - Abstract
We developed a machine learning model for efficient analysis of echocardiographic image quality in hospitalized patients. This study applied a machine learning model for automated transthoracic echo (TTE) image quality scoring in three inpatient groups. Our objectives were: (1) Assess the feasibility of a machine learning model for echo image quality analysis, (2) Establish the comprehensiveness of real-world TTE reporting by clinical group, and (3) Determine the relationship between machine learning image quality and comprehensiveness of TTE reporting. A machine learning model was developed and applied to TTEs from three matched cohorts for image quality of nine standard views. Case TTEs were comprehensive studies in mechanically ventilated patients between 01/01/2010 and 12/31/2015. For each case TTE, there were two matched spontaneously breathing controls (Control 1: Inpatients scanned in the lab and Control 2: Portable studies). We report the overall mean maximum and view specific quality scores for each TTE. The comprehensiveness of an echo report was calculated as the documented proportion of 12 standard parameters. An inverse probability weighted regression model was fit to determine the relationship between machine learning quality score and the completeness of a TTE report. 175 mechanically ventilated TTEs were included with 350 non-intubated samples (175 Control 1: Lab and 175 Control 2: Portable). In total, the machine learning model analyzed 14,086 echo video clips for quality. The overall accuracy of the model with regard to the expert ground truth for the view classification was 87.0%. The overall mean maximum quality score was lower for mechanically ventilated TTEs (0.55 [95% CI 0.54, 0.56]) versus 0.61 (95% CI 0.59, 0.62) for Control 1: Lab and 0.64 (95% CI 0.63, 0.66) for Control 2: Portable; p = 0.002. Furthermore, mechanically ventilated TTE reports were the least comprehensive, with fewer reported parameters. The regression model demonstrated the correlation of echo image quality and completeness of TTE reporting regardless of the clinical group. Mechanically ventilated TTEs were of inferior quality and clinical utility compared to spontaneously breathing controls and machine learning derived image quality correlates with completeness of TTE reporting regardless of the clinical group.
- Published
- 2020
7. Treatment patterns of in-patient spasticity medication use after traumatic spinal cord injury: a prospective cohort study
- Author
-
Kaila A. Holtz, Brian K. Kwon, Vanessa K. Noonan, Patricia Mills, and Elena Szefer
- Subjects
Adult ,Male ,Rehabilitation hospital ,030506 rehabilitation ,Pediatrics ,medicine.medical_specialty ,Adolescent ,medicine.medical_treatment ,Population ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Prevalence ,medicine ,Humans ,Prospective Studies ,Spasticity ,Practice Patterns, Physicians' ,Prospective cohort study ,education ,Spinal Cord Injuries ,Aged ,Retrospective Studies ,education.field_of_study ,Rehabilitation ,business.industry ,Medical record ,Trauma center ,Retrospective cohort study ,General Medicine ,Middle Aged ,Neuromuscular Agents ,Neurology ,Muscle Spasticity ,Female ,Neurology (clinical) ,medicine.symptom ,0305 other medical science ,business ,030217 neurology & neurosurgery - Abstract
Prospective cohort study using the Rick Hansen SCI Registry (RHSCIR) and retrospective medical chart review. To describe treatment patterns of in-patient anti-spasticity medication use following traumatic spinal cord injury (SCI) in acute and rehabilitation hospital settings in British Columbia, Canada. Quaternary trauma center, rehabilitation center. Individuals with traumatic SCI between 2005 and 2014 enrolled in the Vancouver RHSCIR site (N = 917) were eligible for inclusion. Oral and injectable anti-spasticity medication use were the main outcome measures. In 769 participants, higher neurological level and injury severity were associated with in-patient anti-spasticity medication use (p
- Published
- 2018
- Full Text
- View/download PDF
8. Abstracts and Workshops 7th National Spinal Cord Injury Conference November 9 – 11, 2017 Fallsview Casino Resort Niagara Falls, Ontario, Canada
- Author
-
Sarah Everhart-Skeels, Peter Athanasopoulos, Luc Noreau, David S. Ditor, Christiana L Cheng, Robert B. Shaw, Kristin E Musselman, Brian K. Kwon, Dimitri Krassiokov-Enns, Arlene Aspinall, Louise M Brisbois, Bastien Moineau, Shane N Sweet, Ryan G. L. Koh, Heather Flett, Bonita Sawatzky, Alison R. Oates, Lindsay Donaldson, Cyril Duclos, Robart Babona-Pilipos, Dalton L. Wolfe, Jillian Brooke, Lauren A Booker, Mikael F Del Castillo-Valenzuela, Tian Shen, Martha G Garcia-Garcia, Najib T. Ayas, Jaeeun Yoo, Shauna Cappe, Colleen O'Connell, Mohammad Alavinia, Rebecca L Bassett-Gunter, Jennifer Leo, Julio C. Furlan, Jerome Paquet, Tara Jeji, Marnie Graco, Karen Ethans, Julie Gagliardi, Sandra Mills, S Mohammad Alavinia, Jeremy M. Grimshaw, Karen Slonim, Kristin E. Musselman, Sander L Hitzig, Brian Drew, Cindy Gauthier, Brian Chan, Maureen Pakosh, Katherine Chan, Mark S. Nash, B. Catharine Craven, Mark Laylor, Cesar Marquez-Chin, Marcel F. Dvorak, Naaz Kapadia, Mary C. Verrier, Nader Fallah, Craig Bauman, Catherine Truchon, Minna Hong, Katie Lenz, Lyndsay Orr, Jeffrey G. Caron, Rebecca Charbonneau, Jasmine Arel, Micheal Namaka, Matija Milosevic, Patricia Mills, David J Berlowitz, Paul Holyoke, Anita Kaiser, Sivakumar Gulasingam, Keryn Chemtob, Audrey Roy, Colleen F. McGillivray, Jennifer W Howcroft, Lora Giangregorio, Carol Y. Scovil, Burns Anthony, Swati Mehta, Michael G. Fehlings, Jennifer Mokry, Renee Theiss, Mir Hatef Shojaei, Anne Harris, Austin J. Bergquist, Mary C Verrier, Manuel Jose Escalona Castillo, Andrea Townson, Dorothyann Curran, Parisa Sabetian, Suzanne M. Cadarette, Stephanie L Marrocco, Christiana Cheng, Lindsay Sleeth, Dahlia Kairy, Carly S. Rivers, Dany H. Gagnon, Toba B. Miller, Patricia Burns, Kristen Walden, David J. Allison, Walter Zelaya, Filomena Mazzella, Hardeep Singh, Mark Bayley, Barry Munro, Pamela Houghton, Jirapat Likitlersuang, Prashanth Velayudhan, Jean-François Lemay, Henry Ahn, Kathleen A. Martin Ginis, Kristina Guy, Samantha Taran, Matthew J. Stork, Bethlyn Houlihan, Amy E Latimer-Cheung, Jonathan C Mcleod, Maryleen K Jones, Kei Masani, Cynthia Morin, Elena Szefer, Vanessa K. Noonan, Joanne Zee, Paul B. Yoo, David G T Whitehurst, Antony D. Karelis, Bondi Moshe, Milos R Popovic, Gabriel Stefan, Helen Morris, Heather M. Flett, Rob Shaw, Stephanie Cornell, Murray Krahn, Megan K. MacGillivray, Susan Charlifue, Loretta M. Hillier, Rhonda Willms, A. G. Linassi, Rachel Schembri, Patrick Schneider, Shirin Shafazand, Eleni M Patsakos, Samantha Jeske, Janelle Unger, Roberta K. O'Shea, Jeremy Howcroft, Anna Kras-Dupuis, Eve C. Tsai, Indira Lanig, Milos R. Popovic, Farnoosh Farahani, Milad Alizadeh-Meghrazi, Jaya Sam, Jennifer R Tomasone, Tarun Arora, Clara Pujol, Emilie Michalovic, David Berlowitz, Debbie Hebert, Suzanne Humphreys, Ian D. Graham, Chris Alappat, Carolyn E. Schwartz, Tim Olds, Carmel Nicholls, Kelly P. Arbour-Nicitopoulos, Cindi M. Morshead, Shane McCullum, Alia Khan, Martin Vermette, Gerald Bilsky, Rachel Brosseau, Stacey Guy, Pamela E. Houghton, Anellina Ventre, Gillian Johnston, Ritu Sharma, Nancy Xia, Anthony S. Burns, Deena Lala, Purbasha Garai, Eldon Loh, Kathleen Martin Ginis, Joel S. Finkelstein, Sukhvinder Kalsi-Ryan, Michelle Sweeny, Maryam Omidvar, Patricia Bain, A. Gary Linassi, Julie Gassaway, Joseph Lee, Vera Zivanovic, H Dany Gagnon, Mylène Aubertin-Leheudre, Sadeghi Mahsa, Naaz Desai, Ethne L. Nussbaum, Chinnaya Thiyagarajan, Taufik A. Valiante, Jared Adams, John L.K. Kramer, Sunita Mathur, Meredith A Rocchi, José Zariffa, Louise Brisbois, Alan Casey, Tova Plashkes, Chester Ho, Ben Mortenson, Audrey L Hicks, James Milligan, Sharon Gabison, Sally Green, Melanie Kokotow, Sakina Valika, Meredith Rocchi, Kaila A. Holtz, Audrey L. Hicks, K. Alysse Bailey, Christopher West, Aaron Marquis, Sander L. Hitzig, Susan Cross, Nasrin Nejatbakhsh, Walter P. Wodchis, Samantha McRae, Stephanie N Iwasa, Nicole Mittmann, Livia P. Carvalho, Christine Short, Justine Baron, Masahiro Shinya, Heather L. Gainforth, Umalkhair Ahmed, Nikola Unic, Matthew R. Smith, Elizabeth Sumitro, and Christopher B McBride
- Subjects
Gerontology ,030506 rehabilitation ,business.industry ,MEDLINE ,medicine.disease ,03 medical and health sciences ,0302 clinical medicine ,Abstracts and Workshops ,Medicine ,Neurology (clinical) ,0305 other medical science ,business ,Spinal cord injury ,030217 neurology & neurosurgery ,Ontario canada - Abstract
First Place Award Submission - CA147Category: Clinical ApplicationManagement of obesity after spinal cord injury: a systematic reviewMir Hatef Shojaei1, Mohammad Alavinia1, B. Catharine Craven1,21N...
- Published
- 2017
- Full Text
- View/download PDF
9. A New QT Interval Correction Formulae to Adjust for Increases in Heart Rate
- Author
-
Elena Szefer, Simon W. Rabkin, and Darby J. S. Thompson
- Subjects
Male ,National health ,business.industry ,Large population ,Middle Aged ,030204 cardiovascular system & hematology ,QT interval ,Electrocardiography ,03 medical and health sciences ,Spline (mathematics) ,0302 clinical medicine ,Mathematical equations ,Heart Rate ,Heart rate ,Statistics ,Humans ,Medicine ,Female ,030212 general & internal medicine ,business ,Mathematics ,Aged - Abstract
This study sought to develop a formula from a large population-based study that best fit the QT-heart rate (HR) relationship independent of the standard mathematical relationships.Attempts to adjust or correct for the impact of HR on the QT interval (QTc) have applied various mathematical equations to electrocardiographic (ECG) data rather than allowing the data to determine the form of the relationship.A spline correction function was developed using the ECG data from NHANES (National Health and Nutrition Examination Surveys) II and III. The magnitude of linear, quadratic, and cubic trends in the relationship between HR and each QTc was quantified using an F-statistic with differences between QTcs compared using a permutation procedure.The effect of HR on QT was obliterated by the spline QT for both men and women. The cross-validated spline QTc was superior (i.e., flatter) to 6 other formulae, including ones proposed previously. In ECGs from the clinic with HRs faster than 70 beats/min, the QTcs from different formulae were significantly (p 0.0001) different from one another. Individual values suggest the use of the longest and shortest QTc intervals as developed originally. The new QTc and its population percentile ranking can be provided for clinical ECGs.A new QTc formula was developed which eliminates the relationship between QT and HR. At faster HRs, the 2 most commonly used QTcs provide numerical values at the extremes of QTc. Compared to existing formulae, the new formula had the best performance.
- Published
- 2017
- Full Text
- View/download PDF
10. Patient characteristics and long-term outcomes beyond the first 6 months after a diagnosis of cancer-associated venous thromboembolism
- Author
-
Nikolas Desilet, Namali Ratnaweera, Erica A. Peterson, Robert A. Schmidt, Elena Szefer, Agnes Y.Y. Lee, and Alaa A. Al Zaki
- Subjects
medicine.medical_specialty ,Patient characteristics ,Hemorrhage ,030204 cardiovascular system & hematology ,03 medical and health sciences ,0302 clinical medicine ,Recurrence ,Risk Factors ,Internal medicine ,Neoplasms ,medicine ,Long term outcomes ,Initial treatment ,Humans ,In patient ,Cumulative incidence ,Blood Coagulation ,business.industry ,Clinical course ,Cancer ,Anticoagulants ,Hematology ,Venous Thromboembolism ,medicine.disease ,030220 oncology & carcinogenesis ,business ,Venous thromboembolism - Abstract
Introduction Little is known about the clinical course and treatment decisions in patients with cancer-associated venous thromboembolism (VTE) beyond the initial treatment period of 3 to 6 months. This information is important for clinicians and patients to inform their decisions regarding duration of anticoagulation. Materials and methods We reviewed health records from consecutive patients referred to our institution for cancer-associated VTE management between 2013 and 2015 to describe their clinical course and outcomes from 6 to 24 months following their index VTE. Details on patient and cancer characteristics, objectively documented recurrent venous thromboembolism (rVTE), clinically relevant bleeding (CRB) and overall mortality were captured. Results 524 patients met eligibility criteria and 322 were alive at 6 months after the index VTE. At 6 months, anticoagulation was continued in 222 patients (68.9%). During follow-up, there were 33 rVTE events in 30 patients (1-year cumulative incidence of 8.2%; 95% CI: 5.5%–11.6%), and 16 CRB events in 15 patients (1-year cumulative incidence of 4.1%; 95% CI: 2.3%–6.7%); 20 (60.6%) rVTE events and 13 (81.3%) CRB events occurred while on anticoagulation. One-year survival beyond 6 months was 73.7% (95% CI: 68.5%–78.2%). A higher proportion of patients with advanced cancer and receiving cancer treatment was found among those who continued anticoagulation beyond 6 months compared to those who stopped anticoagulation. Conclusions Patients with cancer-associated VTE who are alive at 6 months after VTE diagnosis remain at high risk of rVTE, CRB and death.
- Published
- 2019
11. Early predictors of developing problematic spasticity following traumatic spinal cord injury: A prospective cohort study
- Author
-
Brian K. Kwon, Patricia Mills, Kaila A. Holtz, Vanessa K. Noonan, and Elena Szefer
- Subjects
Adult ,Male ,endocrine system ,030506 rehabilitation ,medicine.medical_specialty ,Traumatic spinal cord injury ,03 medical and health sciences ,0302 clinical medicine ,Physical medicine and rehabilitation ,Outcome Assessment, Health Care ,Medicine ,Humans ,Spasticity ,Prospective Studies ,Registries ,Prospective cohort study ,Spinal cord injury ,Research Articles ,Spinal Cord Injuries ,Retrospective Studies ,Models, Statistical ,business.industry ,Reproducibility of Results ,Middle Aged ,medicine.disease ,Prognosis ,Muscle Spasticity ,Observational study ,Female ,Neurology (clinical) ,medicine.symptom ,0305 other medical science ,business ,030217 neurology & neurosurgery - Abstract
Objective: To identify early predictors and develop reliable, validated prediction models for development of problematic spasticity after traumatic spinal cord injury (SCI). Design: Prospective cohort study of the Rick Hansen Spinal Cord Injury Registry (RHSCIR), retrospective review of inpatient medical charts. Setting: Quaternary trauma center, rehabilitation center, community settings. Participants: Individuals with traumatic SCI between March 1, 2005, and March 31, 2014, prospectively enrolled in the Vancouver site RHSCIR. Interventions: None. Main Outcome Measure: Spasticity limiting function or requiring treatment (problematic spasticity) on the Spinal Cord Injury Health Questionnaire. Results: In 350 patients, variables documented during hospitalization that predicted the development of problematic spasticity up to 5 years post-injury included: initial Glasgow Coma Scale; age at time of injury; admission to rehabilitation center; community discharge anti-spasticity medication prescription, neurological status, Penn Spasm Frequency Scale, and pain interference with quality of life, sleep, activities; greater change in AIS motor scores between admission and discharge. The predictive models had area under the receiver operating characteristic curve of 0.80 (95% CI 0.75, 0.85) in the development set (N = 244) and 0.84 (95% CI 0.74, 0.92) in the validation set (N = 106) for spasticity limiting function and 0.81 (95% CI 0.76, 0.85) in the development set and 0.85 (95% CI 0.77, 0.92) in the validation set for spasticity requiring treatment. Conclusions: Our prediction models provide an early prognosis of risk of developing problematic spasticity after traumatic SCI, which can be used to improve clinical spasticity management and assist research (e.g. risk stratification in interventional trials).
- Published
- 2018
12. THU0646 Evaluating the quality of care for rheumatoid arthritis
- Author
-
Deborah A. Marshall, Diane Lacaille, Elena Szefer, Claire E.H. Barber, and Darby J. S. Thompson
- Subjects
musculoskeletal diseases ,medicine.medical_specialty ,Percentile ,business.industry ,Incidence (epidemiology) ,Arthritis ,medicine.disease ,Rheumatology ,New onset ,Rheumatoid arthritis ,Internal medicine ,Cohort ,medicine ,Quality of care ,business - Abstract
Background The Arthritis Alliance of Canada (AAC) has developed performance measures (PMs) to evaluate RA care quality. Objectives To operationalize and report on 4 PMs using administrative data for British Columbia (BC), Canada: PM1) percentage of patients with new onset RA with at least one visit to a rheumatologist in the first year after diagnosis, PM2) percentage of RA patients under the care of a rheumatologist seen in follow-up at least once per year, PM3) percentage of RA patients dispensed a disease modifying anti-rheumatic drug (DMARD) during the measurement year, PM4) time to DMARD therapy in new onset RA. Methods All patients with RA visits between 01/01/1997 and 31/12/2009 in BC were identified using health administrative data and followed until December 2014. Cases were identified by ≥2 physician billing codes for RA ≥8 weeks but ≤5 years apart. For this study, only cases age >18 who were seen by a rheumatologist at some point over follow-up were included. PM1: The percentage of incident RA cases with at least one visit to a rheumatologist within one year of their first RA visit was evaluated. PM2: The proportion of prevalent RA cases having at least one visit per year was calculated for those under rheumatology care. PM3: The percentage of prevalent RA patients dispensed a DMARD (including biologic agents and small molecule inhibitors) was calculated. PM4: time from RA onset (defined as first RA visit) to DMARD therapy was reported (in the calendar year of RA incidence), using median and 90th percentile wait time, as well as the proportion meeting the benchmark of 14 days. Results The cohort included 18 976 incident and 29 639 prevalent RA cases. The percentage of patients seen by a rheumatologist within 1 year from RA diagnosis increased over time, while the percentage of RA patients under the care of a rheumatologist seen in yearly follow-up declined steadily overtime. Further analysis (data not shown) suggests this is due to having more people with longer follow-up in the latter years, and lost to follow-up increasing over time, rather than a true calendar year effect. The percentage of RA patients dispensed a DMARD was suboptimal (56%>65%). Of note, patients were not necessarily seen by a rheumatologist during the measurement year. The median time to DMARD improved over time to 23 days in 2009, with roughly one third receiving a DMARD within the benchmark of 14 days. Conclusions The present study represents the first time the AAC’s PMs have been tested in administrative data and highlights where the measures are being met and potential gaps in care which require further examination. Disclosure of Interest None declared
- Published
- 2018
- Full Text
- View/download PDF
13. Randomized trial comparing the safety and antibody responses to live attenuated versus inactivated influenza vaccine when administered to breastfeeding women
- Author
-
Mark C. Steinhoff, Monica M. McNeal, Lisa A. Jackson, Mark Wolff, Emmanuel B. Walter, Elena Szefer, David I. Bernstein, Geeta K. Swamy, Elizabeth P. Schlaudecker, Andi L. Shane, Sharon E. Frey, and Rebecca C. Brady
- Subjects
Adult ,Male ,Adolescent ,Influenza vaccine ,Breastfeeding ,Breast milk ,Placebo ,Antibodies, Viral ,Vaccines, Attenuated ,Injections, Intramuscular ,Article ,law.invention ,Placebos ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,Randomized controlled trial ,Double-Blind Method ,law ,030225 pediatrics ,Medicine ,Live attenuated influenza vaccine ,Humans ,030212 general & internal medicine ,Administration, Intranasal ,Hemagglutination assay ,General Veterinary ,General Immunology and Microbiology ,Milk, Human ,business.industry ,Immunogenicity ,Public Health, Environmental and Occupational Health ,Infant, Newborn ,Infant ,Middle Aged ,Orthomyxoviridae ,Immunoglobulin A ,Infectious Diseases ,Breast Feeding ,Vaccines, Inactivated ,Influenza Vaccines ,Immunoglobulin G ,Immunology ,Antibody Formation ,Molecular Medicine ,Female ,business - Abstract
Background Live attenuated influenza vaccine (LAIV) and inactivated influenza vaccine (IIV) are both licensed for administration to nursing mothers. Little is known about the potential for transmission of LAIV viruses from the mother to the infant and the comparative breast milk antibody responses to LAIV and IIV. Methods We performed a randomized, double-blind study comparing the immunogenicity of LAIV to IIV when administered to nursing mothers. The safety of LAIV to IIV in women and their infants was also compared. Women received LAIV + intramuscular placebo, or IIV + intranasal placebo on Day 0. Breast milk and nasal swabs (from women and infants) were collected on Days 0, 2, and 8 for detection of LAIV. Breast milk and serum antibody responses were measured at Days 0 and 28. The primary hypothesis was that LAIV would provide superior induction of breast milk IgA responses to influenza as compared to IIV when administered to nursing mothers. Results Breast milk IgG, breast milk IgA (H1N1 only), serum hemagglutination inhibition (HAI), and serum IgG responses were significantly higher following administration of IIV compared to LAIV. Receipt of either LAIV or IIV was safe in women and their infants. One (1%) LAIV recipient transmitted vaccine virus to her infant who remained well. No influenza virus was detected in breast milk. Conclusions Breast milk and serum antibody responses were higher for IIV compared to LAIV. LAIV and IIV were safe for nursing women but there was one (1%) possible transmission of LAIV to an infant. This study suggests that IIV may be the preferred vaccine for nursing mothers.
- Published
- 2017
14. Multivariate association between single-nucleotide polymorphisms in Alzgene linkage regions and structural changes in the brain: discovery, refinement and validation
- Author
-
Jinko Graham, Mirza Faisal Beg, Elena Szefer, Farouk S. Nathoo, and Donghuan Lu
- Subjects
RV coefficient ,0301 basic medicine ,Statistics and Probability ,Multivariate analysis ,Genetic Linkage ,Imaging genetics ,Library science ,Single-nucleotide polymorphism ,Biology ,Polymorphism, Single Nucleotide ,Meso scale ,03 medical and health sciences ,0302 clinical medicine ,Alzheimer Disease ,Missing heritability problem ,Political science ,Health care ,Image Processing, Computer-Assisted ,Genetics ,Humans ,Cognitive decline ,Molecular Biology ,Alleles ,030304 developmental biology ,Linkage (software) ,Brain Mapping ,0303 health sciences ,business.industry ,Brain ,Reproducibility of Results ,Magnetic Resonance Imaging ,Minor allele frequency ,Computational Mathematics ,030104 developmental biology ,Multivariate Analysis ,business ,Engineering research ,030217 neurology & neurosurgery ,Genome-Wide Association Study - Abstract
Both genetic variants and brain region abnormalities are recognized to play a role in cognitive decline. We explore the association between singlenucleotide polymorphisms (SNPs) in linkage regions for Alzheimer’s disease and rates of decline in brain structure using data from the Alzheimers Disease Neuroimaging Initiative (ADNI).In an initial discovery stage, we assessed the presence of linear association between the minor allele counts of 75,845 SNPs in the Alzgene linkage regions and predicted rates of change in structural MRI measurements for 56 brain regions using an RV test. In a second, refinement stage, we reduced the number of SNPs using a bootstrap-enhanced sparse canonical correlation analysis (SCCA) with a fixed tuning parameter. Each SNP was assigned an importance measure proportional to the number of times it was estimated to have a nonzero coefficient in repeated re-sampling from the ADNI-1 sample. We created refined lists of SNPs based on importance probabilities greater than 50% and 90%, respectively. In a third, validation stage, we assessed the multivariate association between these refined lists of SNPs and the rates of structural change in the independent ADNI-2 study dataset.There was strong statistical evidence for linear association between the SNPs in the Alzgene linkage regions and the 56 imaging phenotypes in both the ADNI-1 and ADNI-2 samples (p < 0.0001). The bootstrap-enhanced SCCA identified 1,694 priority SNPs with importance probabilities > 50% and 22 SNPs with importance probabilities > 90%. The 1,694 prioritized SNPs in the ADNI-1 data were associated with imaging phenotypes in the ADNI-2 data (p = 0.0021).This manuscript presents an analysis that addresses challenges in current imaging genetics studies such as biased sampling designs and highdimensional data with low-signal. Genes corresponding to priority SNPs having the highest contribution in the validation data have previously been implicated or hypothesized to be implicated in AD, including GCLC, IDE, and STAMBP1andFAS. We hypothesize that the effect sizes of the 1,694 SNPs in the priority set are likely small, but further investigation within this set may advance understanding of the missing heritability in late-onset Alzheimers disease. Multivariate analysis; Linkage regions; Imaging genetics; Endophenotypes; Inverse probability weighting; Variable importance probabilities
- Published
- 2017
- Full Text
- View/download PDF
15. A Bayesian Group Sparse Multi-Task Regression Model for Imaging Genetics
- Author
-
Jinko Graham, Keelin Greenlaw, Mary Lesperance, Elena Szefer, and Farouk S. Nathoo
- Subjects
FOS: Computer and information sciences ,0301 basic medicine ,Statistics and Probability ,Shrinkage estimator ,Multivariate statistics ,Genotyping Techniques ,Computer science ,Interval estimation ,Bayesian probability ,Inference ,Machine Learning (stat.ML) ,Neuroimaging ,computer.software_genre ,01 natural sciences ,Biochemistry ,Regularization (mathematics) ,Polymorphism, Single Nucleotide ,Statistics - Applications ,Methodology (stat.ME) ,010104 statistics & probability ,03 medical and health sciences ,Alzheimer Disease ,Statistics - Machine Learning ,Linear regression ,Statistical inference ,Bayesian hierarchical modeling ,Humans ,Applications (stat.AP) ,Point estimation ,0101 mathematics ,Molecular Biology ,Statistics - Methodology ,Models, Statistical ,Estimator ,Brain ,Regression analysis ,Bayes Theorem ,Genomics ,Original Papers ,Computer Science Applications ,Computational Mathematics ,030104 developmental biology ,Computational Theory and Mathematics ,Cohort ,Data mining ,computer ,Algorithms ,Software - Abstract
Motivation Recent advances in technology for brain imaging and high-throughput genotyping have motivated studies examining the influence of genetic variation on brain structure. Wang et al. have developed an approach for the analysis of imaging genomic studies using penalized multi-task regression with regularization based on a novel group l2,1-norm penalty which encourages structured sparsity at both the gene level and SNP level. While incorporating a number of useful features, the proposed method only furnishes a point estimate of the regression coefficients; techniques for conducting statistical inference are not provided. A new Bayesian method is proposed here to overcome this limitation. Results We develop a Bayesian hierarchical modeling formulation where the posterior mode corresponds to the estimator proposed by Wang et al. and an approach that allows for full posterior inference including the construction of interval estimates for the regression parameters. We show that the proposed hierarchical model can be expressed as a three-level Gaussian scale mixture and this representation facilitates the use of a Gibbs sampling algorithm for posterior simulation. Simulation studies demonstrate that the interval estimates obtained using our approach achieve adequate coverage probabilities that outperform those obtained from the nonparametric bootstrap. Our proposed methodology is applied to the analysis of neuroimaging and genetic data collected as part of the Alzheimer’s Disease Neuroimaging Initiative (ADNI), and this analysis of the ADNI cohort demonstrates clearly the value added of incorporating interval estimation beyond only point estimation when relating SNPs to brain imaging endophenotypes. Availability and Implementation Software and sample data is available as an R package ‘bgsmtr’ that can be downloaded from The Comprehensive R Archive Network (CRAN). Supplementary information Supplementary data are available at Bioinformatics online.
- Published
- 2016
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.