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Background: Few longitudinal studies have delineated the association between traditional cardiovascular risk factors and development of aortic stenosis (AS)., Objectives: The authors examined the association between traditional cardiovascular risk factors and incident severe AS in a large, unselected elderly population., Methods: This observational cohort study used multiple linked health care population-based databases of individuals older than 65 years on April 1, 2002, without prior valvular disease, coronary artery disease, heart failure, cardiac arrhythmia, cerebrovascular disease, congenital heart disease, or admissions with cardiac symptoms. The relationship between hypertension (HTN), diabetes, dyslipidemia, and incident severe AS requiring hospitalization or surgical or interventional treatment was examined., Results: Among 1.12 million individuals followed for a median of 13 years, 20,995 subjects developed severe AS. Overall absolute incidence was 144 per 100,000 person-years (169 and 127 per 100,000 person-years in men and women, respectively). In cause-specific hazard models, HTN (adjusted hazard ratio [HR]: 1.71; 95% confidence interval [CI]: 1.66 to 1.76), diabetes (HR: 1.49; 95% CI: 1.44 to 1.54), and dyslipidemia (HR: 1.17; 95% CI: 1.14 to 1.21) were all significantly associated with increased risk of developing severe AS (all p < 0.001). There was a positive dose-response relationship between the number and duration of cardiac risk factors and risk of AS. In the Fine-Gray model, all 3 risk factors were independently associated with a higher incidence of AS. The population-attributable risk of AS associated with 3 cardiac risk factors was 34.4% (95% CI: 32.8 to 36.0)., Conclusions: HTN, diabetes, and dyslipidemia have independent and dose-response associations with incident AS in an unselected population of older individuals, and together accounted for approximately one-third of the incidence of severe AS., (Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Background: The prognostic importance of high-density lipoprotein cholesterol (HDL-C) as a specific risk factor for cardiovascular (CV) disease has been challenged by recent clinical trials and genetic studies., Objectives: This study sought to reappraise the association of HDL-C level with CV and non-CV mortality using a "big data" approach., Methods: An observational cohort study was conducted using the CANHEART (Cardiovascular Health in Ambulatory Care Research Team) dataset, which was created by linking together 17 different individual-level data sources. People were included if they were between 40 and 105 years old on January 1, 2008, living in Ontario, Canada, without previous CV conditions or severe comorbidities, and had an outpatient fasting cholesterol measurement in the year prior to the inception date. The primary outcome was cause-specific mortality., Results: A total of 631,762 individuals were included. The mean age of our cohort was 57.2 years, 55.4% were women, and mean HDL-C level was 55.2 mg/dl. There were 17,952 deaths during a mean follow-up of 4.9 ± 0.4 years. The overall all-cause mortality rate was 8.1 per 1,000 person-years for men and 6.6 per 1,000 person-years for women. Individuals with lower HDL-C levels were more likely to have low incomes, unhealthy lifestyle, higher triglycerides levels, other cardiac risk factors, and medical comorbidities. Individuals with lower HDL-C levels were independently associated with higher risk of CV, cancer, and other mortality compared with individuals in the reference ranges of HDL-C levels. In addition, individuals with higher HDL levels (>70 mg/dl in men, >90 mg/dl in women) had increased hazard of non-CV mortality., Conclusions: Complex associations exist between HDL-C levels and sociodemographic, lifestyle, comorbidity factors, and mortality. HDL-C level is unlikely to represent a CV-specific risk factor given similarities in its associations with non-CV outcomes., (Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.)

Objectives: We evaluated whether appropriateness and baseline risk of cardiac catheterization varied according to regional intensity of invasive therapy after acute myocardial infarction (AMI), and whether AMI mortality varied according to invasive intensity regions., Background: Marked regional variations exist in cardiac invasive procedure use after AMI within the U.S., Methods: We performed an analysis of 44,639 Medicare fee-for-service beneficiaries hospitalized with AMI between 1998 and 2001. Invasive procedure intensity was determined based on overall cardiac catheterization rates for Medicare enrollees. Cardiac catheterization appropriateness was determined by the American College of Cardiology/American Heart Association classification and baseline risk was estimated using the GRACE (Global Registry of Acute Coronary Events) risk score. The primary outcomes of the study were cardiac catheterization use within 60 days and 3-year mortality after hospital admission., Results: Higher invasive intensity regions were more likely to perform cardiac catheterizations on class I patients (appropriate) (RR 1.38, 95% confidence interval [CI] 1.27 to 1.48), class II patients (equivocal) (RR 1.42, 95% CI 1.31 to 1.53), and class III patients (inappropriate) (RR 1.29, 95% 0.97 to 1.67) compared with low-intensity regions after adjusting for patient and physician characteristics. The overall cardiac catheterization use was 5.2% lower for each increase in GRACE risk decile, and this relationship was observed similarly in all regions. Risk-standardized mortality rates of AMI patients at 3 years were not substantially different between regions., Conclusions: Although higher-risk patients and those with more appropriate indications may have the most to benefit from an invasive strategy after AMI, we found that higher-invasive regions do not differentiate procedure selection based on the patients' appropriateness or their baseline risks.

Objectives: We sought to examine outcomes in recipients of implantable cardioverter-defibrillators (ICDs) and the effect of age, gender, and comorbidities on survival., Background: Age, gender, and comorbidities may significantly affect outcomes in ICD recipients., Methods: We examined factors associated with mortality in 2,467 ICD recipients in Ontario, Canada, using a province-wide database. Comorbidities were identified retrospectively by examining all diagnosis codes within the 3 years before implant., Results: Mean ages at ICD implant were 63.2 +/- 12.5 years (1,944 men) and 59.8 +/- 15.9 years (523 women). Mortality rates at one and 2 years were 7.8% and 14.0%. Older age at implant increased the risk of death with hazard ratios (HR) of 2.05 (95% confidence interval [CI] 1.70 to 2.47) and 3.00 (95% CI 2.43 to 3.71) for those 65 to 74 years and >/=75 years, respectively (both p < 0.001), but gender was not a predictor of death. Common noncardiac conditions associated with death included peripheral vascular disease (adjusted HR 1.50, 95% CI 1.18 to 1.91), pulmonary disease (adjusted HR 1.35, 95% CI 1.10 to 1.66), and renal disease (adjusted HR 1.57, 95% CI 1.25 to 1.99). Many ICD recipients had prior heart failure (46.2%) with an increased HR of 2.33 for death (95% CI 1.96 to 2.76; p < 0.001). Greater comorbidity burden conferred increased risk, with HRs adjusted for age, gender, and heart failure of 1.72 (95% CI 1.44 to 2.05), 2.79 (95% CI 2.15 to 3.62), and 2.98 (95% CI 1.74 to 5.10) for those with 1, 2, and 3 or more noncardiac comorbidities, respectively (all p < 0.001)., Conclusions: Age, noncardiac comorbidities, and prior heart failure influence survival outcomes in ICD recipients. These factors should be considered in the care of ICD recipients.

Objectives: This study was designed to determine whether admission to a Canadian hospital with on-site revascularization (invasive hospital) affected revascularization choice, timing, and outcome compared with community (non-invasive) hospitals., Background: Health care systems in Canada are characterized by relative restraint in diffusion of tertiary cardiovascular services, with capacity for revascularization procedures concentrated in large regional referral centers., Methods: We used linked administrative data and a clinical registry to follow-up 15,166 Ontario patients who underwent revascularization within the year after their index acute myocardial infarction (MI). Outcomes included recurrent urgent cardiac hospitalization, hospital bed-days, and death within the same year after the index admission. We adjusted for age, gender, socioeconomic status, illness severity, attending physician specialty, and academic hospital affiliation., Results: After adjusting for baseline factors, patients admitted to invasive hospitals were more likely to receive angioplasty than bypass surgery (adjusted odd ratio: 1.85; 95% confidence interval: 1.68 to 2.04, p < 0.001). The converse pattern was seen for patients admitted to community hospitals. Median revascularization waiting times were significantly shorter at invasive hospitals (12 vs. 48 days, p < 0.001). Patients admitted to invasive hospitals had fewer cardiac re-admissions (41.5 vs. 68.9 events per 100 patients, p < 0.001) before their first revascularization and consumed fewer hospital bed-days (379 vs. 517 per 100 patients, p < 0.001). There were no differences in outcomes beyond revascularization., Conclusions: Outcome advantages associated with timely post-MI revascularization highlight the importance of organizing revascularization referral networks and facilitating access to revascularization for patients with acute coronary syndromes admitted to community hospitals in Canada.

Objectives: The aim of this study was to compare the effectiveness of the implantable cardioverter defibrillator (ICD) and medical strategies for prevention of arrhythmic events and death., Background: The ICD is a potential strategy to reduce mortality in patients at risk of sudden death., Methods: The MEDLINE, EMBASE, and Cochrane Library electronic databases were searched from January 1966 to April 2002. All published randomized controlled trials comparing ICD implantation with medical therapy were reviewed. Four independent reviewers extracted data on all-cause mortality, nonarrhythmic death, and arrhythmic death using a standardized protocol., Results: Nine studies including over 5,000 patients were synthesized using both fixed-effects and random-effects models. The primary and secondary prevention trials showed a significant benefit of the ICD with respect to arrhythmic death, with relative risks (RR) of 0.34 and 0.50, respectively (both p < 0.001). The mortality benefit of the ICD was entirely attributable to a reduction in arrhythmic death (all trials: p < 0.00001). Whereas the secondary prevention trials exhibited a robust decrease in all-cause ICD mortality (RR 0.75; p < 0.001), the pooled primary prevention trials demonstrated decreased all-cause ICD mortality (RR 0.66; p < 0.05) which was dependent on selected individual trials. The disparity in ICD-related mortality reductions in the primary prevention trials was related to variability in the incidence of arrhythmic death between individual studies., Conclusions: Although the ICD decreases the risk of arrhythmic death, its impact on all-cause mortality is related to the underlying risk of arrhythmia-related death relative to competing causes. Given the cost of the device strategy, policies of targeted intervention based on the future risk of arrhythmia are warranted.

Objectives: The goal of our study was to examine how age and gender affect the use of coronary angiography and the intensity of cardiac follow-up care within the first year after acute myocardial infarction (AMI). Another objective was to evaluate the association of age, gender and treatment intensity with five-year survival after AMI., Background: Utilization rates of specialized cardiac services inversely correlate with age. Gender-specific practice patterns may also vary with age in a manner similar to known age-gender survival differences after AMI., Methods: Using linked population-based administrative data, we examined the association of age and gender with treatment intensity and long-term survival among 25,697 patients hospitalized with AMI in Ontario between April 1, 1992, and December 31, 1993. A Cox proportional hazards model was used to adjust for socioeconomic status, illness severity, attending physician specialty and admitting hospital characteristics., Results: After adjusting for baseline differences, the relative rates of angiography and follow-up specialist care for women relative to men, respectively, fell 17.5% (95% confidence interval [CI], 13.6 to 21.3, p < 0.001) and 10.2% (95% CI, 7.1 to 13.2, p < 0.001) for every 10-year increase in age. Conversely, long-term AMI survival rates in women relative to men improved with increasing age, such that the relative survival in women rose 14.2% (95% CI, 10.1 to 17.5, p < 0.001) for every 10-year age increase., Conclusions: Gender differences in the intensity of invasive testing and follow-up care are strongly age-specific. While care becomes progressively less aggressive among older women relative to men, survival advantages track in the opposite direction, with older women clearly favored. These findings suggest that biology is likely to remain the main determinant of long-term survival after AMI for women.