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Background: Evidence that higher sedentary time is associated with higher risk for cardiovascular disease (CVD) is based mainly on self-reported measures. Few studies have examined whether patterns of sedentary time are associated with higher risk for CVD., Methods: Women from the Objective Physical Activity and Cardiovascular Health (OPACH) Study (n=5638, aged 63-97, mean age=79±7) with no history of myocardial infarction (MI) or stroke wore accelerometers for 4-to-7 days and were followed for up to 4.9 years for CVD events. Average daily sedentary time and mean sedentary bout duration were the exposures of interest. Cox regression models estimated hazard ratios (HR) and 95% confidence intervals (CI) for CVD using models adjusted for covariates and subsequently adjusted for potential mediators (body mass index (BMI), diabetes, hypertension, and CVD-risk biomarkers [fasting glucose, high-density lipoprotein, triglycerides, and systolic blood pressure]). Restricted cubic spline regression characterized dose-response relationships., Results: There were 545 CVD events during 19,350 person-years. Adjusting for covariates, women in the highest (≥ ~11 hr/day) vs. the lowest (≤ ~9 hr/day) quartile of sedentary time had higher risk for CVD (HR=1.62; CI=1.21-2.17; p-trend <0.001). Further adjustment for potential mediators attenuated but did not eliminate significance of these associations (p-trend<.05, each). Longer vs. shorter mean bout duration was associated with higher risks for CVD (HR=1.54; CI=1.27-2.02; p-trend=0.003) after adjustment for covariates. Additional adjustment for CVD-risk biomarkers attenuated associations resulting in a quartile 4 vs. quartile 1 HR=1.36; CI=1.01-1.83; p-trend=0.10). Dose-response associations of sedentary time and bout duration with CVD were linear (P-nonlinear >0.05, each). Women jointly classified as having high sedentary time and long bout durations had significantly higher risk for CVD (HR=1.34; CI=1.08-1.65) than women with both low sedentary time and short bout duration. All analyses were repeated for incident coronary heart disease (MI or CVD death) and associations were similar with notably stronger hazard ratios., Conclusions: Both high sedentary time and long mean bout durations were associated in a dose-response manner with increased CVD risk in older women, suggesting that efforts to reduce CVD burden may benefit from addressing either or both component(s) of sedentary behavior., Competing Interests: DISCLOSURES The authors maintain that there are no conflicts of interest associated with this manuscript.

Background: Good lower extremity physical functioning is paramount to healthy aging as it prevents social isolation, enables civic engagement, and facilitates physical activity. Strong evidence links physical functioning with all-cause mortality, but little is known about its relationship to cardiovascular disease (CVD). Methods: Women (n=5043, mean age=79±7) with no history of myocardial infarction or stroke completed the Short Physical Performance Battery (SPPB) consisting of three timed tasks to assess standing balance, strength (5 chair stands), and gait (4m walk). Results were summarized using prespecified cutpoints yielding a score from 0 (worst) to 12 (best). Women were followed for CVD events for up to 6 years. Hazard ratios (HR) were estimated for women with poor, low, moderate, and high functioning (respective SPPB ranges for each group; 0-3, 4-6, 7-9, and 10-12) using Cox proportional hazard models adjusted for several covariates including accelerometer-measured moderate to vigorous physical activity (MVPA) and sedentary behavior. Effect modification of associations between SPPB and CVD by age, MVPA, Reynolds Risk Score, race-ethnicity, and self-rated health were tested by including multiplicative interaction terms in fully adjusted Cox models with statistical significance for interactions set to 0.10. Results: Covariate-adjusted HRs (95% CIs) for CVD [ 1.00 (ref.); 0.85 (0.62, 1.15); 0.69 (0.51, 0.93); 0.49 (0.35, 0.68)] and CVD mortality [ 1.00 (ref.); 0.72 (0.45, 1.15); 0.44 (0.27, 0.72); 0.35 (0.19, 0.62)] decreased across poor, low, moderate, and high SPPB subgroups, respectively (p-trend<.001 [ABSTRACT FROM AUTHOR]