Abstract P161: Accelerometer-Measured Physical Activity and Heart Failure Incidence in Women Ages 63-99 Years: The OPACH Study

Abstract

Background: The burden of heart failure (HF) is increasing in older adults, yet optimal treatment options are not available. Therefore, prevention efforts are paramount to population HF control. Physical activity (PA) has been associated with lower HF incidence, however few studies have evaluated older women and none have measured PA using accelerometry. We prospectively examined 6,173 multiethnic (White, 49%; Black, 34%; Hispanic, 17%) women ages 63-99 (mean 78.6) without known HF at baseline in the Objective Physical Activity and Cardiovascular Health Study. Methods: Vector magnitude counts/15-sec epoch from hip worn Actigraph GT3X+ triaxial accelerometers (required ≥4 of 7 days with ≥10 hr/day wear time) were used to define time spent in light (LPA; 19-518 counts/15-sec), moderate-to-vigorous (MVPA; ≥519), and total (average VM counts across wear days) PA. Count cutpoints were determined from a calibration study among similarly aged women. Incident HF cases were ascertained by self-report annually and were adjudicated by medical record review. Cases of hospitalized acute decompensated HF were included here. Cox regression was used to estimate hazard ratios (HR) and 95% confidence intervals (CI) for these associations. Results: There were 213 (3.5%) incident HF cases identified during a mean 4.5 year follow-up. Crude HF rates (per 1000 person-years) across PA tertiles were 13.2, 5.7, and 4.9 for total PA; 12.3, 5.4, and 5.8 for light PA; and 14.8, 6.1, and 3.3 for MVPA. After adjusting for awake wear time, age, race, ethnicity, smoking, comorbidities including CHD, diabetes and hypertension, and self-rated health, the HR comparing the highest to lowest tertile was 0.61 (0.42, 0.89) for total PA, 0.69 (0.48, 0.98) for light PA, and 0.39 (0.25, 0.59) for MVPA. After adjusting for these covariates and for PA intensity, among all women the HR for a 30-min/day increment in light PA was 0.93 (0.88, 0.99) and in MVPA was 0.73 (0.59, 0.88). Similar magnitudes of inverse associations with HF risk for light PA and MVPA were seen in women <80 and ≥80 years of age, and in women with low physical function (SF36 score <60) and with higher function (≥60). Inverse associations with HF for light PA and MVPA also were seen in white (HR = 0.94 and 0.78), black (HR = 0.92 and 0.58) and Hispanic (HR = 0.97 and 0.65) women, and in those who were obese (BMI ≥30; HR = 0.93 and 0.81) and not obese (HR = 0.93 and 0.54), although HRs across these stratum were more variable. Results among all women were materially the same after discarding HF cases occurring during the first year of follow-up. Conclusions: Greater levels of accelerometer-measured total, light intensity and moderate-to-vigorous intensity PA were associated with lower incidence of HF in older community-living women. These findings underscore the potential public health relevance of being physically active in later life for primary HF prevention.