Abstract P150: Association Of Leisure Time Physical Activity (LTPA) With Left Atrial Function In Older Adults: The Atherosclerosis Risk In Communities (ARIC) Study

Abstract

Introduction: Prior research indicates that higher LTPA is associated with better left ventricular (LV) diastolic function, but not with left atrial volume index (LAVI). Left atrial (LA) strain is a more sensitive marker of LA pathology. Hence, we evaluated association of LTPA with LA strain in the ARIC study, a community-based cohort study. Hypothesis: Higher LTPA is associated with better LA reservoir, conduit and contractile function. Methods: We included 4005 participants (mean age 75 years, 63% female, 21% black) with 2D echocardiographic (2DE) LA % strain data, LTPA data, and without prevalent coronary heart disease, valvular heart disease, heart failure, atrial fibrillation, and stroke at Visit 5 (V5, 2011-13). We estimated LTPA as metabolic equivalent-minutes per week from validated Baecke questionnaire and categorized it as poor, intermediate, or ideal as per AHA recommendation. We categorized change in LTPA from V3 (1993-95) to V5 as persistently poor (referent), decreasing, increasing, or persistently active. LA reservoir, conduit, and contractile % strain were measured from speckle-tracking 2DE. Linear regression was used to evaluate association of LTPA with LA function. We modeled LTPA (1) cross-sectionally at V5 as a continuous variable and (2) change from V3 to V5, as continuous and categorical variables (referent- persistently poor). Results: Higher LTPA at V5 (Table) and persistently high (vs poor) LTPA from V3 to 5 (β estimate -0.89, 95% CI -1.40, -0.38) were significantly associated with better LA conduit function after adjusting for CV risk factors, LV function, and LAVI. The same associations with LA reservoir function were no longer significant after adjusting for CV risk factors. LTPA was not associated with LA contractile function (Table). Conclusions: Consistent with LTPA’s salutary effect on LV diastolic function, higher LTPA is associated with better LA conduit function. Maintaining high LTPA from midlife to late-life may be beneficial in mitigating age-related changes in cardiac function.