Abstract TMP46: Self-reported Physical Activity Frequency and Risk of Incident Stroke in the REasons for Geographic and Racial Differences in Stroke (REGARDS) Study

Abstract

Background and Purpose: Adherence to a healthy lifestyle is known to reduce stroke risk, and regular physical activity is an important recommendation for stroke prevention. We compared the associations of self-reported physical activity (PA) with incident stroke in the REasons for Geographic And Racial Differences in Stroke (REGARDS) study. Methods: REGARDS recruited 30,239 US blacks (44%) and whites, aged 45 years or older in 2003 to 2007 who are being followed every 6 months for events. After excluding those with prior diagnosed stroke, this analysis involved 27,348 people. Participants reported their frequency of moderate-vigorous intensity PA at baseline according to three categories: none (physical inactivity), 1-3 times/week and ≥ 4 times/week. Stroke and TIA cases were identified and adjudicated during an average of 5.7 years of follow-up. Cox proportional hazards models were constructed to examine whether self-reported PA was associated with the risk of incident stroke. Results: Physical inactivity was reported by 33% of participants and was associated with a hazard ratio (HR) of 1.20 ([95% confidence intervals 1.02-1.42], p = 0.035). Adjustment for demographics (age, race, sex) and socioeconomic factors did not affect the HR, but further adjustment for traditional stroke risk factors (diabetes, hypertension, body mass index, alcohol use and smoking) completely attenuated this risk (HR 1.14 [0.95-1.37], p = 0.17). We examined the HR separately for men and women and found no significant association between PA frequency and risk of stroke although there was a trend towards increased risk for men reporting PA 0-3 times a week compared to 4 or more times a week. Conclusions: Self-reported low PA frequency is associated with increased risk of incident stroke. Any effect of PA is likely to be mediated through reduction of traditional risk factors such as hypertension, body mass index and diabetes.