Abstract 9683: Leisure-time Physical Inactivity and Risk of Myocardial Infarction and All-cause Mortality: a Case-control Study
Background: Physical inactivity has pandemic qualities, with major impacts on cardiovascular morbidity and death. However, it is unclear whether the association is affected by extra-cardiac atherosclerotic disease (EAD) and in what ways physical inactivity before myocardial infarction (MI) affects post-MI prognosis. Our hypothesis is that leisure time physical inactivity (LTPI) is an important independent risk factor for MI, and that a sedentary lifestyle is associated with a less favorable outcome after MI.
Methods and results: The study included patients (n=734) with acute myocardial infarction (MI), and, for each patient, an age, gender, and city-of-residence matched control with no history of MI. Baseline physical activity level was compared between patients and controls and results were adjusted for medical history and clinical data including objective measures of EAD. All-cause mortality in both patients and controls during the course of the study was stratified according to level of physical activity: Leisure time physical inactivity was associated with a more than 2-fold risk of MI [unadjusted odds ratio (OR) 3.4, 95% confidence interval (CI) 2.59-4.45, P<0.001, adjusted OR 2.1, CI 1.45-2.91, P<0.001]. Survival at 6 years for LTPI vs. active patients was 70% vs. 90% (P<0.001) and for LTPI vs. active controls 81% vs. 95% (P=0.002). The unadjusted risk of death from all causes during follow-up was significantly higher in the LTPI group compared to the active group both for patients [hazard ratio (HR) 3.9, CI 2.57-6.01, P<0.001], and controls (unadjusted HR 3.3, CI 1.46-7.34, P=0.004). After adjustment the HR remained significantly elevated for patients (HR 2.3, CI 1.48-3.73, P<0.001) but not for controls (HR 1.7, CI 0.66-4.26, P=0.27).
Conclusion: Leisure time physical inactivity is independently associated with MI and death after MI.
- © 2013 by American Heart Association, Inc.