Joint associations of alcohol consumption and physical activity with all-cause and cardiovascular mortality
Individual associations of alcohol consumption and physical activity with cardiovascular disease are relatively established, but the joint associations are not clear. Therefore, the aim of this study was to examine prospectively the joint associations between alcohol consumption and physical activity with cardiovascular mortality (CVM) and all-cause mortality. Four population-based studies in the United Kingdom were included, the 1997 and 1998 Health Surveys for England and the 1998 and 2003 Scottish Health Surveys. In men and women, respectively, low physical activity was defined as 0.1 to 5 and 0.1 to 4 MET-hours/week and high physical activity as ≥5 and ≥4 MET-hours/week. Moderate or moderately high alcohol intake was defined as >0 to 35 and >0 to 21 units/week and high levels of alcohol intake as >35 and >21 units/week. In total, there were 17,410 adults without prevalent cardiovascular diseases and complete data on alcohol and physical activity (43% men, median age 55 years). During a median follow-up period of 9.7 years, 2,204 adults (12.7%) died, 638 (3.7%) with CVM. Cox proportional-hazards models were adjusted for potential confounders such as marital status, social class, education, ethnicity, and longstanding illness. In the joint associations analysis, low activity combined with high levels of alcohol (CVM: hazard ratio [HR] 1.95, 95% confidence interval [CI] 1.28 to 2.96, p = 0.002; all-cause mortality: HR 1.64, 95% CI 1.32 to 2.03, p <0.001) and low activity combined with no alcohol (CVM: HR 1.93, 95% CI 1.35 to 2.76, p <0.001; all-cause mortality: HR 1.50, 95% CI 1.24 to 1.81, p <0.001) were linked to the highest risk, compared with moderate drinking and higher levels of physical activity. Within each given alcohol group, low activity was linked to increased CVM risk (e.g., HR 1.48, 95% CI 1.08 to 2.03, p = 0.014, for the moderate drinking group), but in the presence of high physical activity, high alcohol intake was not linked to increased CVM risk (HR 1.32, 95% CI 0.52 to 3.34, p = 0.555). In conclusion, high levels of drinking and low physical activity appear to increase the risk for cardiovascular and all-cause mortality, although these data suggest that physical activity levels are more important.