Does physical activity moderate the association between alcohol drinking and all-cause, cancer and cardiovascular diseases mortality? A pooled analysis of eight British population cohorts

OBJECTIVE: To examine whether physical activity (PA) moderates the association between alcohol intake and all-cause mortality, cancer mortality and cardiovascular diseases (CVDs) mortality. DESIGN: Prospective study using 8 British population-based surveys, each linked to cause-specific mortality: Health Survey for England (1994, 1998, 1999, 2003, 2004 and 2006) and Scottish Health Survey (1998 and 2003). PARTICIPANTS: 36 370 men and women aged 40 years and over were included with a corresponding 5735 deaths and a mean of 353 049 person-years of follow-up. EXPOSURES: 6 sex-specific categories of alcohol intake (UK units/week) were defined: (1) never drunk; (2) ex-drinkers; (3) occasional drinkers; (4) within guidelines (<14 (women); <21 (men)); (5) hazardous (14-35 (women); 21-49 (men)) and (6) harmful (>35 (women) >49 (men)). PA was categorised as inactive (≤7 MET-hour/week), active at the lower (>7.5 MET-hour/week) and upper (>15 MET-hour/week) of recommended levels. MAIN OUTCOMES AND MEASURES: Cox proportional-hazard models were used to examine associations between alcohol consumption and all-cause, cancer and CVD mortality risk after adjusting for several confounders. Stratified analyses were performed to evaluate mortality risks within each PA stratum. RESULTS: We found a direct association between alcohol consumption and cancer mortality risk starting from drinking within guidelines (HR (95% CI) hazardous drinking: 1.40 (1.11 to 1.78)). Stratified analyses showed that the association between alcohol intake and mortality risk was attenuated (all-cause) or nearly nullified (cancer) among individuals who met the PA recommendations (HR (95% CI)). CONCLUSIONS: Meeting the current PA public health recommendations offsets some of the cancer and all-cause mortality risk associated with alcohol drinking.