Combined Impact of Health Behaviors on Mortality in Low-Income Americans

African Americans and low-income whites have higher mortality than the U.S. general population. This study prospectively investigated the combined influence of major lifestyle factors and poverty on mortality in this vulnerable population.

Data were collected in 2002-2009 from 79,101 Southern Community Cohort Study participants, of which 67% were African American and 55% had household incomes <$15,000. Mortality outcomes were identified from the National Death Index though December 31, 2011 (data analyzed in 2014-2015). Healthy behavior scores were created based on tobacco smoking, alcohol intake, diet, physical activity, and sedentary time. The primary analysis was performed based on the score created by counting each participant as having met/not met public health guidelines for each behavior.

Healthy behavior scores were associated with reduced cancer, cardiovascular disease, and all-cause mortality. Associations were stronger for whites than African Americans: hazard ratios for all-cause mortality comparing participants meeting four or five guidelines versus participants meeting zero were 0.41 (95% CI=0.30, 0.55) for African American men; 0.36 (95% CI=0.24, 0.55) for white men; 0.46 (95% CI=0.36, 0.59) for African American women; and 0.27 (95% CI=0.18, 0.43) for white women. The association between healthy lifestyle and all-cause mortality was weaker among those with incomes <$15,000 than those with higher income, particularly in men (p<0.05 for interaction).

This study demonstrates the importance of health behaviors on mortality among all groups, but highlights the need for additional research to identify factors contributing to high risk of mortality among low-income and African American populations.