Associations of Smoking, Physical Inactivity, Heavy Drinking, and Obesity with Quality-Adjusted Life Expectancy among US Adults with Depression

Abstract

Objectives: To examine associations between four health behaviors (smoking, physical inactivity, heavy alcohol drinking, and obesity) and three health indices (health-related quality of life, life expectancy, and quality-adjusted life expectancy (QALE)) among US adults with depression.

Methods: Data were obtained from the 2006, 2008, and 2010 Behavioral Risk Factor Surveillance System data. The EuroQol five-dimensional questionnaire (EQ-5D) health preference scores were estimated on the basis of extrapolations from the Centers for Disease Control and Prevention's healthy days measures. Depression scores were estimated using the eight-item Patient Health Questionnaire. Life expectancy estimates were obtained from US life tables, and QALE was estimated from a weighted combination of the EQ-5D scores and the life expectancy estimates. Outcomes were summarized by depression status for the four health behaviors (smoking, physical inactivity, heavy alcohol drinking, and obesity).

Results: For depressed adults, current smokers and the physically inactive had significantly lower EQ-5D scores (0.040 and 0.171, respectively), shorter life expectancy (12.9 and 10.8 years, respectively), and substantially less QALE (8.6 and 10.9 years, respectively). For nondepressed adults, estimated effects were similar but smaller. Heavy alcohol drinking among depressed adults, paradoxically, was associated with higher EQ-5D scores but shorter life expectancy. Obesity was strongly associated with lower EQ-5D scores but only weakly associated with shorter life expectancy.

Conclusions: Among depressed adults, physical inactivity and smoking were strongly associated with lower EQ-5D scores, life expectancy, and QALE, whereas obesity and heavy drinking were only weakly associated with these indices. These results suggest that reducing physical inactivity and smoking would improve health more among depressed adults.

Keywords: burden of illness; depression; quality-adjusted life-years; risk factors.