Association between depression and chronic diseases: results from a population-based study

OBJECTIVE: To assess the association between depression and chronic diseases in adults. METHODS: Population-based cross-sectional study with a sample of 1,720 adults aged 20 to 59 years conducted in the city of Florianopolis, southern Brazil, in 2009. Multistage sampling was used and census tracts were the primary sample unit. Subjects were interviewed at home, and reported being diagnosed with depression (outcome) and 11 other chronic diseases (exploratory variable) by a health provider. They were grouped into those with no chronic disease, one, and two or more diseases. Gender, age, marital status, income, physical activity, hospitalization and medical visits were confounders. Poisson regression analysis was used to estimate prevalence ratios and related 95% confidence intervals. RESULTS: The prevalence os depression was 16.2% (95% CI 14.3; 18.2). It was higher in women, older individuals, widowed or divorced, and poor ones. Those who reported no leisure-time physical activity and medical visits in the last two weeks, and who were hospitalized in the last year also showed higher prevalence of depression and chronic diseases. Even after adjustment for confounders the prevalence of depression was 1.44 (95% CI 1.09; 1.92) times higher among those reporting one chronic disease and 2.25 times higher among those reporting two or more diseases than among those with no diseases. CONCLUSIONS: The prevalence of depression is much higher among people with higher burden of chronic diseases. Health professionals, health services, and policy makers must target specific strategies to this group.