12-month prevalence and concomitants of DSM-IV depression and anxiety disorders in two violence-prone cities in Brazil.

Background: Estimating 12-month prevalence of depression, anxiety, and comorbid anxiety/depression in noninstitutionalized adults (age 15-75) in two violence-prone cities.

Methods: The Composite International Diagnostic Interview v2.1 (Portuguese), administered in population-representative surveys (age 15-75) in São Paulo (N = 2536) and Rio de Janeiro (N = 1208), yielded 12-month prevalence of violent events experienced, and DSM-IV diagnoses of depression and anxiety, which were classified into mutually exclusive groups: 1) no anxiety/depression; 2) anxiety only; 3) depression only; 4) comorbid anxiety/depression. Weighted analyses estimated 12-month prevalence, multinomial logistic regression compared the demographic characteristics of the diagnosis groups, and association with experienced violence.

Results: Twelve-month prevalence of anxiety alone, depression alone, and comorbid anxiety/depression was 12.7% (of whom 24.9% were also depressed), 4.9% (of whom 46.2% had anxiety), and 4.2% respectively for São Paulo; and 12.1% (18.2% of whom were depressed), 4.6% (37.0% with anxiety), and 2.7% respectively for Rio de Janeiro. All conditions were approximately twice as prevalent in women than in men in both cities. In São Paulo, comorbidity was associated with age under 60, depression alone was more prevalent among 30-59 year olds, but in 23-29 year-olds in Rio de Janeiro. Exposure to violence increased the odds of anxiety, depression, and their comorbidity. With rare exception, marital status, education, and race/ethnicity were not associated with anxiety, depression, or their comorbidity.

Limitations: Cross-sectional design.

Conclusions: Prevalence rates for all conditions were high, and particularly associated with exposure to violence. Means to ameliorate violence, and its mental health effects, particularly for women, are needed.