Background: This study evaluates the role of depression as a specific risk factor for hypertension.
Methods: This study analyzed the prospective data in the Baltimore Epidemiologic Catchment Area (ECA) Follow-up Study (n=1920), a longitudinal population-based study of mental illness in East Baltimore. Incident cases of hypertension as assessed by self-report (n=148) in 1993 were compared to the remaining cohort without hypertension (n=901) across three waves of ECA interviews (1981, 1982, 1993). Depression and related symptoms were measured at baseline (1981) by the Diagnostic Interview Schedule (DIS) and categorized as dysphoria, dysthymia, or major depressive episode (MDE) according to Diagnostic and Statistical Manual (DSM) III criteria.
Results: Individuals with a major depressive episode compared to those who reported never having dysphoria had a marginally significant increased risk for hypertension (Odds Ratio (OR)=2.16; 95% Confidence Interval (CI) (0.94,4.98)) after adjustment for age, gender, race, body mass index, Nam-Powers socioeconomic score, alcohol usage, smoking, exercise, diabetes status, and number of general medical visits. MDE reported to have begun more than a year before the baseline measurement was associated with an increased risk for incident hypertension (Adjusted OR=3.67, 95% CI (1.25,10.79).
Limitations: Potential misclassification of self-reported hypertension outcome.
Conclusions: Even though the data are based on self-report of hypertension, these findings suggest that depression may be an independent risk factor for hypertension particularly for those with recurrent episodes or a long term history of the disease.