We examined whether selected circulatory diseases (heart disease, stroke, diabetes and hypertension) were associated with an increased risk of major depression in the Japanese community population. Face-to-face household surveys were carried out in 7 areas, and a total of 2,436 persons participated (overall response rate: 58.4%) from 2002 to 2004. The WHO Composite International Diagnostic Interview 3.0 was used to diagnose major depression according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, and additional interviews assessed the presence of circulatory diseases. Using data from a random subsample of the respondents (n = 832), we conducted Cox proportional hazards models to calculate hazard ratios for the onset of major depression with comorbid circulatory diseases as a time-dependent covariate. Heart attack was significantly associated with the onset of major depression (hazard ratio [HR], 7.51 [95% Confidential Interval (CI), 1.36-41.45]) after adjusting for sex, birth cohort, smoking, alcohol intake, and education. Heart disease (HR, 2.12 [95% CI, 0.79-5.70]), diabetes (HR, 2.36 [95% CI, 0.4213.34]) and hypertension (HR, 0.97 [95% CI, 0.37, 2.50]) were not significantly associated. There were no subjects who developed major depression after stroke. These results suggest that heart attack, and maybe also heart disease and diabetes, affect the onset of major depression. Copyright© 2008 by Okayama University Medical School.