Time trends in mortality associated with depression: findings from the Stirling County study

Abstract

OBJECTIVE: to address the question of whether a mortality risk associated with depression in a 1952 representative sample of Stirling County adults changed in a new sample in 1970, and whether there was a change in associations with cigarette smoking and alcoholism. METHOD: sample members were interviewed about depression and cigarette smoking. General physicians were interviewed by psychiatrists regarding alcoholism. Information about death as of December 31, 1992, was provided by Statistics Canada. Proportional hazards models were fitted in the 2 samples to assess the mortality risks associated with depression among men and women during 20 years of follow-up, and additionally among men with heavy smoking and alcoholism. Specific causes of death were investigated. RESULTS: hazard ratios representing the association between depression and premature death among men were 2.6 (95% CI 1.4 to 4.9) and 2.8 (95% CI 1.5 to 5.1), respectively, in the 1952 and 1970 samples for the first 10 years of follow-up. Hazard ratios for women were 1.4 (95% CI 0.6 to 3.2) and 1.2 (95% CI 0.5 to 2.9). The risk associated with depression among men was independent of alcoholism and heavy smoking. Depression and alcoholism were significantly associated with death by external causes and circulatory disease; heavy smoking was significantly associated with malignant neoplasms. CONCLUSION: the mortality associated with depression did not change during the period from 1952 to 1970. Depressed men experienced a significant mortality risk that was not matched among depressed women and also was not due to alcoholism and heavy smoking.