Background: Depression has a marked negative impact on geriatric patient mortality and morbidity. The risk factors and exact reasons for these effects are not well understood.
Method: Seeking to better define the factors, we retrospectively analyzed the effects of gender and age at onset of affective disorder in a naturalistic study of 192 geriatric patients consecutively admitted to a large midwestern tertiary care center between 1980 and 1987 for the treatment of unipolar depression.
Results: After controlling for age at index admission, patients with an onset of depression before age 40 suffered significantly (p < .05) less mortality in follow-up than those with onset after age 40. When effects of gender are examined, the effects of age at onset are most profound in women, with a threefold increase in the rate of death in the cohort with age at onset of depression after 70 years when compared to those with onset before age 40.
Conclusion: These results and those of others suggest that depressed elderly women with no previous history of affective disorder are at a markedly increased risk compared with elderly women with a history of affective illness for morbidity and mortality and that a significant proportion of elderly depressed patients are admitted to a psychiatric hospital for a depression that is secondary to serious medical illness.