Aging, stress, and affective disorders.

The interaction between aging, stress, and affective disorders has interested researchers for many years. Many stressful events occur as a part of aging. The majority of elderly people seem to tolerate this fairly well, but constant uncontrollable stress can lead to changes in the functioning of the hypothalamic-pituitary-adrenal axis. There are also age-related changes in the sensitivity of the hypothalamic-pituitary-adrenal axis, which have little clinical effect on healthy subjects, but may be more significant in the presence of an affective disorder. Stress is a more important predictor of depression in the elderly than are genetic factors. Attempts to minimize stress and the stress response in the elderly may improve treatments of affective disorders in this population.