adulthood, but a first episode may occur in childhood, adolescence, or later years of adulthood. The postpartum period is a time of increased risk for new mothers, and some people experience recurrent depression associated with seasonal changes (seasonal affective disorder). Stressful life events or circumstances are also recognized as risk factors: death of a spouse or child, divorce or other marital disruptions, assault or abuse, social isolation, job loss or stress, and poverty (IOM, 1994). Community conditions, such as a poor economy or violence, can reinforce individual experience.
Depression may occur with or result from some medical conditions and other mental disorders, and some medications can produce depression. Use of tobacco and alcohol is more common among persons reporting depressed moods (Schoenborn and Horm, 1993), and substance abuse may produce symptoms of depression (Depression Guideline Panel, 1993a). Recurrence of depression, incomplete recovery between episodes, and previous suicide attempts are associated with increased risk for future depressive disorder (Depression Guideline Panel, 1993a).
Because 50 percent of those who experience one episode of depression have a second episode (Depression Guideline Panel, 1993a), primary prevention is an important goal. Particular personality traits or good social support may limit the impact of some risk factors. Overall, evidence for the effectiveness of primary prevention is not conclusive (IOM, 1994), but targeted prevention may have promise (e.g., Beardslee et al., 1993; Clarke et al., 1995). In addition, interventions in a variety of settings (e.g., schools, workplaces, homes, neighborhoods) have been shown to reduce depressive symptoms (Muñoz, 1993; IOM, 1994).
Once depression occurs, appropriate treatment can improve outcomes among people of all ages and can reduce the risk of relapse or recurrence (IOM, 1990; Depression Guideline Panel, 1993a; Sturm and Wells, 1995). Treatment with medication or psychotherapy is generally effective for depressive disorder, and other interventions (e.g., enhancing social support) can reduce depressive symptoms (Muñoz, 1993; IOM, 1994). Several factors may, however, hinder access to optimal treatment. Some people do not seek care or do not continue treatment to avoid the stigma still attached to mental health care. Lack of health insurance or limited coverage for mental health services may create financial constraints. Language and cultural barriers may also contribute (e.g., Padgett et al., 1994). In addition, many cases are not diagnosed or are not treated appropriately (Depression Guideline