For reasons researchers are still trying to understand, clinical depression appears to be almost twice as common in women as in men. Why females are more prone to this debilitating disease than their male counterparts is still under investigation, although significant progress has been made.
For reasons researchers are still trying to understand, clinical depression appears to be almost twice as common in women as in men. Statistics show that approximately 24% of women suffer a major depressive episode at some point in their lives, compared with 15% of men (Hirschfeld et al., 1997).
According to a consensus panel sponsored by the National Depressive and Manic Depressive Association (NDMDA), whose results appeared in the Jan. 22/29, 1997 issue of JAMA, depression is one of the most prevalent of all medical illnesses in both men and women. It is associated with long duration of episodes, high rates of chronicity, relapse and recurrence, psychosocial and physical impairment, and mortality and morbidity, with a 15% risk of death from suicide in patients who have ever been hospitalized for depression.
Despite these facts, the panel noted that the vast majority of patients with chronic depression are misdiagnosed, receive inappropriate or inadequate treatment, or are given no treatment at all.
Why females are more prone to this debilitating disease than their male counterparts is still under investigation, although significant progress has been made.
Depression is a common and costly mental illness that affects approximately 17.6 million Americans each year (National Institute of Mental Health D/ART Online Information, 1998). Yet of all people who are depressed, only 10% will get the treatment they need (Robins and Regier, 1991).
According to a 1996 National Mental Health Association (NMHA) survey, only one out of three women who experience clinical depression will ever seek care, and women experience increased depression between the ages of 25 and 44 (Weissman, 1984).
Research data indicate that people suffering from depression have imbalances in the activity of the neurotransmitters in the brain. Two neurotransmitters implicated in depression are serotonin and norepinephrine. Scientists believe a deficiency in serotonin may cause the sleep problems, irritability and anxiety associated with depression. They also believe a decreased amount of norepinephrine, which regulates alertness and arousal, may contribute to the fatigue and depressed mood of the illness (American Psychiatric Association Online Public Information, 1997).
In 1997, investigators at McGill University used new imaging techniques to measure serotonin secreted in the brains of eight healthy men and seven healthy women. The results of the study showed that as a group, the men produced 52% more of the neurotransmitter than did the women. These findings, which appeared in the May 13, 1997 issue of the Proceedings of the National Academy of Sciences, indicate a causal link between depression and serotonin activity (Nishizawa et al., 1997).
To date, there is insufficient evidence to indicate that natural menopause causes depression (Nichol-Smith, 1995). Among postmenopausal women who suffer depression, psychosocial factors appear to be the main predictors of depression. These include a past history of depression, socioeconomic status, stressful life events such as the death of a loved one, and negative beliefs about menopause. Various studies have found no direct correlation between estrogen levels and depression.
There is also inconclusive evidence that hormone replacement therapy improves depression in women who seek help for menopausal problems (Hunter, 1996). Such therapy is used to alleviate hot flashes, night sweats and other vasomotor symptoms that accompany menopause in some women.
Family studies suggest genetic factors may contribute to the development of a depressive disorder. Studies of identical twins have shown that if one twin has depression, the other has a 70% to 80% chance of suffering from depression. The incidence among nonidentical twins, other siblings and parents is 25%. Studies including first- and second-degree relatives of both biological and adopting families of depressed individuals found a concentration of depressive disorders three times greater among biological relatives than among adopting families (National Institute of Mental Health, 1994).
By contrast, childhood environment appeared not to contribute to depression. In a study published in the November 1994 issue of American Journal of Psychiatry, despite the large number of people studied and the variety of family relationships, there was no evidence that parents, neighborhoods or schools caused adults to report symptoms of depression (Kendler et al., 1994).
Among the several implications psychosocial influences have for depression is the still-nebulous area of women's role in society and the anxiety that the role engenders. Studies indicate that individuals with certain characteristics-pessimistic thinking, low self-esteem, a sense of having little control over life events and proneness to excessive worrying-are more likely to develop depression. These attributes may heighten the stressful events or interfere with taking action to cope with them. Some experts have suggested that the traditional upbringing of girls might foster these traits and that they factor in the higher rate of depression (National Institute of Mental Health D/ART Online Public Information, 1998).
During the teen-age years, studies have shown that girls in high school are more likely than boys to experience depression. In addition, girls are also more likely to have an anxiety and/or eating disorder than males.
Adult relationships also play a role in depression. For both women and men, depression is more common among those who are separated and divorced than among people who are married. However, rates of depression are highest among women who are unhappily married. Widowhood is frequently accompanied by depression. Adult sexual or physical abuse, as well as child abuse, are also associated with a greater risk of depression (National Institute of Mental Health, 1995).
One of the most important findings from the NDMDA-sponsored consensus panel was that individuals with depression are being seriously undertreated, even though effective treatments have been available for more than 35 years.
In light of the prevalence and pernicious nature of depression, the economic cost of the illness, its treatability, and previous public and professional educational efforts, the panel questioned why many people with depression were receiving inadequate treatment or getting no treatment at all.
The researchers reported: "There is still an enormous gap between our knowledge about the correct diagnosis and treatment of depression and the actual treatment that is being received in this country. Reasons for the gap have been attributed to patient, provider and health system factors. Patient-based reasons include: failure to recognize the symptoms, underestimating the severity of depression, limited access to treatment, reluctance to see a mental health care specialist due to stigma, noncompliance with prescribed medical regimens and lack of adequate insurance reimbursement."
The factors attributed to physicians, the panel noted, include failure of medical schools in providing sufficient education about psychiatric diagnosis, limited provider training in interpersonal skills, belief in the myth that psychiatric disorders are not "real" illnesses, inadequate time to evaluate and treat depression, failure to consider psychotherapeutic approaches, avoidance of treating patients with depression because of poor insurance coverage, poor collaboration among providers, prescribing inadequate doses of antidepressant medication for inadequate durations, and the fact that psychiatric disorders may take more time to diagnose and treat than many other medical conditions.
What Physicians Can Do
To improve the quality of services to depressed patients, the panel proposed educating patients to act as informed consumers and advocates; developing performance standards for behavioral health care; removing barriers to provider recognition, diagnosis and screening through educational programs; encouraging collaboration among primary care physicians, psychiatrists and other mental health professionals; and conducting research on the development and testing of new treatments.
In regard to effectively treating women for depression, the NMHA informs physicians to be aware that more than half of the women surveyed in their recent study believe it is "normal" for a woman to be depressed during menopause; believe depression is a normal part of aging and cite embarrassment or shame as barriers to treatment.
American Psychiatric Association Online Public Information (1997), Depression. Available at
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Kendler KS, Walters EE, Truett KR et al. (1994), Sources of individual differences in depressive symptoms: analysis of two samples of twins and their families. Am J Psychiatry 51:1605-1614.
National Institute of Mental Health D/ART Online Public Information (1998), Depression Awareness, Recognition and Treatment. Available at
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National Institute of Mental Health (1994): Depressive Illness: Treatments Bring New Hope. NIH Publication No. 94-3612.
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