Women and Depression: New Treatments and Alternative Therapies
Depression Risk Factors
Nearly twice as many women as men experience depression, and scientists have only recently begun to understand the complex factors that contribute to this gender gap.
Family history: Research suggests that genetics accounts for one-third to one-half of the risk of developing depression. "If a parent or sibling has depression, you're two to four times more likely to develop it," says Charles Nemeroff, M.D., chairman of psychiatry and behavioral sciences at the Emory University School of Medicine, in Atlanta. Women may be more vulnerable because of sex-specific genes linked to depression. A recent study of 81 families with severe recurring depression identified four chromosome regions (areas where genes reside) that are associated more strongly with depression in women than men. More than 80 percent of the women in the study who inherited a particular form of a gene called CREB1 developed depression. "More and more we're finding that gender matters," says study author George S. Zubenko, M.D., professor of psychiatry at the University of Pittsburgh School of Medicine.
Body chemistry: Depression is related to a shortage of the neuro-transmitter serotonin, which acts as a messenger between brain cells and helps regulate mood. "Men may be somewhat protected because they produce about 52 percent more serotonin in their brains than women do," says Marianne Legato, M.D., founder and director of the Partnership for Gender-Specific Medicine at Columbia University, in New York City.
Women not only make less serotonin, they also experience fluctuations of estrogen and progesterone throughout their reproductive lives, which can then cause fluctuations in their stores of the neurotransmitter. Estrogen can work to block the action of a brain enzyme known as monoamine oxidase, which reduces serotonin production. Falloffs in estrogen, which can happen before a menstrual period, after childbirth, or during midlife as women approach menopause, may lead to a temporary serotonin deficit. While not every woman is affected by this ebb and flow, "it seems that some women's brains are much more sensitive to fluctuations," says Louann Brizendine, M.D., director of the Women's Mood and Hormone Clinic and professor of psychiatry at the University of California, San Francisco. And this hormonal flux may switch on an inherited vulnerability to depression in certain individuals.
"The menopausal transition appears to be a period of increased risk for some women, whether they've experienced a prior depression or not," says Peter Schmidt, M.D., a clinical researcher in the behavioral endocrinology branch at the National Institute of Mental Health. That's likely due to this life stage's sometimes-dramatic hormonal dips and surges. In fact, a four-year study of 436 women between the ages of 35 and 47 found that those in perimenopause whose cycles were longer or shorter than usual by seven days or more were 55 percent more likely to report feeling depressed compared with premenopausal women whose cycle fell in the typical 22- to 35-day range.
Social factors: Work and family roles, relationships, and stress are also typical triggers of depression, more so in women than men. "Women tend to base their self-image on the success of their relationships in a way that is less true for men," says Ellen Haller, M.D., director of the adult psychiatry clinic at the University of California, San Francisco. "So their happiness often depends on the happiness of others."
Women are also more inclined to have a ruminative thinking style that increases their risk for depression. In a study of 1,300 randomly selected men and women, Susan Nolen-Hoeksema, Ph.D., professor of psychology at Yale University, in New Haven, Connecticut, found that women were more apt to replay stressful events and conversations in their heads endlessly, fixating on possible negative consequences. Such over-thinkers were prone to more prolonged and severe bouts of depression.