April 3, 2006 -- Women approaching menopause are at increased risk for depression, and two new studies offer some of the strongest evidence yet that hormonal changes may be at least partially to blame.
Both studies followed women through the transition to menopause, known as perimenopause. None of the women had a history of depression prior to this time in their lives, but their risk of developing symptoms of depression greatly increased during these years.
The two studies are published in the April issue of the journal Archives of General Psychiatry.
The findings argue in favor of aggressive treatment of both menopausal symptoms and depression symptoms occurring during the transition to menopause, researchers say.
"There is a tendency to dismiss symptoms of depression as part and parcel of this transition, but they shouldn't be discounted," Massachusetts General Hospital researcher Lee S. Cohen, MD, tells WebMD.
"From a public health point of view, depression is a substantial illness with significant morbidity for patients and their families. This is a real problem, but the good news is that it is a problem that can be managed."
Risk of Depression
Cohen and colleagues followed 460 Boston women between the ages of 36 and 45 for up to six years. All of the women were premenopausal at enrollment, meaning that they still had regular periods or had not undergone other changes indicative of transition to menopause.
None of the 460 women had ever been diagnosed with major depression. But those who entered perimenopause during the study period were almost twice as likely as those who didn't to develop significant symptoms of depression.
The risk was greater in perimenopausal women who also had hot flashes, but it was still greatly elevated in those who did not have this and other common symptoms associated with transitioning to menopause, Cohen says.
Role of PMS and Smoking
In the second, similarly designed study, University of Pennsylvania School of Medicine researchers followed 231 women between the ages of 35 and 47 for eight years.
Once again, the women were premenopausal at entry and they had no prior history of major depression.
Blood samples were taken periodically throughout the eight-year period to determine hormone levels, and researchers also administered standardized tests designed to measure depression symptoms and clinical depression.
Compared to when she was premenopausal, a woman was more than four times as likely to have symptoms of depression during perimenopause. Changes in hormonal levels were significantly associated with the appearance of these symptoms, even after adjusting for other lifestyle factors that have been linked to depression.
A diagnosis of clinical depression was also found to be two-and-a-half times more likely during the transition to menopause.
"We are not saying that hormones are the only things that impact depression risk during this period of a woman's life," says researcher Ellen Freeman, PhD. "But both of these studies support the idea that hormones are directly involved."
Women in the study who reported more premenstrual syndrome (PMS) prior to the transition to menopause had an even greater depression risk than other perimenopausal women.
"We know that some women seem to have an increased sensitivity to hormone fluctuation," Freeman says.
Depression risk among smokers transitioning to menopause was also greater than for transitioning nonsmokers.
Hormone Therapy and SSRIs
Cohen points out that, as is the case with other menopausal symptoms, not all perimenopausal women will experience symptoms of depression.
"Most women do not develop major depression," he says. "But these findings do suggest that when (perimenopausal) women do develop symptoms of depression their family practitioner, internist, or ob-gyn should take this symptom seriously."
Hormone therapy, which is now used primarily for the short-term treatment of hot flashes and night sweats, has been shown in some studies to improve depression symptoms in women approaching menopause.
Treatment with antidepressants may also be appropriate, both researchers tell WebMD.
"For most women with no history of depression, these depression episodes are transient," Freeman says. "That doesn't mean that the available treatments shouldn't be tried. They definitely help a lot of women."