According to the American College of Obstetricians and Gynecologists (ACOG), an estimated 6,000 U.S. women reach menopause daily. By 2020, the number of women over age 55 is estimated to be 46 million.1 With increasing life expectancy, many women will spend up to 40% of their lives in the postmenopausal stage.1 Studies of women going through the menopausal transition (both peri- and postmenopause) show a high prevalence of depressive symptoms, with some studies suggesting an estimate as high as 45%.2 Given the ever-increasing numbers of postmenopausal women in the United States, it is essential to find ways to address depression in this population.
Postmenopausal depression is likely caused by several intersecting factors, including hormonal changes, psychosocial stressors, and a previous history of mood disorders — although even women with no history of mood disorders can experience new-onset depression during the menopausal transition.3
During perimenopause, gonadal steroid hormones diminish. These hormones affect membrane permeability and also stimulate the synthesis of neurotransmitters and the expression of receptors associated with depression.4 In particular, estrogen can modulate neurotransmitter turnover, enhancing the levels of serotonin and noradrenaline (norepinephrine). It also is involved in the regulation of serotonin receptor number and function.5 Diminishing estrogen levels can lead to a reduction in the levels of these neurotransmitters and receptors and may be responsible for the depressive symptoms associated with menopause.4,6
It is known that exercise improves depressive symptoms in the general population and has been found effective in augmenting pharmacologic management in severe depression.7,8 Exercise significantly contributes to enhancing the health and quality of life in older adults9 and preventing the appearance of adverse symptoms and the development of disease among postmenopausal women.10,11 Exercise may also constitute a powerful tool in combating depression in this population.
To investigate this hypothesis, Villaverde Gutierrez and colleagues12 studied the impact of exercise on depression and anxiety in 60 postmenopausal women, aged 60 to 70 years. For a six-month period, subjects were randomized either to an exercise program (N=30) or to a no-intervention control group (N=30).