Women in their late thirties and forties who have trouble sleeping are more than three times more likely to suffer sleep problems during menopause than women who have an easier time getting shut-eye, according to a new study by researchers from the Perelman School of Medicine at the University of Pennsylvania. Only 25 percent of women who had reported no earlier sleep problems developed moderate or severe insomnia or other sleep disturbances during a 16-year period around menopause. What's more, the researchers say that these sleep woes did not appear to be caused by menopause itself, which may quell common fears about symptoms associated with this phase of life. The study, published in the journal Menopause, is among the first to document long-term sleep patterns in women in the years before, during and after menopause.
"Sleep problems are a major issue for women approaching mid-life, particularly for women who have moderate or severe sleeping problems before reaching menopause as they are likely to experience increased issues throughout the transition," says lead author, Ellen W. Freeman, PhD, research professor in the department of Obstetrics and Gynecology at the Perelman School of Medicine at the University of Pennsylvania. "A small subgroup of women with only mild sleep disturbance prior to menopause also experienced worsening sleep disturbance during the transition, but our results show that for the majority of women, menopause does not further exacerbate existing sleep problems or cause new ones."
The study assessed annually the sleep patterns of 255 women participating in the Penn Ovarian Aging Study who reached natural menopause during a 16-year period (1996-2012). At enrollment, all women were aged 35 to 48 years and premenopausal, with 28 percent reporting moderate-to-severe sleep disturbances, which is similar to the prevalence of insomnia symptoms among adults, and 56 percent reporting no sleep disturbances at all. Over the 16 year period, 82 percent of the sample experienced moderate-to-severe issues with sleep, while only 7 percent had no poor sleep.
The study also found that hot flashes are strongly associated with poor sleep as expected, but a large proportion of poor sleep in menopausal women occurred without hot flashes. The finding, Freeman says, indicates that sleep difficulties in the transition to menopause in generally healthy women should not automatically be imputed to ovarian decline.
"Our study raises the question of why a significant increase in poor sleep should surface for a group of women who experienced only mild sleep problems earlier, but not among women who had moderate or severe sleep problems," said Freeman. "This is an area for future study and many potential factors should be considered, such as hormone fluctuations or changes, stress, anxiety, relationships, life events and health problems."
Freeman added that clinicians should be alert to the strong possibility that poor sleep in women approaching menopause is not simply caused by menopause or hot flashes.
"Possible reasons for poor sleep instead may include health problems, anxiety, and stress," she said, advising that clinicians should ask patients whether they had problems sleeping before midlife as well as obtain information on the level and duration of earlier poor sleep patterns to devise the most effective treatments.
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