Difficulty falling asleep and staying asleep increase as women go through menopause according to research by Rush University Medical Center. Waking up earlier than planned also increases through late perimenopause but decreases when women become postmenopausal. The study is published in the July 1 issue of the journal SLEEP.
"Sleep difficulties, especially problems staying asleep, are relatively prevalent concerns among women going through the menopausal transition," said Dr. Howard Kravitz, associate professor of psychiatry and preventive medicine at Rush University Medical Center and a principal investigator of the study. "Approximately 16% of postmenopausal women report having difficulty falling asleep and 41% report waking up frequently during the night."
Compared with other ethnic groups, Caucasian women were more likely to report difficulty staying asleep, while Hispanic women were less likely than other ethnic groups to wake several times during the night. Hispanic women were also significantly less likely to report waking early than other ethnic group. Compared with Hispanic, Caucasian, African American and Japanese women, Chinese women were more likely to report early morning awakening.
The study involved over 3,000 women aged 42-52 years and beginning menopausal transition at the time of their enrollment in the Study of Woman's Health Across the Nation (SWAN). Participants underwent annual assessments for up to seven years. At each visit, participants were asked about frequency of trouble falling asleep, waking up several times a night, and waking up earlier than planned and unable to fall asleep again. They were also asked about the frequency of vasomotor systems such as hot flashes, cold sweats, and night sweats. Transition status was determined using bleeding criteria.
Sleep changes can be attributed at least in part to changing hormone levels. The study found decreases in estradiol, the major form of estrogen in the body, were associated with trouble falling asleep and waking several times, and increases in follicle stimulating hormone (FSH), a reproductive hormone, associated with waking several times.
In naturally postmenopausal women, women who were on hormone therapy had less trouble falling asleep and waking several times during the night than naturally postmenopausal women not on hormone therapy. However, whether or not women were hormone users did not influence the effect of vasomotor systems or changing hormone levels on sleep symptoms.
"Although we found some evidence that hormonal therapy could benefit these menopausal sleep related symptoms, this was not a consistent finding across all groups compared, so the role for this particular treatment needs more study," said Kravitz.
Among the eight menopausal status categories, women who were surgically menopausal without current hormone therapy treatment were most likely to report trouble falling asleep and waking several times. Women who reported vasomotor symptoms on more days in the preceding two weeks also were more likely to report difficulty sleeping.
Source: Rush University
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