Maurice Ohayon, MD, PhD, DSc, associate professor of psychiatry and behavioral sciences and director of sleep epidemiology at the Stanford University School of Medicine, recently sought to determine the factors that contribute to insomnia among these midlife women. Below is a snapshot of his research findings, which will appear in the July 26 issue of the Archives of Internal Medicine.

The question:
To what extent can hot flashes in midlife women be considered a cause of chronic insomnia?

The background:
Because hot flashes may occur during the night, their presence has been frequently associated with insomnia; however, many other factors can be responsible for insomnia. These include anxiety and depression, which often occur during menopause, and sleep apnea or other sleep disorders, which become more common with age.

The study:
Researchers conducted telephone interviews with 982 women, ages 35 to 65, about their sleep history, hot flashes and overall health status. Chronic insomnia was defined as having difficulty getting to sleep or staying asleep at least three nights a week for the past six months or more. Hot flashes were evaluated on their frequency, severity and daytime functioning. The results were controlled for the presence of variables generally associated with insomnia.

The findings:
The overall prevalence of hot flashes was 79 percent in perimenopausal women (having at least one menstrual cycle in the past 12 months) and 51 percent in postmenopausal women (no menstrual cycles in the past year) - figures that are consistent with those from previous studies. The prevalence of insomnia was 57 percent in perimenopausal women an
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Contact: Michelle Brandt
mbrandt@stanford.edu
Stanford University Medical Center
26-Jun-2006