Estrogen Treatment Restores Normal Sleep Patterns in Menopausal Women
March 17, 2000 (New York) -- Estrogen replacement therapy (ERT) appeared to bring sleep patterns closer to normal and improve sleep quality in a group of postmenopausal women, according to a report in the February issue of the American Journal of Obstetrics and Gynecology.
"Sleep disorders become more common in women as they progress past menopause. Women have more trouble falling asleep and staying asleep. When they do sleep, it has been documented that they spend less time in rapid eye movement (REM) sleep and, therefore, when they wake up, they report that they feel less rested," Suzanne Trupin, MD, tells WebMD. Trupin is a clinical professor of obstetrics and gynecology at the University of Illinois College of Medicine at Urbana.
"When we look at studies of estrogen on sleep in menopausal women, estrogen usually improves the quality of sleep, reduces time to fall asleep, and increases the amount of REM sleep. Sleep lab studies also indicate estrogen reduces the number of times a patient awakens and may improve cognitive function," says Trupin.
A recent study cowritten by Irina A. Antonijevic, MD, PhD, of the department of psychiatry at the Max Planck Institute of Psychiatry in Munich, Germany, used advanced technology available in a sleep laboratory to help clarify some of the subtle effects of estrogen on the electrical activity of the brain during various stages of sleep and wakefulness.
The authors used a device called an electroencephalogram (EEG) to record the electrical activity of the brain while a group of women on ERT slept. They then compared those EEG recordings to others taken while the women were sleeping and off ERT therapy.
The group comprised women ages 46 to 62 years old who had gone through menopause, either naturally or surgically, and had been postmenopausal for at least one year. Five of the women were on ERT before the study and had their ERT sleep evaluation first and the non-ERT evaluation two weeks after a washout period. The rest of the group had the non-ERT evaluation, then began ERT treatment, and had a second sleep evaluation during the last two days of estrogen treatment.
Patients were either already on a patch that delivers estrogen through the skin before the study began or were prescribed one. Patches were changed twice weekly and released daily doses of estrogen.
The study confirmed that ERT had subtle but specific effects on sleep. For instance, ERT significantly increased the amount of time patients had REM sleep and reduced the time spent awake from 20 to 12 minutes during the first two sleep cycles of the night. A sleep cycle is a period of non-REM sleep followed by a minimum of five minutes of REM sleep. A sleep cycle can last approximately 70 to 120 minutes and be repeated four to six times a night.