Yoga and aerobic exercise interventions may not significantly reduce sleep disturbances among midlife women experiencing hot flashes, according to a new study.
Researchers at University of Washington in the US said although the women had no difficulty falling asleep, disturbed sleep was common at baseline and remained after each intervention, with women in all groups waking during the night for an average of more than 50 minutes.
Previously published analyses of the same trial had found that the yoga and aerobic exercise interventions were associated with small but statistically significant improvements in subjective, self-reported sleep quality and insomnia severity.
"Our primary findings were that the two study interventions had no significant effects on objective sleep outcomes in midlife women with hot flashes," said Diana Taibi Buchanan, associate professor at the University of Washington.
"The main implication of this finding is that other behaviour treatments with the potential for effectively improving sleep in this population should be examined," said Buchanan.
The study involved 186 late transition and postmenopausal women with hot flashes who were between 40 and 62 years of age.
Study subjects had an average of 7.3 to 8 hot flashes per day. Participants were randomised to 12 weeks of yoga, supervised aerobic exercise, or usual activity.
Sleep measures were evaluated using wrist actigraphy, and bedtimes and rise times were determined primarily from the participants' sleep diaries.
Mean sleep duration at baseline and after each intervention was less than the seven or more hours of nightly sleep that is recommended by the American Academy of Sleep Medicine for optimal health in adults.
According to researchers, future study should explore other approaches for improving sleep quality in midlife women, such as cognitive behavioural therapy for insomnia.
The study was published in the Journal of Clinical Sleep Medicine.