Exploring Nocturnal Hot Flashes and Poor Sleep in Menopausal Women

In a study published in the American Journal of Obstetrics and Gynecology, most women said that nighttime hot flashes were the main reason they woke up during sleep. The research showed that when these hot flashes were reduced, the women slept better. They didn't wake up as much during the night and had more efficient sleep overall.

Hot flashes are common during menopause and most women who report having hot flashes experience them daily, according to the Mayo Clinic. On average, hot flash symptoms persist for more than seven years. Some women have them for more than 10 years.

These hot flashes are known to disturb women during their sleep in their middle years.

However, the study suggests there isn't much research available to prove exactly how much hot flashes interrupt sleep or if treatments for hot flashes can help improve sleep.

In the randomized, double-blinded, placebo-controlled trial, skin patches were reviewed to see how nitroglycerin (NTG) could help with hot flashes in women going through menopause. Researchers also wanted to explore how hot flashes are linked to sleep problems in this group of women.

Beginning with 529 women who were on average in their 50s, 141 were included in the study, which ran from July 2017 to December 2021. The women were split into two groups: one received the NTG patches, and the other received placebo patches for 12 weeks.

To monitor the efficacy of the patches, the women kept diaries for a week at the start, at 5 weeks and at 12 weeks. They noted every time they had a hot flash, especially if it woke them up at night. They also tracked their sleep using the Pittsburgh Sleep Quality Index (PSQI), which scores sleep from 0 (best) to 21 (worst). Scientists checked how often the women woke up at night and how well they slept overall.

The participants also filled out surveys about their age, race and other personal information. In addition, they recorded their habits such as smoking or drinking, and their height and weight to calculate their BMI. This information made it possible for scientists to determine if the NTG patches made a difference in sleep and hot flashes compared to the placebo.

It was found that participants had an average of 10.8 hot flashes per day, including 2.6 at night that woke them up.

In the beginning of the trial, 62.6% of these women reported waking up at least twice a night because of hot flashes.

Over 5 and 12 weeks, the number of hot flashes waking them up at night decreased for both groups in the study, with one group having 0.9 fewer episodes per night and the other having 1.0 fewer.

Sleep disruptions, measured by how much time they stayed awake after initially falling asleep, also decreased.

Results found that the average time awake after sleep onset reduced by 10.1 minutes in one group and 7.3 minutes in the other. Both groups showed improved sleep quality, but there were no significant differences between the groups.

Previous research has shown that nighttime hot flashes can affect the sleep quality of menopausal women, while this study looks deeper into how these hot flashes impact sleep on a night-by-night basis.

Researchers suggest future studies should explore how hot flashes and sleep quality are associated in middle-aged women.

They added that while hot flashes can disrupt sleep, poor sleep could make women more aware of hot flashes. For example, mood problems could worsen both hot flashes and sleep troubles, creating a cycle where each issue makes the other worse.