When it comes to sleep, testosterone may be the somewhat forgotten hormone. We know a great deal about the importance of testosterone as the male sex hormone, its role in the body and the effects of testosterone deficits, particularly for men. But there's been relatively little attention paid to the effects of testosterone on sleep, for both men and women. A recent review of research seeks to bring some much-needed attention to the role that testosterone plays in sleep.
- The effects of sleep (and lack of sleep) on testosterone levels in men and women.
- The role that testosterone plays in obstructive sleep apnea and sleep-disordered breathing.
- The relationship between testosterone levels and sexual dysfunction, and how sleep may affect both.
Changes in testosterone levels occur naturally during sleep, both in men and women. Testosterone levels rise during sleep and decrease during waking hours. Research has shown that the highest levels of testosterone happen during REM sleep, the deep, restorative sleep that occurs mostly late in the nightly sleep cycle. Sleep disorders, including interrupted sleep and lack of sleep, reduces the amount of REM sleep and will frequently lead to low testosterone levels. And this is important for men and women.
There's strong evidence of a relationship between testosterone and sleep disordered breathing, including obstructive sleep apnea. Studies have shown that low testosterone levels frequently occur in men with obstructive sleep apnea. Men with obstructive sleep apnea are also more likely to suffer from complications to their sexual function, including low libido, erectile dysfunction and impotence.
- Men with erectile dysfunction were more than twice as likely to have obstructive sleep apnea as those without erectile dysfunction, according to one study. This study also showed that the more serious a man's erectile dysfunction, the more likely he was to also have obstructive sleep apnea.
- Another study showed that men with obstructive sleep apnea and erectile dysfunction also exhibited highly-fragmented sleep that reduced or eliminated their REM sleep.
Men are more likely than women to suffer from sleep apnea and sleep-disordered breathing -- though there is widespread belief that sleep apnea in women remains significantly under-diagnosed -- and testosterone deficiencies may play a role.
What does this mean for men suffering from sleep problems or problems with sexual function? It's time to explore the connection between the two. First off, guys, you've got to go to the doctor. Making the decision to consult a physician is the first important step, one that unfortunately can still be a difficult one for some men. Men who are struggling with issues related to sexual function should have their sleep evaluated by their physician. The good news is that treatments for obstructive sleep apnea -- particularly the CPAP -- are safe and effective. In some cases, hormone replacement therapy for conditions such as erectile dysfunction may be appropriate, independently or in conjunction with treatment for a sleep disorder.
What are the implications for women of low testosterone levels from lack of sleep? Women are particularly vulnerable to sleep problems related to hormone changes and deficiencies throughout their lives. We talk most frequently about estrogen and progesterone, the primary hormones involved in menstruation. But testosterone should be added to the list of hormonal factors to consider when thinking about hormone-related sleep problems in women.
Women, like men, are also likely to find their sexual lives negatively affected by obstructive sleep apnea. Several studies have found strong correlations between obstructive sleep apnea and sexual dysfunction in women. As obstructive sleep apnea grows worse, problems with sexual function -- including sensation and desire -- become more serious, according to this research. Women are particularly at risk for un-diagnosed sleep problems, including sleep-disordered breathing. Women who are experiencing problems with sexual function should have their sleep evaluated. This works in both directions: Women who are being treated for sleep problems -- particularly obstructive sleep apnea -- should work with their physician to assess the potential effect of their sleep disorder on their sexual health.
We know that sleep deprivation poses a greater risk of cardiovascular problems for women than for men. It's just possible that the resulting lower testosterone levels may have something to do with this. Testosterone has a protective effect on the heart, reducing inflammatory proteins that can cause heart damage.
The more we know about how testosterone affects sleep and sexual health in men and women, the better clinicians will be able to help restore healthy functioning to two critical aspects of our lives.
Michael J. Breus, PhD
The Sleep Doctor™
Everything you do, you do better with a good night's sleep™