If your fibromyalgia symptoms started gradually (as opposed to a sudden onset), you may have been able to deal with them during the early years. But women with fibromyalgia often notice a worsening of symptoms in their late 30s to early 40s with the onset of peri-menopausal hot flashes, night sweats, sleep disruption, daytime fatigue, and mood fluctuations.

As estrogen levels start to decline in peri-menopause and hit rock bottom in menopause, this triggers symptoms that could go untreated and might make your fibromyalgia worse. For example, the sleep complaints are very bothersome for peri-menopausal women, yet sleep studies have failed to find evidence of disturbed sleep when comparing pre-, peri-, and post-menopausal women. But what about comparing peri-menopausal women who have significant symptoms to those with very minimal symptoms? This was the basis for a research study presented at the annual SLEEP conference in San Antonio, TX, June 6-9, 2010.¹

The study was very small, comparing only six women in the symptomatic group to six in the mild symptom group (i.e., controls), but here are a few of the trends that the University of Melbourne researchers identified:

• Women in the symptomatic group had higher daytime sleepiness compared to the controls. Two validated questionnaires were used and both showed that symptomatic women are very sleepy.
• Symptomatic women spent less time in bed than controls … the difference was almost an hour.
• Women with lots of symptoms received less deep-level (stages 3 and 4) sleep compared to the controls. This difference was not highly significant and may go unnoticed by most sleep labs because when the overall sleep efficiency was calculated for the two groups, the results were the same.
• The sleep in symptomatic women may not feel as refreshing or restorative as it used to be because this group of women has less parasympathetic nervous system activity during sleep. Remember, the parasympathetic system is responsible for “rest and digest” functions that should dominate during nighttime sleep. Unfortunately, this system’s activity is not normally measured during a standard sleep study (e.g., it is mostly used for research).

A much larger study involving 35 post-menopausal women who were estrogen deficient (i.e., not on hormone replacement) was presented at the same conference and the findings expand upon those in the previous study.² The average age of the women was 54 and here is what the overnight polysomnographic measurements revealed:

• Average time to fall asleep was 25 minutes and the time spent awake after having fallen asleep was 52 minutes.
• The average number of arousals during the night was 50, which helps explain why much time is spent awake.
• The women obtained an average of only 10 minutes a night of deep-level (stage 3 and 4) sleep. This value should be closer to 45 minutes, so post-menopausal women without estrogen are truly missing out on the restorative phase of sleep. It’s also the stage of sleep that causes the release of growth hormone for repairing the tissues so this hormone may be significantly less as well.
• The calculated sleep efficiency for the group of women was 85 percent. This is the cut-off for being scored as “normal” by most sleep centers and shows how deceiving this value can be.

If your sleep is unrefreshing, whether you are an estrogen deficient women experiencing menopausal symptoms or you are a person with fibromyalgia, a sleep study could be helpful. However, make certain that the sleep center pays special attention to the time spent in deep-level sleep and the number of arousals. The sleep efficiency of fibromyalgia patients is often graded as normal, but the actual components of your sleep could be greatly disturbed.

1. Baker F, et al. SLEEP Volume 33, Abstract 074 A28 Supplement 2010.
2. Davis E, et al. SLEEP Volume 33, Abstract 619 A208 Supplement 2010.