By Lana Barhum

Fibromyalgia is remarkably more common in women than it is in men, but when it comes to feeling its effects, there is little difference between the sexes, according to results of a new study published in the journal Pain Research and Management.

Fibromyalgia is a poorly understood disorder characterized by deep tissue pain, fatigue, depression and insomnia. As many as 90 percent of fibromyalgia cases are diagnosed in women.

The Al-Andalus Project consisted of 405 fibromyalgia patients and 247 non-fibromyalgia participants from southern Spain, the vast majority of them women. A significant limitation of the study is that only 73 men participated.

The researchers followed the groups for two years to see if gender-specific symptoms in the fibromyalgia patients existed. Participants were evaluated in several ways, including pain, lifestyle impact, fatigue, sleep issues, mental and emotional health, and cognitive performance.

In the fibromyalgia group, the men showed better working memory than women, whereas sleep latency (the length of time that it takes to go from full wakefulness to the lightest non-REM sleep state) was lower in the female participants. In the non-fibromyalgia group, the male participants showed higher pain thresholds in some areas, but not in others. 

The researchers found that some symptoms, including pain, in fibromyalgia men were worse than their non-fibromyalgia male peers. They believe the findings show that fibromyalgia might affect men more severely than women in tender point tenderness, mental health, and sleep latency, which contradicts earlier research on gender differences.

“Previous research has shown that fibromyalgia men present more severe limitations in physical functioning, social functioning, and health perception. However, we failed to find these differences between fibromyalgia women and men in the present study. Our results are consistent with other studies finding no gender differences in clinical key features in fibromyalgia," they wrote. 

It does still seem that the worst fibromyalgia symptoms, especially pain, affect females more severely than they do males, but the Al-Andalus researchers do not feel that is unique to fibromyalgia. 

"In the general population, women usually present greater pain sensitivity and lower pain threshold than men, which is in agreement with the results found in the nonfibromyalgia group of the present study," they wrote, noting that there is a difference in the way genders perceive and handle pain.

"It has been speculated that both peripheral and central nervous systems pathways might be involved in pain experiences; however, the mechanism underlying gender differences in pain remains misunderstood."

While the findings of the Al-Andalus Project do not support any significant gender differences in fibromyalgia and only offer some indication that fibromyalgia might affect men more severely with some symptoms, the researchers believe there’s a need to further understand why men and women perceive fibromyalgia pain and symptoms differently.

"Our results, then, suggest that fibromyalgia pain might be aggravated in men and, consequently, there might be gender-specific pain mechanisms in fibromyalgia," they said.

The Al-Andalus researchers believe further studies are needed that look at male and female fibromyalgia patients separately

“Given the low sample size of our sample, our findings should be interpreted as preliminary and future studies with a larger sample size of men might confirm or contrast the cut-off scores suggested in the present study," they wrote.

Lana Barhum lives and works in northeast Ohio. She is a freelance medical writer, patient advocate, legal assistant, and mother. Having lived with rheumatoid arthritis and fibromyalgia since 2008, Lana uses her experiences to share expert advice on living successfully with chronic illness. She has written for several online health communities, including Alliance Health, Upwell, Mango Health, and The Mighty.

 To learn more about Lana, visit her website.