High BMI Plus Inactivity Increases Risk of Fibromyalgia
Obese women who exercise at greater risk than normal-weight women with similar activity level
THURSDAY, April 29 (HealthDay News) -- Overweight and obesity are associated with an increased risk of fibromyalgia in women, particularly in those who are physically inactive or exercise less than one hour per week, according to a study in the May issue of Arthritis Care & Research.
Paul J. Mork, Ph.D., of the Norwegian University of Science and Technology in Trondheim, and colleagues conducted a longitudinal study of an unselected population of 15,990 women who did not have physical impairments or fibromyalgia at baseline. Assessments of physical exercise and body mass index (BMI) were done at baseline, and follow-up lasted 11 years.
Fibromyalgia was reported in 380 women. The researchers found that the level of exercise was only weakly associated with risk of fibromyalgia (P = 0.13), with women reporting the highest level of exercise having a relative risk of 0.77; however, they found that BMI was an independent risk factor for fibromyalgia (P < 0.001). Compared with normal-weight women, those who were overweight or obese had a 60 to 70 percent greater risk of fibromyalgia. Overweight or obese women who exercised at least one hour per week had a relative risk of 1.72, compared with women who were normal weight and had a similar exercise level. However, the relative risk for obese or overweight women who exercised less than an hour per week was 2.19, and it was 2.09 for those who did not exercise at all.
"The current study shows that a high BMI (i.e., being overweight or obese) is a strong and independent risk factor for future development of fibromyalgia. Moreover, the higher relative risks for the combined effect of being overweight/obese and inactive, relative to being overweight/obese alone, point to a further disadvantage for overweight women who do not exercise," the authors write.