WEDNESDAY, Feb. 8 (HealthDay News) -- Obese people are not only at greater risk for fibromyalgia, they are likely to experience more severe symptoms of the condition, such as chronic pain, fatigue, sleep disturbance and mood disorders, according to a new study.

The findings suggest that weight-loss strategies should accompany treatment plans for overweight patients with fibromyalgia, a syndrome characterized by widespread musculoskeletal pain that mainly affects women and has no known cure, according to researchers from the Mayo Clinic.

"We see an association between body mass index with symptom severity and quality of life in patients with fibromyalgia," study author Dr. Terry Oh, of Mayo Clinic's department of physical medicine and rehabilitation, said in a news release from the clinic. "This was the first study to look at distinct groups of obese patients and determine how weight correlates with levels of symptoms and quality of life."

In conducting the study, the researchers examined the body mass index (BMI) -- a measurement that takes into account height and weight -- of 888 patients with fibromyalgia. A BMI score of 30 or greater is deemed obese, and about half of the patients were in that category. One-quarter of the participants were considered severely obese with a BMI score greater than 35.

The patients also answered questions about their fibromyalgia symptoms and ability to function in daily activities. Oh's team found that as patients' weight increased so did the severity of their symptoms. Meanwhile, their quality of life dropped.

Severely obese patients also reported experiencing much more pain than other patients, the investigators found.

The study, published in the February issue of Arthritis Care & Research, noted that the higher rate of obesity among people with fibromyalgia may be due to chronic pain and inactivity, resulting in poor quality of life and a rise in disability.

"BMI has already been singled out as an independent risk factor for fibromyalgia," Oh stated in the news release. "Our results underscore the importance of incorporating weight management strategies in treatment programs for fibromyalgia patients."

While the study uncovered an association between obesity and severity of fibromyalgia symptoms, it did not prove a cause-and-effect relationship.

More information

The U.S. National Library of Medicine has more about fibromyalgia.

-- Mary Elizabeth Dallas

SOURCE: Mayo Clinic, news release, Feb. 7, 2012

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