Evaluating obesity in Fibromyalgia Syndrome patients

A study conducted at the University of Utah Pain Management and Research Center has found that many patients with Fibromyalgia Syndrome are overweight or obese.

The aim of the study was to investigate the associations between obesity and Fibromyalgia Syndrome.

Thirty-eight patients with Fibromyalgia Syndrome were included in the study. Neuroendocrine factors (levels of: catecholamines, including the neurochemicals epinephrine, norepinephrine, and dopamine; cortisol; C-reactive protein [CRP], a measure of inflammation; and interleukin-6 [IL-6], a cytokine with many functions involved with immunology), symptom measures (as measured by the Fibromyalgia Impact Questionnaire), sleep factors (as measured by an Actigraph), and physical functioning (as measured by treadmill testing) were studied. Body mass index (BMI) provided the primary indicator of obesity.

The researchers found that approximately 50% of the patients were obese and an additional 21% were overweight.¹

Strong positive associations were found between BMI and levels of IL-6 and epinephrine, and somewhat weaker associations with cortisol and CRP. BMI was also related to maximal heart rate and inversely related to distance walked. BMI was associated with disturbed sleep: total sleep time and sleep efficiency. No associations between self-reported symptoms and BMI were found.

The researchers concluded that:

"This study provides preliminary evidence suggesting that obesity plays a role in [Fibromyalgia syndrome] related dysfunction."

However, there is a theory that the changes in the Central Nervous System that happen with Fibro could cause some of the results found in this study, and that these could contribute to obesity in Fibromyalgia Syndrome patients, rather than the other way round.

This study also makes no reference as to medications the patients may have been on - many medications recommended as treatments for Fibromyalgia Syndrome have weight gain as a side effect - nor is it clear whether other conditions may have been involved.

References:

1. Okifuji A, Bradshaw DH, Olson C. Evaluating obesity in fibromyalgia: neuroendocrine biomarkers, symptoms, and functions. Clin Rheumatol. 2009 Jan 27. [Epub ahead of print]