A population study of Hispanics in Puerto Rico with fibromyalgia (FM) found that those who were overweight and obese experienced more severe manifestations of FM-related symptoms, particularly memory impairment and urinary frequency. The study, “Clinical Manifestations Associated with Overweight/Obesity in Puerto Ricans with Fibromyalgia Syndrome,” was published in the Journal of Obesity.

Fibromyalgia patients are often overweight or obese, and obesity is associated with increased sensitivity to pain and an overall poorer health status, the authors noted. Insights into how increased weight enhances FM-associated manifestations, however, still lack supporting, detailed studies, although previous research has found obesity to be an independent risk factor for FM.

Researchers studied 144 adults with FM according to the American College of Rheumatology (ACR) classification criteria. Based on body mass index (BMI), patients were divided into two groups: non-overweight patients (BMI ≤ 24.9 kg/m2), and overweight and obese patients (BMI ≥ 25 kg/m2). This study did not distinguish between overweight and obese individuals due to the small number of patients, noting “overweight and obese patients were categorized into a single group, we were not able to assess differences in clinical manifestations between overweight FMS patients and obese patients separately. A larger sample size would be needed to perform such analysis.” The mean age of the patients was 50.2 years, 95.1 percent of them were women, and 75.7 percent overweight or obese.

After a static analysis, the researchers concluded that overweight and obese patients were more likely to have self-reported memory impairment, anxiety, shortness of breath, and urinary frequency than the other patients. In addition, the number points in the body that tend to be painful when pressed, known as tender points, was higher in the overweight and obese group. From previous studies, it was observed that obese patients have a higher perception of pain and this finding was confirmed by the authors in their report: “Obese patients were more likely to report pain after adjusting for age, gender, race, education level, and presence of health insurance. These findings could explain the association between BMI and pain perception in FMS.” Even when all variables were considered, researchers still found that memory impairment and urinary frequency differences remained significant in overweight and obese patients.

Despite the correlation between excess weight and FM symptoms found in this population with FMS, the authors concluded that further studies are needed to confirm these associations and to elucidate if weight reduction interventions could favorably impact the severity of FMS.