Severity of fibromyalgia symptoms is associated with socioeconomic status and not obesity in Korean patients.

Several studies conducted in Western countries have shown that obese or overweight patients with fibromyalgia (FM) exhibit more severe symptoms than patients of normal weight. However, there has been no study on the relationship between obesity and FM symptom severity in Asian patients. In this study, we evaluated the association between obesity, and other related factors such as socioeconomic status (SES), and FM symptom severity in Korean patients.A total of 343 participants were enrolled in this prospective cohort study, which used a nationwide survey of FM patients who were followed on an annual basis. We investigated health-related quality of life (QoL) and associated factors, such as demographic characteristics, SES, and physical and psychological function. The FM patients were assessed using the following self-reported questionnaires: the Medical Outcomes Study Short-Form Health Survey, the Fibromyalgia Impact Questionnaire, the Brief Fatigue Inventory, the Beck Depression Inventory, the State-Trait Anxiety Inventory, the Self-Efficacy Scale, and the Social Support Scale.Of the 343 patients, 76 (22.1%) were obese; these patients did not differ from the non-obese patients in terms of tender points or self-reported questionnaire scores. FM patients with lower SES - as indexed by unemployment, lower income, and education levels - had more severe symptoms, and poorer QoL and function compared to those with higher SES.In contrast to Western patients, symptom severity in Korean FM patients is associated with SES, but not with obesity.