Prevalence of chronic widespread pain and fibromyalgia syndrome: a Korean hospital-based study

This study was conducted to estimate the point prevalence of chronic widespread pain (CWP) and fibromyalgia syndrome (FMS) in a primary care center of a hospital in Korea. CWP was defined as pain lasting more than 3 months involving all the classified pain sites (axial, left and right, above and below waist). FMS was diagnosed by the American College of Rheumatology (ACR) criteria and also by clinical judgment of a physician. All 1,077 subjects were classified into three groups as no chronic pain (NCP), chronic regional pain (CRP), and CWP. CRP was defined as chronic pain with the exception of CWP. The point prevalence of CWP was 6.5% (95% confidence interval (CI) 0.2-12.8) and the point prevalence of FMS was 1.7% (95% CI 0.0-4.9) by ACR criteria and 2.3% (95% CI 0.0-6.1) by clinical judgment, respectively. We also analyzed the differential demographic characteristics among patients with NCP, CRP, and CWP. When compared to NCP, CWP was significantly associated with the female gender after adjusting for other variables (odds ratio 4.2; 95% CI 1.4-12.4, P = 0.009). Compared to NCP, CWP patients had lower levels of education (P = 0.018), a lower likelihood of a professional occupation (P = 0.014), infrequent alcohol intake (P = 0.014) and a lower proportion of current smokers (P = 0.003) based on a univariable analysis. In this Korean hospital-based study, CWP patients were common and had different demographic characteristics and life habits from NCP.