Chronic musculoskeletal pain: a multifactorial process

Sammanfattning: The aim was to study prevalence, assessment methods, and risk factors of chronic musculoskeletal pain, as well as effects on health status in a general population setting. A postal survey to a representative sample of 3928 subjects aged 20–74 years in 2 municipalities on the west coast of Sweden was followed by clinical examinations of selected subjects, and a three-year follow up survey to 2425 subjects who answered completely to the first. The prevalence of all chronic musculoskeletal pain was 34.5% (95% CI 32.3– 36.7%), and the prevalence of chronic widespread pain (CWP) was 11.4% (95% CI 10.1–12.6%). The prevalence of fibromyalgia was estimated at a maximum of 1.3% (95% CI 0.8–1.7%). The prevalence of RA, according to the modified 1987 ARA criteria, was 0.50% (95% CI 0.27–0.72%). At the three-year follow up, 16.4% with initial chronic regional pain (CRP) had developed CWP, compared to 2.2% of those with initially no chronic pain (NCP). The majority of subjects (56.9%) who primarily reported CWP remained in that group at follow up. Developing CWP from NCP or CRP was predicted by older age, having a family history of chronic pain, and having more than 6 painful body regions at the baseline survey three years before. A weekly/daily habit of drinking alcohol and having personal social support was protective. Persistence of CWP was predicted by being an immigrant and having more than 12 regions with pain at the baseline survey. Family history of chronic pain was predictive in women but not in men. Health status as measured with SF-36 discriminated at baseline between subjects with NCP, CRP, and CWP. Low scores on 6 of the 8 health concepts (excluding the two mostly associated to mental health) predicted the development of CRP from NCP, and low scores on all 8 health concepts predicted the development of CWP from CRP. This study has shown that social, psychological, physical, and lifestyle factors contribute to development and persistence of CWP.