Epidemiology of chronic musculoskeletal pain.

Chronic widespread pain (CWP) due to musculoskeletal conditions is a major social burden. The case definition of CWP relies on pain, chronicity (more than 3 months' duration) and widespread distribution (both sides of the body including the axial skeleton). Health Interview Survey (HIS) and Health Examination Survey (HES) have been used to assess the frequency of CWP in the general population. Unfortunately, both techniques are poorly standardised, which hampers comparison of data pertaining to different populations and countries. A major effort in the European Union (EU) is the development of common strategies to investigate musculoskeletal pain through HIS. Issues to be addressed include: (1) loss of daily life functions due to pain; (2) pain duration and rhythm; (3) affected sites; and (4) type of pain. We know that musculoskeletal pain affects between 13.5% and 47% of the general population, with CWP prevalence varying between 11.4% and 24%. Risk factors for musculoskeletal pain include age, gender, smoking, low education, low physical activity, poor social interaction, low family income, depression, anxiety and sleep disorders, as well as performing manual work, being a recent immigrant, non-Caucasian and widowed, separated or divorced.