Multi-site pain and work ability among an industrial population.

BACKGROUND Multi-site pain is a common phenomenon among working-age people and it strongly increases work disability risk. Little is known about the impact of musculoskeletal pain on work ability. AIMS To investigate whether the number of musculoskeletal pain sites predicts future poor work ability. METHODS The study was conducted in 2005 and 2009 in a food processing company. A total of 734 workers participated in the study. The information on self-perceived work ability and musculoskeletal pain during the preceding week was obtained through a structured questionnaire distributed to employees. The risk of poor work ability at follow-up related to the number of pain sites at baseline was estimated with logistic regression. RESULTS The proportion of poor work ability increased in 4 years from 15 to 22%, parallel to the increase in the number of pain sites. Among those with 'non-poor' work ability at baseline, one-tenth reported their work ability to be poor after 4 years. The number of pain sites predicted poor work ability after 4 years of follow-up with a dose-response manner. Those with widespread pain had almost a 3-fold risk of developing poor work ability at follow-up. The associations were stronger for younger and white-collar workers. CONCLUSIONS The results of the present study indicate that multi-site musculoskeletal pain at baseline strongly predicts poor work ability after 4 years among industrial workers. Counting the number of concurrent pain sites may be a simple method of identifying workers with high risk of work disability in occupational health practice.