Serum uric acid predicts changes in reports of non-gouty chronic pain: a prospective study among women with inflammatory and non-inflammatory pain.

Widespread pain has earlier been associated with an increase in serum urate (SU). The aim of this study was to longitudinally study the relation between changes in pain reporting and the level of SU among women with chronic pain. Consecutive female patients (n = 124; aged 20-70 years), at rheumatology and rehabilitation practices, with chronic musculoskeletal pain of different origins were followed for 1 year with repeated blood samples and questionnaires. Complete data were obtained from 107 individuals. Factors that predicted an increase in pain extension during 12 months were studied in a logistic regression model. Changes in SU showed a significant correlation (r = 0.36) with changes in the number of reported pain locations. An initially high SU level (OR = 4.46), frequent use of alcohol (OR = 1.32) and a high number of pain locations (OR = 1.24) independently predicted an increase in pain extension during 12 months, whereas the use of steroids (OR = 0.21) in patients with inflammatory disorders resulted in a decreased number of reported pain locations. A relative increase in SU in combination with report of a high number of pain locations turned out to be a risk factor of increased pain extension in a cohort of women with chronic non-gouty pain followed during 1 year. The importance of SU in relation to chronic pain and its prognosis needs to be validated in larger studies.