In a previous article from a cross-sectional study of 737 men and 771 women (40-42 years old) in Norway, we found a higher mean serum uric acid in persons with than without chronic musculoskeletal complaints. Furthermore, the odds ratio for chronic complaints increased by increasing uric acid level. Persons with chronic complaints are heterogenous. The scope of the present study was to inquire whether a further breakdown of the material would shed more light upon our previous findings, and thereby contribute to the understanding of the pathogenesis of chronic complaints. Among persons with such complaints, we wished to characterize the ones with the highest serum uric acid. As possible explanatory factors we used the former fibromyalgia minor criteria and modulating factors, and the presence or absence of widespread complaints judged from the Nordic form body map. Persons with chronic widespread weather-dependent complaints had the highest values. The odds ratios for this subgroup increased by increasing uric acid level to a greater extent than reported in our previous article. Some hypotheses about possible action mecanism are put forward, and the relation to fibromyalgia are briefly discussed. Uric acid needs attention in future studies on chronic widespread musculoskeletal complaints.