Does hyperuricemia protect from rheumatoid inflammation? A clinical study.

The negative association between gout and rheumatoid arthritis is well accepted. The reason for this mutual exclusion is not clear; a protective immunosuppressive effect of hyperuricemia has been included among possible explanations. To test this hypothesis, we reviewed the charts of 160 rheumatoid arthritis patients on whom clinical information and followup for at least a year were available. We selected those patients with persistent hyperuricemia as defined by serum urate levels averaging above 7.5 mg% for at least 6 months. We found 12 patients fulfilling such criteria, and 11 of these were judged to have quiescent, minimally active, or inactive disease during hyperuricemic periods. In 2 patients, flares of the rheumatoid process coincided with normalization of serum urate levels. We propose that persistent hyperuricemia may protect against or decrease the expression of rheumatoid inflammation.