Tophaceous joint disease strongly predicts hand function in patients with gout

Objectives. The functional impact of gout is poorly understood. The aim of this study was to determine predictors of hand function in gout. Methods. Twenty unselected patients with gout were recruited from rheumatology clinics. No patient had an acute gout flare at assessment. Participants were assessed for clinical characteristics of gout, including the site and number of tophi. Hand function was assessed by the Sollerman hand function test. Fingertip to palm (FTP) distance measurement, grip strength and the Disability Assessment of Shoulder and Hand (DASH) questionnaire scores were also recorded. Data were analysed by simple and multiple linear regression models. Results. The median Sollerman score was 75.5 (range 31-80). The median hand FTP distance was 2.91 (0.88-6.69) cm, grip strength was 31 (4-71) kg, and DASH score was 28.77 (0-76.47). Of the clinical characteristics measured, the number of joints of the hand with overlying tophi (hand tophus joint count) was the strongest single predictor of the Sollerman score (r(2) = 0.59), and also predicted the other measures of hand mobility and function. A multiple regression model including hand tophus joint count, sex, number of gout flares in the preceding 6 months, gout disease duration and hand tender joint count was a better predictor of the Sollerman score than hand tophus joint count alone (r(2) = 0.81, F-4,F-14 = 3.94,P = 0.024). Conclusions. Measures of chronic and poorly controlled disease predict hand function in patients with gout. In particular, tophaceous joint disease has a major impact on functional capacity in gout.