Uric acid and skeletal muscle status in females with rheumatoid arthritis

Aim. To study the association of uric acid (UA) levels with skeletal muscle mass, strength and physical performance in women with rheumatoid arthritis (RA).

Materials and methods. One hundred thirty women (median age 61 [53; 66] years) with confirmed RA who signed informed consent were examined. A clinical and laboratory examination was performed, including an assessment of muscle strength, physical performance. Dual-energy X-ray absorptiometry according to the “whole body” program was done.

Results. The median UA level was 262.8 [197.4; 310.5] μmol/l, the incidence of hyperuricemia was 9.2%. Positive correlations of UA with the total lean mass index (r=0.32; p<0.001), appendicular lean mass index (r=0.24; p=0.006) were established. These associations were confirmed in multiple linear regression analysis (b*=0.38; p<0.001 and b*=0.29; p<0.001, respectively). There was no association between the level of UA and RA parameters (duration of the disease, glucocorticoid intake, RF and ACCP seropositivity, ESR, CRP and DAS-28 index), as well as with muscle strength. A negative correlation between the level of UA and parameters of physical performance was found.

Conclusion. The frequency of hyperuricemia was 9.2% in women with RA. Multiple regression analysis confirmed an independent association between lean mass and UA level.