Lack of association between CAG repeat polymorphism in the androgen receptor gene and the outcome of rheumatoid arthritis treatment with leflunomide

PURPOSE: Leflunomide (LEF) is a disease-modifying antirheumatic drug used for treating rheumatoid arthritis (RA) and the action of which may be modified by sex hormones. The aim of this study was to examine the association between CAG repeat polymorphism in the androgen receptor (AR) gene and the response to treatment with LEF in women with RA. METHODS: We studied 114 women diagnosed with RA and treated with LEF (20 mg daily). Follow-up was 12 months. CAG repeat polymorphism was determined using polymerase chain reaction (PCR) and subsequent fragment analysis by capillary electrophoresis. RESULTS: Analysis revealed no statistically significant associations between CAG repeat polymorphism in the AR gene and improvement of disease activity parameters: erythrocyte sedimentation rate, serum C-reactive protein, patient’s global assessment of disease activity on a visual analog scale (VAS), disease activity score of 28 joints (DAS28), and swollen and tender joint count. CONCLUSION: Our results suggest no correlation between CAG repeat polymorphism in the AR gene and response to treatment with LEF in women with RA.