Efficacy of methotrexate and tumor necrosis factor inhibitors in Japanese patients with active psoriatic arthritis.

Objective: The aim of this study was to assess the efficacy of oral methotrexate and tumor necrosis factor inhibitors in Japanese patients with active psoriatic arthritis.

Methods: We retrospectively investigated 51 patients who fulfilled the ClASsification criteria for Psoriatic ARthritis (CASPAR) criteria for the efficacy of tumor necrosis factor inhibitors and methotrexate. We assessed the visual analog scale score, psoriasis area and severity index score, C-reactive protein-based disease activity score in 28 joints (DAS28), swollen joint count (0-66), tender joint count (0-68), health assessment questionnaire score, C-reactive protein level, erythrocyte sedimentation rate, and matrix metalloproteinase 3, at both baseline and week 24.

Results: Of the 51 patients, 34 were male and 17 were female, with a mean age of 50.3 ± 13.2 years. The duration of psoriasis to onset of arthritis was 10.2 ± 9.1 years. At week 24, in the group treated with the tumor necrosis factor inhibitor plus methotrexate, the tender joint count declined from 6.05 ± 5.84 to 0.43 ± 1.03, the swollen joint count declined from 6.42 ± 4.36 to 0.00 ± 0.00, and the DAS28 declined from 4.35 ± 0.82 to 2.04 ± 0.68. In the group treated with methotrexate alone, the tender joint count declined from 3.70 ± 1.76 to 0.60 ± 0.86, the swollen joint count declined from 5.26 ± 4.00 to 0.27 ± 0.70, and the DAS28 declined from 3.91 ± 0.82 to 1.94 ± 0.53. There were no significant differences in the mean reduction in clinical measurements between the two groups.

Conclusion: Our study demonstrated that methotrexate and tumor necrosis factor inhibitors are effective for the treatment of active psoriatic arthritis in Japanese patients.