Impact of treatment with methotrexate and TNF alpha inhibitors on insulin resistance in patients with psoriasis

Abstract

Objective: A strong link between psoriasis and obesity, type 2 diabetes, insulin resistance dyslipidaemia and metabolic syndrome has been documented. The aim of this study was to investigate the effects of methotrexate (MTX), a conventional antipsoriatic agent, and tumour necrosis factor (TNF)-alpha inhibitors (TNFi) on insulin resistance in patients with psoriasis. Material and Methods: Thirty-one patients with psoriasis treated with MTX and TNFi were prospectively evaluated. Seventeen patients received MTX, while 14 received the TNFi treatment. At the baseline and at week 12 values of serum C-reactive protein (CRP), the Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) and lipid parameters were evaluated. Results: The decrease in CRP levels after the treatment was significantly higher in the TNFi group than in the MTX group (-1.76 vs. -0.1, p = 0.005; respectively). The levels of serum glucose showed increases in both therapy groups, which was statistically significant in only TNFi group (p = 0.012). Although it was not statistically significant, increases in the HOMA-IR values were noted in MTX and TNFi therapy groups (0.26 ± 1.77 vs. 0.59±1.81, p = 0.558, p = 249; respectively). Conclusion: In the present study, a significant increase in the levels of fasting serum glucose was observed in TNFi group, and an increase in HOMA-IR values was noted in both therapy groups, which is not consistent with the literature. Despite the short follow-up period and small sample size, we believe that the effects of the TNFi and MTX demand caution for the follow-up of psoriasis, which is already an insulin-resistant condition.