Thiazolidinediones for plaque psoriasis: a systematic review and meta-analysis

There is some evidence for the role of inflammation and insulin resistance in the pathophysiology of plaque psoriasis. Thiazolidinediones are antidiabetic drugs that act by improving insulin sensitivity and also possess anti-inflammatory effects. Evidence from in vitro, animal and human studies has accumulated suggesting that these drugs may be of use in psoriasis.

This systematic review and meta-analysis was performed to assess the efficacy of thiazolidinediones on psoriasis severity.

Randomised, open-label or single blind or double blind, published as well as unpublished, studies of thiazolidinedione administration compared with placebo, given to patients with plaque psoriasis for at least 8 weeks were considered for inclusion in this review. The primary outcomes were as follows: mean or mean percent change in Psoriasis Area and Severity Index (PASI) from baseline to end of treatment with pioglitazone, proportion of patients showing >75% improvement in PASI score, and proportion of patients showing >50% improvement in PASI score. Data analysis was done using Revman 5.

Twenty-seven relevant citations were identified. Two studies each for pioglitazone and rosiglitazone were included in the meta-analysis. There was a significantly greater mean decrease in PASI scores from baseline to end of treatment (-4.24 (95% CI -5.35 to -3.12)) in the pioglitazone group as compared to placebo. There was a non-significant improvement in PASI50/70 in the pooled analysis of rosiglitazone trials.

Pioglitazone appears to have efficacy for the treatment of psoriasis. The clinical significance of the effect and role in management of psoriasis deserve further study.