Randomized Placebo Control Study of Metformin in Psoriasis Patients with Metabolic Syndrome (Systemic Treatment Cohort)

BACKGROUND: Psoriasis has been found to be associated with obesity, metabolic syndrome (MS), diabetes, and cardiovascular risk factors. Metformin treatment showed improvement in cardiovascular risk factors and hyperinsulinemia. OBJECTIVE: To evaluate the efficacy and safety of metformin in psoriasis patients with MS. MATERIALS AND METHODS: This was a single-center, parallel-group, randomized, open-label study with blinded end point assessment of metformin (1000 mg once daily for 12 weeks; n = 20) and placebo (n = 18) in psoriasis patients with MS. Total sample size was 38 participants. RESULTS: Statistically significant improvement was observed in mean percentage change in erythema, scaling, and induration (ESI) (P = 0.048) in metformin as compared to placebo while mean percentage change in psoriasis area and severity index (PASI) and physician global assessment (PGA) scores was not significant (PASI – P = 0.215, PGA – P = 0.070). There was a statistically significant difference in percentage of parameters of MS improved following 12 weeks of treatment in metformin (19%) as compared to placebo (8.9%) group (P = 0.046). Statistically significant difference in percentage of patients achieving 75% reduction in ESI scores (P = 0.024). Significant improvement was observed in mean weight, body mass index (BMI), total cholesterol, and low-density lipoprotein (LDL) cholesterol in metformin group as compared to placebo. Improvement in BMI, fasting plasma glucose, serum triglycerides, high-density lipoprotein, LDL, systolic blood pressure, diastolic blood pressure, and total cholesterol was statistically significant in metformin group over the period of 12 weeks. There was no significant difference in adverse events in two groups except weight gain. CONCLUSION: Metformin has shown improvement in psoriasis and parameters of MS, hence can be used for the benefit of psoriasis patients having MS. Large, controlled studies are needed to confirm.