Serum Leptin, Resistin, and Adiponectin Concentrations in Psoriasis: A Meta-Analysis of Observational Studies

BACKGROUND: Psoriasis is an immune-mediated, inflammatory disease. Adipokines contribute to the regulation of immune-mediated processes and inflammation. OBJECTIVE: The aim of our study was to systematically review the literature for studies that have evaluated the circulating concentrations of adipokines in patients with psoriasis and controls and to meta-analyze the best evidence available. METHODS: Eligible were studies that have assessed leptin, resistin, or adiponectin concentrations in psoriatic patients and a reference group. The study was conducted in adherence with the PRISMA standards. RESULTS: Psoriatic patients had higher leptin concentrations compared to controls (random effects model, mean difference, MD = 5.64 ng/mL, 95% CI: 3.00-8.29, p < 0.0001). Heterogeneity among studies was high (I2 = 95.9%). Psoriatic patients had higher resistin concentrations compared to controls (MD = 4.66 ng/mL, 95% CI: 2.62-6.69, p < 0.0001). Heterogeneity was high (I2 = 99.2%). Finally, psoriatic patients had lower adiponectin concentrations compared to controls (MD = -1.87 μg/mL, 95% CI: -2.76 to -0.98, p