Adiponectin levels in patients with psoriasis: a meta-analysis

Conflicting results regarding adiponectin levels in patients with psoriasis have been reported. We carried out a meta-analysis on studies which compared adiponectin levels of psoriatic patients with controls. A published work search was performed through PubMed (MEDLINE), EMBASE and the Cochrane Library for articles published in English. Pooled standardized mean difference (SMD) and 95% confidence intervals (95% CI) were calculated by using random effects and fixed effect models. Heterogeneity between studies was assessed using the Cochran's Q and I(2) statistics. A total of nine studies were enrolled (389 cases and 360 controls) for adiponectin, and three studies were included (132 cases and 132 controls) for high-molecular weight (HMW) adiponectin. Adiponectin and HMW adiponectin levels were not significantly different in patients with psoriasis compared with controls (SMD, -0.151 [95% CI, -0.616 to 0.315]; P = 0.526 for adiponectin; SMD, 0.999 [95% CI, -2.626 to 4.624]; P = 0.589 for HMW adiponectin). The associations were borderline significantly different in the stratum of those with a mean age of less than 40 years (SMD, -0.516 [95% CI: -1.032 to 0]; P = 0.050). Sensitivity analyses were not substantially altered in the direction of effect when any one study was excluded. No publication bias was detected. The level of adiponectin and HMW adiponectin may not be associated with psoriasis. The relationship between psoriasis and adipokines needs more in-depth studies with larger sample sizes.