Meta-analysis of circulating adiponectin, leptin, and resistin levels in systemic sclerosis

We aimed to evaluate the relationship between circulating blood adipokine levels and systemic sclerosis (SSc).

We conducted a meta-analysis on serum/plasma adiponectin, leptin, or resistin levels in patients with SSc and controls, and performed a subgroup analysis based on ethnicity and/or disease type.

Eleven studies (511 patients with SSc and 341 controls) were included in the meta-analysis. Meta-analysis revealed that adiponectin levels were significantly lower in patients with SSc than in controls (standardized mean differences [SMD] = -0.638; 95 % confidence intervals [CI] = -1.154, -0.122; P = 0.015). Stratification by ethnicity showed a low adiponectin level associated with SSc in Caucasians (SMD = -0.439; 95 % CI = -1.092, -0.213; P = 0.187) and Asians (SMD = -1.006; 95 % CI = -2.031, -0.019; P = 0.055), although this result was not statistically significant. Stratification by disease type revealed that the adiponectin level was significantly lower in the diffuse SSc, but not limited SSc, group than in the control (diffuse: SMD = -1.445; 95 % CI = -2.276, -0.614; P = 0.001; limited: SMD = 0.188; 95 % CI = -0.064, 0.439; P = 0.144). Meta-analysis showed no association between leptin levels and SSc (SMD = -0.029; 95 % CI = -1.362, 1.304; P = 0.966), and no association between resistin levels and SSc (SMD = 0.202; 95 % CI = -0.091, 0.496; P = 0.177).

Our meta-analysis revealed a significantly lower circulating adiponectin level in patients with SSc than in controls. This difference was apparent in the diffuse type of SSc, but not in the limited type. However, circulating leptin and resistin levels were not different between patients with SSc and healthy controls.