Insulin resistance and serum levels of adipokines in patients with systemic lupus erythematosus: a systematic review and meta-analysis

Background: We aimed to perform a systematic review and meta-analysis of studies assessing the homeostasis model assessment for insulin resistance (HOMA-IR) values, serum adiponectin, leptin and resistin levels in patients with systemic lupus erythematosus (SLE). Method: Online databases were searched on 31 March 2019 in order to identify studies comparing HOMA-IR, serum adiponectin, leptin and resistin levels between patients with SLE and controls. A random-effects model was adopted. Results: Fifty-six studies involving a total of 4460 patients with SLE were included. Patients with SLE had significantly higher HOMA-IR values (standardized mean difference (SMD)=0.425; 95% confidence interval (CI) 0.156–0.693; I²=93.8%) than the control group. The serum levels of adiponectin (SMD=0.547; 95% CI 0.219–0.874; I²=90.1%), leptin (SMD=0.843; 95% CI 0.454–1.231; I²=94.4%) and resistin (SMD=0.856; 95% CI 0.199–1.513; I²=96.6%) were all higher among patients with SLE than controls. A meta-regression analysis revealed that the serum resistin level was positively correlated with disease activity (coefficient 0.123; 95% CI 0.051–0.195; p<0.001). Conclusion: Patients with SLE have higher HOMA-IR values and serum levels of adiponectin, leptin and resistin than individuals without SLE. The serum level of resistin correlates with SLE disease activity.