Circulating irisin level in chronic kidney disease patients: a systematic review and meta-analysis.

BACKGROUND Irisin is not only a myokine but also an adipokine that is critical in many diseases including in the development of such diseases as obesity, diabetes mellitus, metabolic syndrome, coronary artery disease, and chronic inflammation. However, the association between irisin and chronic kidney disease (CKD) is unclear. This systematic review aimed to assess circulating irisin levels in patients with CKD and compare them with those in non-CKD patients. METHODS PubMed, EMBASE, CENTRAL, ISI Web of Science, and CNKI were searched to identify observational studies of circulating irisin levels in patients with CKD. Two reviewers independently searched the databases and screened studies according to the inclusion criteria. Data were extracted using a standardized collection form. Meta-analysis was performed to compare the differences in circulating irisin levels between CKD and non-CKD patients. RESULTS A total of 9 studies (6 cross-sectional and 3 case controls) involving 859 CKD patients and 393 non-CKD individuals were selected. The pooled data indicated that circulating irisin concentrations were significantly lower in CKD nondialysis patients (WMD = - 84.79, 95% CI - 170.23, 0.50; p < 0.05), peritoneal dialysis patients (WMD = - 235.81, 95% CI - 421.99, - 49.62; p = 0.01), and hemodialysis patients (WMD = - 217.46, 95% CI - 381.35, - 53.57; p = 0.009) than in healthy controls. CONCLUSIONS This study confirmed that irisin levels were decreased in patients with CKD. Moreover, circulating irisin levels were lower in dialysis patients than in nondialysis patients.