Circulating neutrophil gelatinase-associated lipocalin and gestational diabetes mellitus: a meta-analysis

Background: Many studies have assessed the role of circulating neutrophil gelatinase-associated lipocalin (NGAL) on the risk of gestational diabetes mellitus (GDM), but the results remain uncertain. Thus, this study aimed to assess the association between NGAL and GDM risk by performing a meta-analysis. Methods: We carried out a systematic search of electronic databases (PubMed, Embase, Wanfang and Chinese National Knowledge Infrastructure databases) to retrieve all related studies. The estimates of standardized mean difference (SMD) and its 95% confidence interval (CI) were calculated in a random-effects model. Between-study heterogeneity was assessed using I2. Results: Of all included 17 studies, 1080 pregnant women with GDM and 1736 controls were finally included in our analysis. The overall estimate indicated that circulating NGAL levels were higher in the GDM cases comparing to normal pregnant women (SMD: 3.16; 95% CI: 2.28, 4.04; p < 0.001). In stratified analyses, larger differences were observed in women with maternal age <30 years compared to those with maternal age ≥30 years (SMD 4.23 vs. 1.30), and among studies with BMI not matched compared to BMI matched studies (SMD: 4.29 vs. 2.63), but no difference was observed in Caucasian population (SMD: 1.68; 95% CI: –0.68, 3.99; p = 0.157). Conclusion: Our findings show that elevated levels of circulating NGAL might be more likely to be found among GDM women. Circulating NGAL might be a helpful detecting marker for the judgment of the occurrence of GDM. Nevertheless, further prospective studies are needed to assess this potential role.