Supplementary Material for: Meta-Analysis of the Relationship between Abdominal Obesity and Diabetic Kidney Disease in Type 2 Diabetic Patients

Background and Objectives: The meta-analysis aimed to investigate the association of visceral fat area (VFA), waist circumference (WC), waist-hip ratio (WHR) and waist-height ratio (WHtR) with diabetic kidney disease (DKD) in type 2 diabetic patients. Methods: Included studies were searched from Pubmed, Embase, and the Cochrane Library before July 2020. We synthesized the pooled results of the above relationships by meta-analysis. Results: Fourteen cross-sectional studies were enrolled. The pooled results indicated there was a significant difference in continuous VFA, WC and WHR/WHtR between patients with DKD and those without DKD (standard mean difference, SMD, 0.24, 95% confidence interval, CI, 0.13–0.36, p = 0.000). For VFA, patients with DKD had higher VFA levels than those without DKD (SMD 0.27, 95% CI 0.03–0.50). In the WC subgroup, patients with DKD had higher WC levels than those without DKD (SMD 0.17, 95% CI 0.10–0.24); similarly, abdominal obesity (dichotomized WC) was significantly associated with an increase in the odds of DKD (expected shortfall, ES, 1.57, 95% CI 1.32–1.86). However, the association of continuous WHR/WHtR with DKD was not statistically significant (SMD 0.43, 95% CI –0.12 to 0.97), while we found this relationship was statistically significant when analyzed categorically (ES 1.58, 95% CI 1.22–2.06). Conclusion: In this meta-analysis, we found abdominal obesity parameters (continuous VFA, WC) were associated with increased odds of DKD, and type 2 diabetic patients with DKD were more likely to have abdominal obesity (categorized using WC or WHR/WHtR).