Supplementary Material for: The relationship between vascular aging phenotypes and renal damage among individuals with type 2 diabetes

Objective: To investigate the relationship between vascular aging (VA) phenotypes and renal damage in type 2 diabetic population. Methods: In this cross-sectional study, we included 8,141 individuals with type 2 diabetes who participated in the Kailuan Study during 2010 to 2018 and completed the brachial-ankle pulse wave velocity (baPWV) assessment for arterial stiffness, an indicator for VA. The age- and sex-specific 10th and 90th percentiles of baPWV based on a reference cohort were used as cutoffs to define supernormal VA (SUPERNOVA, baPWV<10th percentiles), normal VA (NVA, baPWV 10th to 90th percentiles), and early VA (EVA, baPWV>90th percentiles). The estimated glomerular filtration rate (eGFR) and proteinuria levels were used to assess renal damage, including isolated proteinuria, isolated kidney function decline (eGFR<60ml/min/1.73m2), and proteinuria combined with kidney function decline. Multivariable logistic regression analysis was used to analyze the relationship between VA phenotypes and diabetic kidney damage. Results: The prevalence of isolated proteinuria, isolated kidney function decline, and proteinuria combined with kidney function decline was 17.0%, 12.2%, and 5.4%, respectively. Compared with NVA, SUPERNOVA was associated with 34% lower odds (95% confidence interval [CI]: 0.46-0.96) of isolated proteinuria after adjusting for age, sex, and other potential confounders. EVA was associated with higher odds of all three types of kidney damage; the adjusted odds ratio (95% CI) was 1.42 (1.20-1.67) for proteinuria, 1.24 (1.01-1.51) for kidney function decline, and 1.56 (1.18-2.06) for proteinuria combined with kidney function decline. Conclusions: Vascular aging phenotypes are associated with renal damage, especially isolated proteinuria. SUPERNOVA was associated with lower odds of isolated proteinuria and EVA was associated with higher odds of proteinuria and kidney function decline.