Microvascular endothelial function is an independent predictor for albuminuria progression among Asians with type 2 diabetes - A prospective cohort study.

Objective: We aim to investigate whether microvascular endothelial dysfunction is an independent predictor for future albuminuria progression in T2DM cohort. Methods: A total of 1098 patients with T2DM were clinically assessed at baseline and 3.2-year follow-up. Progression was defined as transition from normoalbuminuria (ACR <30 mg/g) to microalbuminuria (ACR = 30-299 mg/g) or macroalbuminuria (ACR >300 mg/g), or microalbuminuria to macroalbuminuria. Microvascular endothelial vasodilation at baseline was quantified using LDF. The increase in perfusion in response to ACh and NaNP was calculated. Logistic regression model was used to estimate the OR for albuminuria progression. Results: Albuminuria progression occurred in 226 (20.6%) patients. Baseline ACh was significantly higher in nonprogression than progression group (80.0 +/- 53.2% vs 72.0 +/- 49.7%, P=.04). There is no significant difference in NaNP between the two groups (111.1 +/- 80.3% vs 121.1 +/- 87.4%, P = .12). After multivariable adjustment, 1-SD increase in ACh was marginally associated with albuminuria progression (OR = 0.87, 95% CI, 0.72-1.02, P = .08) in all patients. When stratified by baseline albuminuria, 1-SD increase in ACh was significantly associated with albuminuria progression in normoalbuminuria (OR = 0.76, 95% CI, 0.59-0.97, P = .03), but not in microalbuminuria patients (OR = 1.18, 95% CI, 0.81-1.70, P = .39). Conclusions: Impaired endothelial-dependent microvascular reactivity predicts the onset of albuminuria progression among T2DM patients with normoalbuminuria.