As the use of the continuous glucose monitoring (CGM) increased, the time in range (TIR) derived from CGM are now emerging as the core metric for clinical target and assessing diabetic complication beyond HbA1c. This study investigated the association between the CGM-derived TIR and microalbuminuria.
A total of 835 subjects with type 2 diabetes who underwent three-day CGM and urinary albumin-to-creatinine ratio were retrospectively reviewed. TIR was defined as the percentage of time spent within the glucose range of 70-180 mg/dL. Microalbuminuria was defined as albumin-to-creatinine ratio more than 30 mg/g.
Mean TIR of 3-day CGM data was 60.6 ± 25.9%. The overall prevalence of microalbuminuria was 40%. The prevalence of microalbuminuria decreased significantly with each TIR quartiles (Q1: 51.6%, Q2: 43.5%, Q3: 38.6%, Q4: 25.7%, p for trend < 0.001). Multiple logistic regression analysis revealed that the odds ratio of having microalbuminuria was 0.91 (95% CI: 0.86-0.98, p for trend = 0.005) per 10% increase in TIR after adjusting for multiple factors including use of ARB or ACE inhibitors. After further adjustment for glycemic variability (standard deviation and coefficient variation), the association between TIR and microalbuminuria still remained.
TIR is strongly associated with microalbuminuria in type 2 diabetes.