Estimated insulin sensitivity predicts regression of albuminuria in Type 1 diabetes

Abstract

Aim: To test the hypothesis that greater baseline insulin sensitivity would predict regression of albuminuria over 6 years in adults with Type 1 diabetes.

Method: We enrolled 81 people aged 30-48 years with albuminuria at baseline in the present study and re-examined them 6 years later. Urinary albumin excretion rate was measured and albuminuria was defined as urinary albumin excretion rate ≥ 20 μg/min. Regression of albuminuria was defined as normoalbuminuria (urinary albumin excretion rate < 20 μg/min) at follow-up. Predictors of regression of albuminuria were examined in stepwise logistic regression. The variables age, diabetes duration, sex, serum uric acid, HbA1c , systolic blood pressure, LDL cholesterol, HDL cholesterol, BMI, baseline albumin excretion rate, estimated insulin sensitivity at baseline, change in estimated insulin sensitivity from baseline to follow-up and angiotensin-converting enzyme inhibitor/angiotensin receptor blocker use were considered for inclusion in the model.

Results: Estimated insulin sensitivity was significantly higher at both baseline (4.6 ± 1.2 vs 3.4 ± 1.7; P = 0.002) and follow-up (5.2 ± 1.9 vs. 3.5 ± 1.7; P < 0.0001) in people who had regression of albuminuria vs those who did not. HbA1c (odds ratio 0.4, 95% CI 0.2-0.8; P = 0.006), estimated insulin sensitivity (odds ratio 2.5, 95% CI 1.3-4.9; P = 0.006) at baseline and change in estimated insulin sensitivity from baseline to follow-up (odds ratio 2.7, 95% CI 1.4-5.3; P = 0.003) were independently associated with regression of albuminuria in a multivariable stepwise model.

Conclusions: In conclusion, over 6 years, higher baseline estimated insulin sensitivity and change in estimated insulin sensitivity independently predicted regression of albuminuria. Improving insulin sensitivity in people with Type 1 diabetes is a potential therapeutic target to increase rates of regression of albuminuria.