Urinary albumin : creatinine ratio predicts prediabetes progression to diabetes and reversal to normoglycemia: role of associated insulin resistance, inflammatory cytokines and low vitamin D.

BACKGROUND

The relationship between albumin : creatinine ratio (ACR), insulin resistance (IR), cytokines, dyslipidemia, and 25-hydroxy vitamin D (25-OHD) in individuals with prediabetes (IPD) was investigated to evaluate their role in predicting future risk of progression to diabetes.

METHODS

The aforementioned parameters were evaluated in 147 IPD with persistent impaired fasting glucose and/or impaired glucose tolerance over two oral glucose tolerance tests, who were then followed up at 3-monthly intervals for progression to diabetes or reversal to normoglycemia.

RESULTS

Data were analyzed for 137 IPD with at least 1-year follow-up. Forty-three IPD reversed to normoglycemia (Group I), 69 continued with prediabetes (Group II), and 25 progressed to diabetes (Group III) over a mean follow-up period of 28.36 ± 8.19 months. Baseline fasting blood glucose levels (BGLs), 2-h post-glucose BGLs, and ACR were lowest in Group I and highest in Group III. Of the 137 IPD, 54.75% (n = 75) had microalbuminuria. The IPD in the lowest ACR quartile had the highest reversal to normoglycemia. Cox regression revealed that baseline IL-6 was predictive of progression to diabetes (P = 0.03) and ACR was an independent predictor of reversal to normoglycemia (P = 0.007). Kaplan-Meier analysis showed higher reversal to normoglycemia in IPD without microalbuminuria (P < 0.001).

CONCLUSIONS

An increased ACR is associated with higher creatinine, IR, and cytokine levels and lower 25-OHD levels in IPD. Microalbuminuria is associated with decreased reversal to normoglycemia and increased progression to diabetes. Low 25-OHD may be associated with increased progression to diabetes, perhaps via modulation of the ACR.