HbA1c variability and the development of microalbuminuria in type 2 diabetes: Tsukuba Kawai Diabetes Registry 2
Diabetologia - Clinical and Experimental Diabetes and Metabolism, 05/15/2012
Sugawara A et al. – HbA1c variability affects the development of microalbuminuria independently of mean HbA1c in type 2 diabetes. Further studies should be performed to evaluate the influence of HbA1c variability on other complications and in individuals of other ethnicities with type 2 diabetes.Methods
- HbA1c level was measured in 812 serially registered normoalbuminuric adults aged 21–79 years with type 2 diabetes.
- After registration, a 1–year period to establish baseline values for mean HbA1c and HbA1c variability (measured as the intrapersonal SD of serially collected HbA1c) was decided upon.
- The association between HbA1c variability and the development of microalbuminuria was determined by Cox regression analysis after adjustment for other risk factors for microalbuminuria.
- Microalbuminuria occurred in 193 patients during the observation period of (mean ± SD) 4.3 ± 2.7 years.
- Even after adjustment for mean HbA1c, HbA1c variability was a significant predictor of microalbuminuria independently of the mean HbA1c; the HR for every 1% (95% CI) increase in mean HbA1c was 1.22 (1.06, 1.40) (p = 0.005), and that for HbA1c variability was 1.35 (1.05, 1.72) (p = 0.019).
- The effects of these two variables were quite similar when 1 SD was used; the HR for every 1 SD increase (95% CI) in HbA1c was 1.23 (1.07, 1.43) (p = 0.005), and that for HbA1c variability was 1.20 (1.03, 1.39) (p = 0.019).