Apolipoprotein E Polymorphism and the Progression of Diabetic Nephropathy in Type 2 Diabetes

Background/Aims: Three different apo E alleles (E2, E3 and E4) produce apo E isoproteins, which regulate the metabolism of lipoproteins. This study investigated the apo E polymorphisms as a prognostic factor for the development of diabetic nephropathy (DN). Methods: A total of 525 type 2 diabetic patients were enrolled to participate in this prospective observational study. Apo E gene polymorphisms were analyzed by polymerase chain reaction. The progression of DN was defined as a shift to a higher stage of DN or a doubling of the baseline serum creatinine level by the end of the study. Results: The mean follow-up period was 42.4 months. The patients whose DN progressed had significantly higher urine albumin/creatinine ratios and fewer used diuretics than those in whom DN did not progress. In the Cox regression analysis, the apo E4 carriers were found to be at greater risk of progression of DN than non-apo E4 carriers (p = 0.007, hazard ratio 2.252). After adjusting for confounding factors, apo E4 carriers remained at increased risk of progression to more severe DN (p = 0.002, hazard ratio 2.820). Conclusion: Our study suggests the apo E4 carrier might serve as a predictor of DN progression in Taiwan. Copyright (C) 2011 S. Karger AG, Basel