The role of microalbuminuria and insulin resistance as significant risk factors for white matter lesions in Japanese type 2 diabetic patients

Objective: The presence of white matter lesions (WML) is an important prognostic factor for the development of stroke. Microalbuminuria, which is associated with diabetes, has been flagged as a novel predictor for cerebrovascular events. This preliminary study was therefore designed to test the hypothesis that the presence of WML correlates with microalbuminuria and insulin resistance in patients with type 2 diabetic mellitus (DM) not receiving insulin treatment. Patients and methods: Based on brain magnetic resonance imaging (MRI) findings, 90 type 2 diabetic patients were divided into two groups: a WML-positive group (57 +/- 8 years, mean +/- SD, n = 34) and a WML-negative group (57 6 years, n = 56). The level of blood glucose was assessed by fasting plasma glucose (FPG), fasting immunoreactive insulin (F-IRI), homeostasis model assessment (HOMA) index, and hemoglobin A(1c) (HbA1c). Results: The body mass index was higher in the WML-positive group than in the WML-negative group (p < 0.01). Plasma levels of triglycerides were higher while high-density lipoprotein cholesterol (HDL-C) was lower in the WML-positive group than in the WML-negative group (p < 0.05 and p < 0.0001, respectively). Fasting plasma glucose (p < 0.005), insulin concentrations (p < 0.0001), HOMA index (p < 0.0001), and urinary albumin excretion (p < 0.0001) levels were higher in the WML-positive group than in the WML-negative group. Multivariate logistic analysis revealed that WML was independently predicted by the microalbuminuria and insulin resistance (p < 0.005, p < 0.0005, respectively). Conclusion: The results of this preliminary study indicate that the presence of WML was associated with the microalbuminuria and insulin resistance in these Japanese patients with type 2 DM; larger cohort studies are warranted to confirm these findings.