Pre-impaired Fasting Glucose State Is A Risk Factr for Endothelial Dysfunction Flow-mediated Dilation Japan (FMD-J) Study

Background There is little information on the relationships of fasting blood glucose (FBG) including high normal blood glucose and impaired fasting glucose (IFG) with endothelial function. The purpose of this study was to evaluate the relationship between FBG level and flow-mediated vasodilation (FMD) in detail using a large sample size. Methods This study was a cross-sectional study. We measured FMD in 7265 subjects at 31 general hospitals. The subjects were divided into four groups based on FBG levels: <5.55 mmol/L, 5.55–6.05 mmol/L, 6.11–6.94 mmol/L, and ≥ 6.99 mmol/L or known type 2 diabetes. The subjects were also divided into six groups based on FBG levels: <5.00 mmol/L, 5.00-5.22 mmol/L, 5.27–5.50 mmol/L, 5.55–6.05 mmol/L, 6.11–6.94 mmol/L, and ≥ 6.99 mmol/L or known type 2 diabetes. Results FMD decreased in relation to increase in FBG level. There was a significant difference in FMD between the FBG of < 5.55 mmol/L group and the other three groups (6.7 ± 3.1% vs. 5.9 ± 2.8%, 5.7 ± 3.1%, and 5.1 ± 2.6%; p < 0.001, respectively). After adjustment for confounding factors, the odds of having the lowest quartile of FMD was significantly higher in the FBG of 5.27–5.50 mmol/L, 5.55–6.05 mmol/L, 6.11–6.94 mmol/L, and ≥ 6.99 mmol/L or known type 2 diabetes groups than in the FBG of < 5.00 mmol/L, group. Conclusions These findings suggest that FBG of 5.55–6.05 mmol/L and FBG of 6.11–6.94 mmol/L are similarly associated with endothelial dysfunction and that a pre-IFG state (FBG of 5.27–5.50 mmol/L) is also a risk for endothelial dysfunction compared with FBG of < 5.00 mmol/L. Clinical Trial Registry Information: http://www.umin.ac.jp (UMIN000012950, UMIN000012951, UMIN000012952, and UMIN000003409)