Circulating von Willebrand Factor Levels in Patients with Prediabetes

Objective: Impaired glucose tolerance (IGT) is a well established risk factor for cardiovascular diseases. However there is not clear evidence to show that the same is true for impaired fasting glucose (IFG). von Willebrand factor (vWF) is an important marker for endothelial dysfunction. The vWF levels are elevated in all well known risk factors for cardiovascular diseases. The aim of this study is to search for any elevation of vWF levels in subjects with IFG and IGT and to compare them with the levels of the healthy volunteers. Material and Methods: Ninety five pre-diabetics diabetics without any confounders; IFG (n=47, mean age=46.55 +/- 6.6, M/F=28/19), IGT (n=48, mean an age=47.3 +/- 6.9, M/F=28/20) and 58 healthy volunteers (mean age=44.5 +/- 9.8; F/M=25/33), matched for age, body mass index and gender were enrolled. Morning venous samples were collected after 12 hours of fasting. Fasting blood glucose, insulin, lipid and vWF levels were studied. Insulin resistance state was estimated by using HOMA test. Results: All groups were similar in terms of age, body mass index and gender. The FPG (p<0.001), insulin (p=0.003), Homeostasis Model Assesment (HOMA) (p<0.001), triglycerides (p=0.003) and vWF levels (p=0.03) were significantly higher when compared to those of the control subjects. No significant difference was observed regarding the above parameters in subjects with IFG and IGT. Conclusion: The high vWF levels in subjects with IFG imply the presence of endothelial dysfunction even in the very early stage of preb-diabetes. Regarding that there was no significant difference between IFG and IGT, it concluded that endothelial dysfunction is present even in patients with IFG. In conclusion, IFG should not be undervalued as a cardiovascular risk factor.