The effects of folic acid on markers of endothelial function in patients with type 1 diabetes mellitus.

BACKGROUND Endothelial dysfunction is considered as a fundamental and also preventable factor in the progression of vascular complications among type 1 diabetic patient. It occurs before the clinical manifestation of the mentioned complications. The aim of this study was to evaluate the effects of folic acid on endothelial function by measurements of adhesion molecules and von Willebrand factor (vWF) in patients with type 1 diabetes in Isfahan, Iran. METHODS This double blind, placebo-controlled crossover trial included type 1 diabetic patients aged 5-20 years old. Selected patients were randomized into two groups of A and B to receive folic acid 5 mg daily or placebo for 8 weeks. After a 2-week washout period, patients in the two groups were swapped to receive placebo or folic acid, respectively, for another 8 weeks. Blood and urine samples were taken to evaluate glycosylated hemoglobin (HbAlc), folic acid, vWF, intracellular adhesion molecule (ICAM), vascular cell adhesion molecule (VCAM), and microalbuminuria levels. Results of these measurements were compared in the two groups before and after folic acid and placebo administrations. RESULTS Fifty five type 1 diabetic patients aged 12.1 +/- 3.4 years with diabetes duration of 3.9 +/- 2.1 years were enrolled. Mean of folic acid level in the two studied groups was increased significantly (10.1 +/- 3.8 vs. 21.2 +/- 1.1 in group A and 15.5 +/- 1.9 vs. 19.9 +/- 2.8 in group B, p < 0.05). Mean of VCAM and microalbuminuria was decreased significantly after folic acid administration in the two groups (p < 0.05). Mean of HbA1c, ICAM and vWF did not significantly change after folic acid administration in the two groups (p > 0.05). CONCLUSION Folic acid administration decreased the level of endothelial dysfunction measured by adhesion molecules, especially VCAM and microalbuminuria. However, it did not significantly affect vWF. Further studies with larger sample size and long-term administration of folic acid are necessary for making precise decisions in this field. Key words: endothelial function, Diabetes Mellitus, folic acid.