Effects of High-dose Vitamin E Supplementation on Markers of Cardiometabolic Risk and Oxidative Stress in Patients with Diabetic Nephropathy: a Randomized Double-blinded Controlled Trial.

Introduction: Patients with diabetic nephropathy (DN) may benefit from vitamin E's antilipid and antioxidant activities. This study aimed to evaluate the effects of high-dose vitamin E supplementation on markers of cardiometabolic risk and oxidative stress in patients with DN.

Materials And Methods: This randomized controlled trial was carried out on 54 patients with DN that were randomly divided into 2 groups to receive vitamin E supplement (800 IU/d) or placebo for 12 weeks. Fasting blood samples were obtained at baseline and after the 12-week intervention to determine markers of cardiometabolic risk and oxidative stress.

Results: Vitamin E supplementation, compared with the placebo, resulted in a significant reduction in serum total cholesterol (-14.3 ± 29.9 mg/dL versus -0.8 ± 13.1 mg/L, P = .03), low-density lipoprotein cholesterol (-16.4 ± 28.5 mg/dL versus 0.1 ± 17.2 mg/L, P = .01), and ratio of total cholesterol to high-density lipoprotein cholesterol ratio (-0.5 ± 0.7 versus 0.1 ± 0.5, P = .001), and a significant elevation in vitamin E levels (39.7 ± 12.4 nmol/mL versus -0.5 ± 1.3 nmol/mL, P < .001) and high-density lipoprotein cholesterol levels (1.4 ± 3.7 versus -2.1 ± 5.1 mg/L, P = .006). It also resulted in a significant elevation in plasma glutathione levels.

Conclusions: Our study demonstrated that high-dose vitamin E supplementation for 12 weeks had favorable effects on lipid profile and glutathione levels of patients with DN, except for triglycerides, very low-density lipoprotein cholesterol, nitric oxide, and total antioxidant capacity levels.