Document Type : Original Article

Authors

Department of Endocrinology, Isfahan Endocrine and Metabolism Research Center, Isfahan University of Medical Sciences, Isfahan, Iran

Abstract

Objective: Type 2 diabetes mellitus (DM‑T2) is commonly associated with increased 
triglycerides (TG), low‑density lipoprotein cholesterol (LDL‑C) and low high‑density 
lipoprotein cholesterol (HDL‑C) levels. Fibrates like gemfibrozil are frequently used in 
diabetic patients to decrease TG and increase HDL‑C levels. We compared the efficacy of 
Vitamin C, an antioxidant vitamin, with gemfibrozil on serum HDL‑C in diabetic patients.
Methods: Type 2 diabetic patients, referred to our out‑patient clinic were randomly divided 
into three groups. After 1 month of lifestyle and diet modifications, groupsA, B, and C were 
prescribed 1000 mg Vitamin C, 600 mg gemfibrozil and combination of both, respectively. 
Before the study initiation and after 6th week of drug prescription, the blood samples were 
taken and analyzed for total cholesterol (Total‑C), HDL‑C, TG, fasting blood sugar (FBS), 
and hemoglobin A1c (HbA1c) levels.
Findings: Sixty‑seven patients entered, and 50 patients (18 male, 32 female) finished 
the study. Overall, serum HDL‑C increased significantly from 39.8 to 45.2 mg/dL in the 
participants (P = 0.001). HDL‑C increased 6.3, 4.4 and 5.0 mg/dL in groups A, B and C, 
respectively (related significances were 0.017, 0.022 and 0.033, respectively). Significant 
decrease of serum TG and Total‑C occurred in gemfibrozil and combination groups, 
but not in Vitamin C group. Changes in serum HDL‑C between three groups were 
not significant (P = 0.963). We found a significant decrease in TG and Total‑C in the 
groups B and C (P < 0.05), but no significant changes of TG, Total‑C, LDL‑C, FBS and HbA1c 
in group A (P > 0.05).
Conclusion: The results demonstrated that Vitamin C may have beneficial effects on HDL‑C 
in diabetic patients without significant effects on plasma glucose or other lipid parameters; 
however, its role for the treatment of low HDL‑C patients should be evaluated in larger 
studies.

Keywords

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