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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