ROLE OF VITAMIN C ON GLYCEMIC CONTROL IN TYPE 2 DIABETES MELLITUS

Abstract

Background: Type 2 diabetes mellitus is a metabolic disorder characterized by hyperglycemia and is associated with long standing micro-vascular and macro-vascular complications. Despite the latest advancements in the treatment the disease progresses and has poor outcome ultimately. Pakistan is also affected by this disease. Normal glucose homeostasis is impaired leading to hyperglycemia as the primary defect is in insulin pathway. The chronic inflammation in type 2 diabetes mellitus yields free radicals which play significant role in the pathogenesis of disease. These free radicals impair the defense system and people with type 2 diabetes mellitus have fewer amounts of antioxidants to fight these radicals. Vitamin C is one of the important antioxidant that destroys these free radicals. Vitamin C can be obtained through dietary sources and in the form of supplements. When given in divided doses the vitamin C can reduce the oxidative damage. Objectives This study was conducted to see the effects of vitamin C on fasting blood sugar, glycosylated hemoglobin and random blood sugar. Materials and methods The sample size was calculated from the prevalence formula. The 159 sample size was calculated. Two groups were formed control group and treatment group. In order to equally distribute the patients in two groups a figure of 160 was chosen. The subjects were allocated randomly with the help of computer assisted balloting software. Those subjects who do not follow inclusion criteria were excluded. Vitamin C 500 mg twice daily for three months was prescribed to the treatment group along with oral hypoglycemic drugs. Every subject enrolled in the study was followed up after three months. At the baseline socio-demographic characteristics, anthropometric measurements and laboratory parameters which included baseline investigations (hemoglobin, lipid profile, renal profile, liver function tests) and glycemic parameters (fasting blood sugar, random blood sugar and HbA1c) were checked. After three months at the final follow up laboratory parameters were again checked. Vitamin C levels were checked for the 2 treatment group before the start of study and at the end of study. Data was analyzed on SPSS 23.0 and comparison between the groups and in between the treatment group was performed. The correlation was also checked between vitamin C and glycemic parameters (FBS, BSR and HbA1c). Results: Out of 160 type 2 diabetic patients 144 completed the study. FBS, BSR, HbA1c were significantly reduced for the treatment group (p < 0.001). Renal function tests (serum creatinine and serum urea) and hemoglobin were not statistically different between the groups and in between the treatment group. Liver function tests (ALT, AST and serum bilirubin) were not statistically significant between the control and treatment group however values between day 0 and day 90 in between the treatment group shows a p value of less than 0.05. The lipid profile also showed statistically significant result between the control and treatment groups and in between the treatment group. The vitamin was significantly (p < 0.001) negatively correlated with glycemic parameters (FBS, BSR and HbA1c). Vitamin C levels were lower before the start of study and showed statistically significant difference (p < 0.001) at the end of study in between the treatment group. Conclusion It can be concluded from the study that vitamin C levels are reduced in type 2 diabetes mellitus and by administration of vitamin C exogenously it can be beneficial for the patients as vitamin C lowers the fasting blood sugar, random blood sugar and HbA1c. Along with lowering of glycemic parameters it can be beneficial in reducing lipid peroxidation which is raised in type 2 diabetes mellitus