Correlation of 25-Hydroxycholecalciferol and Glycaemic Status in Recent Onset Type 2 Diabetes Mellitus

Abstract

Introduction: Type 2 Diabetes Mellitus (T2DM) is a non communicable disease caused by increased insulin resistance and beta cells dysfunction. Recently vitamin D has sparked wide spread interest in pathogenesis of diabetes by playing a role in insulin resistance. As a major regulator of homeostasis of calcium, vitamin D directly and/or indirectly improves insulin exocytosis and glucose tolerance. Aim: To estimate the serum 25 hydroxy cholecalciferol level and also to correlate with fasting, two hour postprandial blood glucose and Glycated Haemoglobin (HbA1c) values in recent onset T2DM patients. Materials and Methods: This cross-sectional study was conducted at Government Kilpauk Medical College, Tamil Nadu, India from November 2017-April 2018. One hundred and thirty nine recently diagnosed T2DM patients aged between 30-60 years of both sex, who were on oral hypoglycemic drugs for less than three months duration were included in the study. The patients were grouped into three groups according to their vitamin D levels, Group 1 Vitamin D deficient- 52 patients (≤20 ng/mL), Group 2- Insufficient Vitamin D -33 patients (>20-30 ng/mL), Group 3- Vitamin D sufficient-54 patients (>30 ng/mL). Fasting and 2 hour postprandial glucose, 25 hydroxy cholecalciferol and HbA1c were estimated. Statistical analysis was performed using analysis of variance (ANOVA) and Pearson’s correlation. Results: Out of 139 participants, 64 were males and 75 were females. The mean age of the study population was 50.64±5.343 years. The mean fasting blood glucose values among the three groups were 168.13, 129.61, and 125.33 mg/dL respectively. The mean two hour postprandial blood glucose values among the three groups were 269.44, 212.45, and 194.11 mg/dL respectively. The mean HbA1c among the three groups were 7.481±1.16, 6.027±0.31, and 5.86±0.19, respectively. Decreased 25 hydroxy cholecalciferol level in patients of T2DM showed a statistically significant inverse correlation with fasting and two hour postprandial blood glucose and HbA1c with p-value <0.001. Conclusion: The study suggested that hypovitaminosis D was prevalent in T2DM. The study showed that decreased vitamin D level in T2DM patients was associated with increased fasting, postprandial blood sugar, and HbA1c. So, vitamin D screening in diabetics and supplementation can improve the glycemic status.