Association of Serum Vitamin D with Glycemic Control and Lipid Profile among Diabetic and Non-Diabetic Adults in Tertiary Care Hospitals of Dhaka, Bangladesh

Abstract

Background: Vitamin D deficiency has been increasingly associated with impaired glucose metabolism and metabolic abnormalities among patients with Type 2 Diabetes Mellitus. However, comparative data regarding serum vitamin D levels among diabetic and non-diabetic adults in Dhaka remain limited. Objective: This study aimed to evaluate the association of serum vitamin D levels with glycemic control and lipid profile among diabetic and non-diabetic adults attending tertiary care hospitals in Dhaka city. Methods: This comparative cross-sectional study was conducted from June 2025 to December 2025 among 200 adult participants, including 100 diabetic and 100 non-diabetic individuals attending tertiary care hospitals in Dhaka city. Sociodemographic and clinical data were collected using a structured questionnaire. Venous blood samples were collected following overnight fasting for estimation of serum 25-hydroxyvitamin D [25(OH)D], fasting blood glucose (FBG), HbA1c, and lipid profile parameters using standard laboratory procedures. Statistical analyses were performed using appropriate statistical software, and p-values <0.05 were considered statistically significant. Results: The mean serum vitamin D level was significantly lower among diabetic participants compared to non-diabetic controls (18.7 ± 6.5 ng/mL vs. 29.8 ± 8.3 ng/mL; p<0.001). Vitamin D deficiency was observed in 64% of diabetic participants and 22% of non-diabetic participants. Significant negative correlations were identified between serum vitamin D levels and fasting blood glucose (r = −0.482, p<0.001), HbA1c (r = −0.527, p<0.001), triglycerides (r = −0.446, p<0.001), LDL-C (r = −0.401, p=0.001), and BMI (r = −0.298, p=0.011). A positive correlation was observed between vitamin D and HDL-C levels (r = 0.314, p=0.007). Multivariate logistic regression analysis identified diabetes mellitus, elevated HbA1c, increased BMI, and reduced HDL-C as significant predictors of vitamin D deficiency. Conclusion: Serum vitamin D levels were significantly lower among diabetic adults and were associated with poor glycemic control and adverse lipid profile parameters. Routine monitoring of vitamin D status may be beneficial among diabetic patients for improved metabolic management.