IMPACT OF VITAMIN D DEFICIENCY ON GLYCEMIC CONTROL IN PATIENTS WITH TYPE 2 DIABETES MELLITUS
DOI:
https://doi.org/10.53350/Annalspakmed.1.8.17Keywords:
Vitamin D deficiency, Type 2 diabetes mellitus, Glycemic control, HbA1c, Insulin resistance, 25-hydroxyvitamin D, Punjab PakistanAbstract
Background: Vitamin D deficiency is increasingly recognized as an emerging metabolic risk factor in patients with type 2 diabetes mellitus. Its potential role in glucose regulation, insulin secretion, and insulin sensitivity has gained clinical relevance, particularly in regions where deficiency is widespread.
Objective: To evaluate the impact of vitamin D deficiency on glycemic control among individuals with type 2 diabetes mellitus attending tertiary care hospitals in Punjab, Pakistan.
Methods: This cross-sectional study was conducted from January 2024 to March 2025, including 160 adults diagnosed with type 2 diabetes mellitus. Participants were recruited from tertiary care hospitals across Punjab using consecutive sampling. Serum 25-hydroxyvitamin D, fasting blood glucose, HbA1c, fasting insulin, and HOMA-IR were measured. Vitamin D status was categorized as deficient, insufficient, or sufficient. Glycemic control was assessed according to HbA1c levels. Statistical analysis included ANOVA, chi-square tests, and Pearson correlation, with significance set at p < 0.05.
Results: Vitamin D deficiency was highly prevalent, affecting 64 percent of participants. Patients with deficiency exhibited significantly elevated fasting glucose and HbA1c compared with those with sufficient vitamin D levels. Mean fasting glucose was highest in the deficient group (173.2 ± 31.6 mg/dL), and mean HbA1c was highest among deficient participants (8.7 ± 1.0%). Poor glycemic control was observed in 76.5 percent of vitamin D-deficient patients versus 27.3 percent of vitamin D-sufficient participants. Serum 25-hydroxyvitamin D demonstrated a strong inverse correlation with both fasting glucose and HbA1c.
Conclusion: Vitamin D deficiency is strongly associated with poor glycemic control and increased insulin resistance in patients with type 2 diabetes mellitus. Routine assessment and correction of vitamin D levels may serve as an effective adjunct in improving metabolic outcomes.
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