Association between serum vitamin D3 levels and left ventricular diastolic dysfunction in type 2 diabetes mellitus patients with controlled glycemia: A cross-sectional study

A BSTRACT Background: Type 2 diabetes mellitus (T2DM) is a prevalent metabolic disorder linked to cardiovascular complications, notably left ventricular diastolic dysfunction (LVDD). Emerging evidence suggests low serum vitamin D3 levels may contribute to LVDD, though this association is unclear in patients with well-controlled glycemia. Materials and Methods: A cross-sectional study involved 160 T2DM patients aged 40–75 years, with diabetes duration ≥5 years and HbA1c ≤7%. Serum 1,25-dihydroxyvitamin D3 levels were measured, and echocardiographic assessments evaluated LVDD, graded by E/A and E/e’ ratios. Vitamin D3 levels were classified as deficient (<20 ng/mL), insufficient (20–30 ng/mL), or sufficient (>30 ng/mL). Regression analysis adjusted for confounders like body mass index (BMI), diabetes duration, and lipid profile to explore the vitamin D3–LVDD relationship. Results: Participants had a mean age of 45.38 ± 9.91 years and a male-to-female ratio of 1.22:1. The mean vitamin D3 level was 20.43 ± 11.82 ng/mL, with 58% of LVDD patients showing deficiency. LVDD was observed in 61% of patients (42% Grade 1, 14% Grade 2, 5% Grade 3). A significant negative correlation existed between vitamin D3 levels and LVDD severity ( P = 0.018, r = − 0 .9570). Vitamin D3 deficiency was linked to higher LVDD grades, independent of glycemic control. Diabetes duration and BMI also correlated with LVDD ( P < 0.001). Conclusion: Vitamin D3 deficiency is significantly associated with LVDD severity in T2DM patients with controlled glycemia, suggesting it as an independent risk factor. Future research should investigate vitamin D3 supplementation for cardiovascular risk management in T2DM.