Impact of the Glycemic Control and Duration of Type 2 Diabetes on Vitamin D Level and Cardiovascular Disease Risk

Abstract EN

Background and Aims.

To investigate the impact of glycemic control and T2D duration on vitamin D status and cardiovascular disease (CVD) risk among Saudi patients.

Methods.

This case-control study was conducted in King Faisal Specialist Hospital, Saudi Arabia.

A total of 25 nondiabetic controls and 92 patients with confirmed T2D, aged 20–60 years, were included.

Patients with T2D were divided into the following groups based on disease duration (newly diagnosed: ≈6 months and long duration: ≥5 years) and glycemic control based on their glycated hemoglobin (HbA1C) level with a threshold of ≤0.053 mol/mol: newly diagnosed controlled (NC, n=25), newly diagnosed uncontrolled (NU, n=17), long duration controlled (LC, n=25), and long duration uncontrolled (LU, n=25).

Blood levels of fasting blood glucose, HbA1C, lipid profile, and serum 25-hydroxyvitamin D (25(OH)D) were assessed and used to define the CVD risk score.

Results.

Our study showed that T2D duration was an independent predictor of vitamin D deficiency.

The longer disease duration, the lower odds of being vitamin D deficient (odds ratio (OR) = 0.05, 95% CI: 0.01–0.29, p<0.05).

No significant association was observed between vitamin D and HbA1C levels.

In the NU group, CVD risk scores were directly correlated with serum 25(OH)D (r=0.53, p<0.05).

On the contrary, 25(OH)D was moderately inversely correlated with CVD risk score in the LU group (r=−0.45, p<0.05).

Conclusion.

Duration of diabetes rather than glycemic control is associated with vitamin D deficiency.

Glycemic uncontrol may augment vitamin D deficiency-associated CVD risk in both newly diagnosed and old patients with type 2 diabetes.