Drop in Vitamin D Implies Increased Cardiovascular Risk in T2D, According to New Research

A decrease in vitamin D levels is associated with increased cardiovascular risk (CVR) in patients with type 2 diabetes (T2D), according to new research to be presented at the 17th Annual Cardiometabolic Health Congress, held October 19-22, 2022.

“Vitamin D deficiency is common in obese individuals, and that lower circulating concentrations may contribute to increase in metabolic risk,” wrote researchers from Vuk Vrhovac University Clinic for Diabetes, Endocrinology, and Metabolic Diseases, Croatia, in the study abstract.

Absorption of vitamin B12, which is involved in the regulation of homocysteine (HCY) level, decreases with vitamin D deficiency, according to the team. An increase in HCY level may increase CVR, partly because of an impact on apolipoproteins and inflammatory markers. Investigators aimed to determine a possible association between vitamin D and visceral obesity and HCY.

They tested several diabetes-related markers in 613 patients with T2D, including HCY, 25-hydroxyvitamin D, vitamin B12, lipids, and lipid accumulation product (LAP). LAP as an index, combining waist circumference and triglyceride level, is related to risk of metabolic syndrome, diabetes, and CVR, researchers added.

Participants were divided into the following 4 groups according to LAP quartiles:

Groups according to LAP quartiles

1st group

LAP ≤ 28.5

2nd group

28.5 < LAP ≤ 50.59

3rd group

50.59 < LAP ≤ 80.64

4th group

LAP ≥ 80.64

Results showed a significant difference in vitamins D and B12, and high-density lipoprotein (HDL) according to LAP groups. HDL differed significantly between the 1st and the 3rd, and between the 1st and the 4th group, vitamin D between the 1st and the 3rd, and between the 1st and the 4th group, and vitamin B12 differed significantly between the 1st and the 2nd group.

After stepwise regression, the 2 best predictive variables for vitamin D were glomerular filtration rate (GFR) (parR2=0.12) and LAP (parR2=0.07), according to researchers. For vitamin B12, HCY (parR2=0.07) and age (parR2=0.07) were the best predictive variables, and for HCY, it was GFR (parR2=0.23) and vitamin B12 (parR2=0.09).

“Vitamins D and B12 differed according to quartiles of LAP, implying an influence of central obesity on their levels,” concluded authors. They also noted that the relationship between vitamin D, vitamin B12, and HCY implied the involvement of decreased vitamin D in increased CVR.