A study presented at the ESH Congress 2026 evaluated the effects of cholecalciferol supplementation on endothelial function in 102 women with stage II arterial hypertension and high cardiovascular risk. Participants were categorized as either premenopausal or early postmenopausal and underwent assessment of serum 25-hydroxyvitamin D [25(OH)D] levels and endothelial function using endothelium-dependent vasodilation (EDV).

Women with vitamin D levels below 30 ng/mL received cholecalciferol 2,000 IU daily for three months in addition to antihypertensive therapy, while comparison groups continued antihypertensive treatment without vitamin D supplementation.

Findings

• Baseline 25(OH)D levels were significantly lower among women selected for supplementation, averaging 19.3 ± 8.5 ng/mL in premenopausal women and 18.2 ± 9.5 ng/mL in postmenopausal women (P<0.05 versus comparison groups).
• After three months of supplementation, mean 25(OH)D levels increased to 37.3 ± 12.0 ng/mL in premenopausal women and 36.4 ± 10.0 ng/mL in postmenopausal women (P<0.001 for both).
• Endothelium-dependent vasodilation improved significantly following therapy in all study groups (P<0.01).
• Early postmenopausal women receiving cholecalciferol showed greater improvement in endothelium-dependent vasodilation than those who did not receive supplementation (P=0.04).
• The prevalence of endothelial dysfunction was lower among supplemented postmenopausal women compared with those not receiving cholecalciferol (14.3% vs 35.5%; P=0.05).

The findings suggest that correction of vitamin D deficiency with cholecalciferol may improve endothelial function in women with arterial hypertension, with particularly favorable effects observed in the early postmenopausal period.