Serum vitamin D in hypertensive patients versus healthy controls is there an association?

Background: Both vitamin D deficiency and hypertension are prevalent in the general population. Several observations indicate an association between vitamin D deficiency and high blood pressure. The present case-control study aimed to compare serum 25-hydroxyvitamin D (25-OHD) in hypertensive patients versus healthy controls.

Methods: One hundred patients aged 30-60 years with hypertension (HTN) and 100 healthy controls without history of hypertention were compared regarding serum 25-OHD. Blood pressure was measured using standard method and the systolic and diastolic blood pressure more than140 mmHg and 90 mmHg respectively were considered as HTN. Patients and controls with coexistent morbidities, vitamin D supplementation were excluded. The serum levels of 25-OHD, PTH and calcium were measured after obtaining a written informed consent from the patients and taking their blood pressure under standard conditions. In statistical analysis, the two groups were compared using independent t test and chi-square test using SPSS Version 18.

Results: The mean age of patients and controls was comparable (53.7±6.4 vs 52.3±7.54 years, P=0.17). Serum 25-OHD in HTN was significantly higher than controls (P=0.001).

Conclusion: In the present study, serum 25-OHD level in hypertension was higher than controls. The results contradict with earlier studies indicating an association of HTN with vitamin D deficiency. This issue warrants further investigations in particular the follow-up of serum 25-OHD deficient and sufficient subjects with regard to the development of HTN.