JMIR Publications

ABSTRACT

Background:

Vitamin D deficiency has been found to be associated with hypertensive disorders in pregnancy. The risk of hypertension was reported to be further augmented among those with vitamin D receptor (VDR) gene polymorphism. The genetic variants in VDR gene were inconsistent in different population.

Objective:

we aim to examine the association of vitamin D status and VDR gene polymorphisms with hypertensive disorders of pregnancy (HDP) among Malaysian pregnant women.

Methods:

This prospective study consists of two phases. The first phase, a cross-sectional study is based on medical records, questionnaire survey and laboratory testing for vitamin D status. The estimated sample size is 414 pregnant women of various ethnicity. Height, weight, body mass index at booking and gestational age at recruitment will be obtained from medical records. Questionnaire will be utilised to assess the risk factors for vitamin D deficiency. Status of vitamin D will be obtained from the measurement of the vitamin D 25(OH)D3 level in the blood. The second phase is a case-control study involving Malay ethnicity group with vitamin D deficiency. Participants will be divided into 2 groups with 101 subjects in each group; Group 1 (with HDP) and Group 2 (without HDP). Blood will be withdrawn for genetic analysis to determine the frequency and mutations of BsmI, ApaI, TaqI and FokI VDR genotypes. The association of these with development of HDP will be analysed.

Results:

As of October 2023, we have enrolled 150 women for Phase one and 5 women for Phase two in each arm.

Conclusions:

Our findings can be used to develop a policy on routine use of Vitamin D among pregnant women to reduce the risk of hypertensive disease in pregnancy Clinical Trial: This study was approved by the ethics and research committee involving human subjects of the Universiti Putra Malaysia (JKEUPM-2021-915). The registration for ClinicalTrials.gov identifier is NCT05659173.