Maternal vitamin D status and the risk of mild and severe preeclampsia.

Abstract

BACKGROUND:

We sought to determine the association between maternal vitamin D status at ≤26 weeks' gestation and the risk of preeclampsia by clinical subtype.

METHODS:

We conducted a case-cohort study among women enrolled at 12 US sites from 1959 to 1966 in the Collaborative Perinatal Project. In serum collected at ≤26 weeks' gestation (median 20.9 weeks) from 717 women who later developed preeclampsia (560 mild and 157 severe cases) and from 2986 mothers without preeclampsia, we measured serum 25-hydroxyvitamin D, over 40 years later, using liquid chromatography-tandem mass spectrometry.

RESULTS:

Half of women in the subcohort had 25-hydroxyvitamin D (25(OH)D) >50 nmol/L. Maternal 25(OH)D 50 to 74.9 nmol/L was associated with a reduction in the absolute and relative risk of preeclampsia and mild preeclampsia compared with 25(OH)D <30 nmol/L in the crude analysis but not after adjustment for confounders, including race, prepregnancy body mass index, and parity. For severe preeclampsia, 25(OH)D ≥50 nmol/L was associated with a reduction in three cases per 1000 pregnancies (adjusted risk difference = -0.003 [95% confidence interval = -0.005 to 0.0002]) and a 40% reduction in risk (0.65 [0.43 to 0.98]) compared with 25(OH)D <50 nmol/L. Conclusions were unchanged (1) after restricting to women with 25(OH)D measured before 22 weeks' gestation or (2) with formal sensitivity analyses for unmeasured confounding.

CONCLUSIONS:

Maternal vitamin D deficiency may be a risk factor for severe preeclampsia but not for its mild subtypes. Contemporary cohorts with large numbers of severe preeclampsia cases would be needed to confirm or refute these findings.

• Authors: Lisa M Bodnar, Hyagriv N Simhan, Janet M Catov, James M Roberts, Robert W Platt, Jill C Diesel, Mark A Klebanoff
• Journal: Epidemiology (Cambridge, Mass.) (Epidemiology) Vol. 25 Issue 2 Pg. 207-14 (Mar 2014) ISSN: 1531-5487 [Electronic] United States
• PMID: 24457526 (Publication Type: Journal Article, Multicenter Study, Research Support, N.I.H., Extramural)

Chemical References

• Biomarkers
• Vitamin D
• 25-hydroxyvitamin D

Topics

• Adult
• Biomarkers (blood)
• Case-Control Studies
• Chromatography, Liquid
• Female
• Humans
• Logistic Models
• Markov Chains
• Monte Carlo Method
• Odds Ratio
• Pre-Eclampsia (etiology)
• Pregnancy
• Pregnancy Trimester, First (blood)
• Pregnancy Trimester, Second (blood)
• Risk Factors
• Severity of Illness Index
• Tandem Mass Spectrometry
• Vitamin D (analogs & derivatives, blood)
• Vitamin D Deficiency (blood, complications, diagnosis)