Background:
Gestational hypertension (GHTN) remains a compelling clinical and public health problem. It can increase risks of intrauterine growth restriction, low-birth weight, and stillbirth. Little is known about whether racial and ethnic minorities and lower socio-economic status (SES) population groups are more vulnerable to GHTN.
Hypothesis:
We hypothesized that racial and ethnic disparities in GHTN exist beyond the scope of SES-related health disparities.
Methods:
A case-control study of GHTN was conducted using the data of 114,298 births in the year 2010 in Ohio. The comprehensive births data were obtained from Ohio Department of Health. Cases were identified as those with GHTN. Controls were identified as those without GHTN. Mothers utilizing Medicaid or the Federal Special Supplemental Nutrition Program for Women, Infants and Children were considered of low SES. Odds ratios of GHTN in relation to mother’s race, ethnicity, and SES were obtained using multivariable logistic regression (SAS software), adjusting for known confounders - gestational age, mother’s age, pre-pregnancy and pregnancy smoking status, pre-pregnancy or gestational diabetes, and plurality.
Results:
GHTN was statistically significantly associated with maternal race and ethnicity, even after adjustment for SES. Compared to non-Hispanic whites, non-Hispanic blacks were more likely to develop GHTN (adjusted OR = 1.867, 95% CI 1.663–2.096, p<0.001), while Asian women were less likely to develop GHTN (adjusted OR = 0.538, 95% CI 0.426–0.679, p<0.001). Hispanic white women were less likely to develop GHTN than non-Hispanic white women, although the difference between them did not reach a conventional p<0.05 level of statistical significance (adjusted OR = 0.651, 95% CI 0.395–1.076, p=0.09). Adjusted for maternal race, ethnicity, age, and known clinical confounders, women of lower SES were more likely to develop GHTN (adjusted OR = 1.475, 95% CI 1.32–1.647, p<0.001).
Conclusions:
Non-Hispanic black women are at the highest risk of developing GHTN, while Asian women are at the lowest. The Hispanic paradox phenomenon extends to the issue of GHTN. Racial and ethnic disparities cannot be attributed to low SES only; other mechanisms need to be investigated further.