Effect of race/ethnicity on hypertension risk subsequent to gestational diabetes mellitus.

Gestational diabetes mellitus (GDM) prevalence is greater in racially/ethnically diverse groups compared with non-Hispanic white populations. Although race has been shown to modify other cardiovascular disease risk factors in postpartum women, the role of race/ethnicity on GDM and subsequent hypertension has yet to be examined. The aim of this study was to evaluate the impact of race/ethnicity in relation to GDM and subsequent hypertension in a retrospective analysis of women who delivered at Massachusetts General Hospital from 1998 to 2007. Multivariate analyses were used to determine the associations between GDM and (1) race/ethnicity, (2) hypertension, and (3) the interaction with hypertension and race/ethnicity. Women were monitored for a median of 3.8 years from the date of delivery. In our population of 4,010 women, GDM was more common in nonwhite participants (p<0.0001). GDM was also associated with hypertension subsequent to delivery after adjusting for age, race, parity, first-trimester systolic blood pressure, body mass index, maternal gestational weight gain, and preeclampsia (hazard ratio [HR] 1.75, 95% confidence interval [CI] 1.28 to 2.37, p=0.0004). Moreover, Hispanic (HR 3.25, 95% CI 1.85 to 5.72, p<0.0001) and white (HR 1.68, 95% CI 1.10 to 2.57, p=0.02) women with GDM had greater hypertension risk relative to their race/ethnicity-specific counterparts without GDM in race-stratified multivariable analyses. In conclusion, Hispanic women compared with white women have an increased risk of hypertension. Hispanic and white women with GDM are at a greater risk for hypertension compared with those without GDM. Because the present study may have had limited power to detect effects among black and Asian women with GDM, further research is warranted to elucidate the need for enhanced hypertension risk surveillance in these young women.