HealthDay News — Overall, 0.63 percent of women experience chronic hypertension during pregnancy, with the rate increasing with maternal age and year of delivery, according to a study published online Sept. 9 in Hypertension.
Cande V. Ananth, Ph.D., M.P.H., from the Rutgers Robert Wood Johnson Medical School in New Brunswick, New Jersey, and colleagues conducted a cross-sectional analysis of more than 151 million women with delivery-related hospitalizations in the United States from 1970 to 2010. The prevalence rates and rate ratios (RRs) of chronic hypertension were derived in relation to age, period, and birth cohort through age-period-cohort (APC) models.
The researchers found that the overall prevalence of chronic hypertension was 0.63 percent, with the rate more than twofold higher for black versus white women (1.24 versus 0.53 percent; RR, 2.31). The rate of chronic hypertension increased sharply with advancing age and period in the APC analysis, from 0.11 to 1.52 percent from 1970 to 2010 (RR, 13.41). On average, the rate of hypertension increased by 6 percent per year, with a slightly higher increase among white compared with black women (7 versus 4 percent). There was no correlation for adjustments in the rates of obesity and smoking with age and period effects.
“We were very surprised that the increasing prevalence of obesity and the declining prevalence of smoking rates had virtually no impact on trends in chronic hypertension during pregnancy,” Ananth said in a statement.