All-Cause and Cause-Specific Mortality After Hypertensive Disease of Pregnancy

Abstract

Objective: To assess whether women with a history of hypertensive disease of pregnancy have increased risk for early adult mortality.

Methods: In this retrospective cohort study, women with one or more singleton pregnancies (1939-2012) with birth certificate information in the Utah Population Database were included. Diagnoses were categorized into gestational hypertension; preeclampsia; hemolysis, elevated liver enzymes, and low platelet count syndrome; and eclampsia. Women with more than one pregnancy with hypertensive disease (exposed) were included only once, assigned to the most severe category. Exposed women were matched one to two to unexposed women by age, year of childbirth, and parity at the time of the index pregnancy. The causes of death were ascertained using Utah death certificates and the fact of death was supplemented with the Social Security Death Index. Hazard ratios for cause-specific mortality among exposed women compared with unexposed women were estimated using Cox regressions adjusting for neonatal sex, parental education, preterm delivery, race-ethnicity, and maternal marital status.

Results: A total of 60,580 exposed women were matched to 123,140 unexposed women; 4,520 (7.46%) exposed and 6,776 (5.50%) unexposed women had died by 2012. All-cause mortality was significantly higher among women with hypertensive disease of pregnancy (adjusted hazard ratio [HR] 1.65, 95% confidence interval [CI] 1.57-1.73). Exposed women's greatest excess mortality risks were from Alzheimer disease (adjusted HR 3.44, 95% CI 1.00-11.82), diabetes (adjusted HR 2.80, 95% CI 2.20-3.55), ischemic heart disease (adjusted HR 2.23, 95% CI 1.90-2.63), and stroke (adjusted HR 1.88, 95% CI 1.53-2.32).

Conclusion: Women with hypertensive disease of pregnancy have increased mortality risk, particularly for Alzheimer disease, diabetes, ischemic heart disease, and stroke.

Figure 1

Forest plot illustrating risks of general causes of mortality for women with each category of hypertensive disease of pregnancy compared to matched women without hypertensive disease of pregnancy. Created by Jennifer West.

Figure 2

Forest plot illustrating risks of specific causes of mortality for women with each category of hypertensive disease of pregnancy compared to matched women without hypertensive disease of pregnancy. Created by Jennifer West.

Figure 3

Survival curves for survival probability by years since index pregnancy for each category of hypertensive disease of pregnancy compared to women without hypertensive disease of pregnancy. The survival curves for each category of exposed women were significantly different from that for unexposed women and from each other (P value for all <.01). Created by Jennifer West.