Detection of hypertension and blood pressure phenotypes using ambulatory blood pressure monitoring in women with past hypertensive disorders of pregnancies.

OBJECTIVE

To evaluate the incidence of hypertension and blood pressure (BP) phenotypes using 24-hour ambulatory BP (24hr-ABP) in women with past pregnancy complications who were recruited into a Women's Heart Clinic (WHC).

STUDY DESIGN

We recruited 156 women aged 30-55 years with past hypertensive disorders of pregnancy (HDP) and/or gestational diabetes (GDM) to a multidisciplinary six-month WHC that provided cardiovascular risk management in Melbourne, Australia. Women were referred for 24 hr-ABP monitoring if clinic BP was ≥130/80 mmHg.

MAIN OUTCOME MEASURES

Primary outcome was incident hypertension, defined by 24 hr-ABP monitoring as daytime hypertension ≥135/85 mmHg, nocturnal hypertension ≥120/70 mmHg, and/or 24hr-average hypertension ≥130/80 mmHg.

RESULTS

From 156 women, 54 women underwent 24hr-ABP monitoring (mean age 41.3 ± 4.5 years; 3.9 ± 2.6 years post-partum), with 64.8 % HDP and 45.2 % GDM. Incidence of hypertension was 61.1 % [95 % CI 48.2 %-74.0 %]. Higher proportion of women with past HDP had daytime hypertension compared to those with GDM only (57.1 % vs. 26.3 %; p = 0.05) and higher nocturnal mean systolic-BP [116.0 ± 11.2 mmHg vs. 109.6 ± 8.7 mmHg; p = 0.04]. Women with HDP had increased odds of hypertension [adjusted-OR 5.26 95 % CI (1.07-32.76); p = 0.05]. Following management at the WHC, women diagnosed with hypertension had significantly improved BP control (6.1 % at baseline vs. 75.8 % at six-month follow-up; p < 0.001).

CONCLUSION

Women with past HDP had five-fold increased incidence of hypertension, with higher daytime hypertension and nocturnal systolic-BP, compared to women with GDM. After attending WHC, BP control significantly improved. Our findings suggest routine postpartum follow-up with 24hr-ABP monitoring, through a WHC, may be useful in early detection and management of hypertension in these women.