In the JournalsPerspective

Even small BP elevation during pregnancy may predict future hypertension

Elevated blood pressure that still falls below the diagnostic criteria for hypertensive disorders of pregnancy is associated with the development of hypertension 5 years later, according to findings published in Clinical Endocrinology.

Michelle B. Brady

“Those with slight elevations in blood pressure in pregnancy could be flagged for follow-up postpartum for annual blood pressure checks to manage their future hypertension risk,” Michelle B. Brady, BSc, MSc, RD, a registered dietitian with the Perinatal Research Centre at University College Dublin School of Medicine, Ireland, told Endocrine Today. “Further observational studies are needed to confirm the above findings, and clinical trials to determine nonpharmacological interventions, such as changes to dietary pattern, could provide insight into how to manage or reduce future hypertension risk in this female cohort.”

In a prospective, observational study, Brady and colleagues analyzed data from 329 white women who participated in the ROLO study conducted at National Maternity Hospital in Dublin between 2007 and 2011. Researchers assessed maternal BP measurements taken at 13, 28 and 34 weeks’ gestation, 1 day postpartum and again at the 5-year follow-up visit. At each visit, systolic BP and diastolic BP were defined as normal (systolic BP < 120 mm Hg; diastolic BP < 80 mm Hg), elevated (systolic BP between 120-129 mm Hg; diastolic BP < 80 mm Hg), stage 1 hypertension (systolic BP between 130-139 mm Hg; diastolic BP between 80-89 mm Hg) or stage 2 hypertension (systolic BP 140 mm Hg; diastolic BP 90 mm Hg). Primary outcome was maternal BP at 5 years.

At the 5-year follow-up visit, 58.7% had normal BP, 14.6% of women had elevated BP, 18.2% had stage 1 hypertension and 8.5% had stage 2 hypertension.

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Elevated blood pressure that still falls below the diagnostic criteria for hypertensive disorders of pregnancy is associated with the development of hypertension 5 years later.

Researchers found that women with elevated BP at 28 weeks’ gestation were 2.68 times more likely to have stage 1 hypertension at 5 years when compared with women who had normal BP during pregnancy (95% CI, 1.36-5.26). Similarly, elevated BP at 34 weeks’ gestation was associated with a 2.45-fold increase in risk for stage 1 hypertension at 5 years vs. women with normal BP during pregnancy (95% CI, 1.22-4.95). Each 1 mm Hg increase in systolic BP and diastolic BP at 34 weeks’ gestation was associated with 1.04 and 1.05 increased odds, respectively, for the development of stage 1 and stage 2 hypertension at 5-year follow-up. Additionally, each 1 mm Hg increase in mean arterial pressure at 34 weeks’ gestation was associated with 1.05-fold and 1.08-fold increased risk for stage 1 and stage 2 hypertension at 5 years, respectively.

“This research suggests the application of BP thresholds used in nonpregnant populations to pregnant populations to identify those at risk of future hypertension,” the researchers wrote. “Annual BP checks within primary care, following elevated BP at 28 and 34 weeks’ gestation, may help manage such risk. The evidence presented also suggests that mean arterial pressure should routinely be used to evaluate BP in pregnancy.” – by Regina Schaffer

For more information:

Michelle B. Brady, BSc, MSc, RD, can be reached at the Perinatal Research Centre, School of Medicine, University College Dublin, Health Science Center, Roebuck, Ireland; email: michelle.brady.2011@gmail.com.

Disclosures: The authors report no relevant financial disclosures.

Elevated blood pressure that still falls below the diagnostic criteria for hypertensive disorders of pregnancy is associated with the development of hypertension 5 years later, according to findings published in Clinical Endocrinology.

Michelle B. Brady

“Those with slight elevations in blood pressure in pregnancy could be flagged for follow-up postpartum for annual blood pressure checks to manage their future hypertension risk,” Michelle B. Brady, BSc, MSc, RD, a registered dietitian with the Perinatal Research Centre at University College Dublin School of Medicine, Ireland, told Endocrine Today. “Further observational studies are needed to confirm the above findings, and clinical trials to determine nonpharmacological interventions, such as changes to dietary pattern, could provide insight into how to manage or reduce future hypertension risk in this female cohort.”

In a prospective, observational study, Brady and colleagues analyzed data from 329 white women who participated in the ROLO study conducted at National Maternity Hospital in Dublin between 2007 and 2011. Researchers assessed maternal BP measurements taken at 13, 28 and 34 weeks’ gestation, 1 day postpartum and again at the 5-year follow-up visit. At each visit, systolic BP and diastolic BP were defined as normal (systolic BP < 120 mm Hg; diastolic BP < 80 mm Hg), elevated (systolic BP between 120-129 mm Hg; diastolic BP < 80 mm Hg), stage 1 hypertension (systolic BP between 130-139 mm Hg; diastolic BP between 80-89 mm Hg) or stage 2 hypertension (systolic BP 140 mm Hg; diastolic BP 90 mm Hg). Primary outcome was maternal BP at 5 years.

At the 5-year follow-up visit, 58.7% had normal BP, 14.6% of women had elevated BP, 18.2% had stage 1 hypertension and 8.5% had stage 2 hypertension.

#
Elevated blood pressure that still falls below the diagnostic criteria for hypertensive disorders of pregnancy is associated with the development of hypertension 5 years later.

Researchers found that women with elevated BP at 28 weeks’ gestation were 2.68 times more likely to have stage 1 hypertension at 5 years when compared with women who had normal BP during pregnancy (95% CI, 1.36-5.26). Similarly, elevated BP at 34 weeks’ gestation was associated with a 2.45-fold increase in risk for stage 1 hypertension at 5 years vs. women with normal BP during pregnancy (95% CI, 1.22-4.95). Each 1 mm Hg increase in systolic BP and diastolic BP at 34 weeks’ gestation was associated with 1.04 and 1.05 increased odds, respectively, for the development of stage 1 and stage 2 hypertension at 5-year follow-up. Additionally, each 1 mm Hg increase in mean arterial pressure at 34 weeks’ gestation was associated with 1.05-fold and 1.08-fold increased risk for stage 1 and stage 2 hypertension at 5 years, respectively.

“This research suggests the application of BP thresholds used in nonpregnant populations to pregnant populations to identify those at risk of future hypertension,” the researchers wrote. “Annual BP checks within primary care, following elevated BP at 28 and 34 weeks’ gestation, may help manage such risk. The evidence presented also suggests that mean arterial pressure should routinely be used to evaluate BP in pregnancy.” – by Regina Schaffer

For more information:

Michelle B. Brady, BSc, MSc, RD, can be reached at the Perinatal Research Centre, School of Medicine, University College Dublin, Health Science Center, Roebuck, Ireland; email: michelle.brady.2011@gmail.com.

Disclosures: The authors report no relevant financial disclosures.

    Perspective
    Margo B. Minissian

    Margo B. Minissian

    Hypertension in pregnancy has long been defined as a systolic blood pressure of at least 140 mm Hg or a diastolic BP of at least 90.1 mm Hg. Further, it is well accepted that women who develop hypertension in pregnancy — whether gestational hypertension or preeclampsia — have a significant risk for developing CVD, including hypertension, in the years after pregnancy. Therefore, if maternal BP never reaches a level defined as gestational hypertension, women are not routinely followed for later development of hypertension or CVD. Recently, new cardiac guidelines have delineated new definitions of concerning BP thresholds for nonpregnant women. Thus, the study authored by Brady and colleagues asked an important question: Is maternal BP less than 140/90 mm Hg associated with maternal BP 5 years after the index pregnancy? More specifically, the authors were interested in whether applying the new definitions of nonpregnant, elevated BP to pregnant women would predict which women may develop hypertension within 5 years after their pregnancy.

    Those women who had elevated blood pressure demonstrated a significant 2.4-2.7-fold increased risk for stage 1 hypertension, but not stage 2 hypertension at 5 years postpartum compared with women who did not experience elevations in BP during pregnancy. Interestingly, however, there were no significant increased odds for stage 1 or 2 hypertension among pregnant women who had stage 1 or 2 hypertension during pregnancy.

    Their findings are provocative, and warrant thought by the obstetric community and suggest that a BP in the elevated range should be noted. However, the finding that stage 1 and stage 2 hypertensive levels in pregnancy were not associated with later hypertension, which as they note could be due to small sample size, is troublesome in its inconsistency and warrants additional studies. Finally, one cannot forget that all of these women had a prior macrosomic baby and essentially all were white, so the generalizability of the findings is limited. However, these are additional data that BP elevation in pregnancy may help predict who will be at increased future risk for hypertension.

    • Margo B. Minissian, PhD, ACNP, FNLA, FAHA
    • Research Scientist, Clinical Lipid Specialist and Cardiology Nurse Practitioner
      Barbra Streisand Women’s Heart Center
      Smidt Heart Institute at Cedars-Sinai

    Disclosures: Minissian reports no relevant financial disclosures.