Prehypertension During Normotensive Pregnancy and Postpartum Clustering of Cardiometabolic Risk Factors

As a result of biphasic changes in peripheral arterial resistance during pregnancy, the blood pressure (BP) level undergoes a gradual decrease to the nadir at midpregnancy and returns to a prepregnant level through term. Consequently, this physiological alteration leads to the question of whether the criteria for the diagnosis of gestational hypertension are suitable because the current criteria (systolic BP [SBP] ≥140 mm Hg and diastolic BP [DBP] ≥90 mm Hg) are derived from the nonpregnant population. The optimal BP levels in pregnant women remain an open question. Emerging evidence shows that prehypertension (120– 139/80–89 mm Hg), defined by the seventh report of the Joint National Committee on Prevention, not only increases the risk of incident hypertension but also is associated with an increased risk of cardiovascular disease (CVD). Although prehypertension is not addressed by the eighth Joint National Committee on Prevention, the diagnosis of prehypertension provides a unique understanding of when future CVD trajectories could be changed by lifestyle modifications. Recent studies have demonstrated associations between prehypertension before pregnancy and hypertensive disorders during pregnancy and gestational diabetes mellitus. To our knowledge, the association between prehypertension during pregnancy and postpartum cardiovascular risk has not been addressed. Pregnancy is a known, long-term cardiovascular stress test for women. The presence of hypertensive disorders in pregnancy (HDP) is generally recognized as a maladaptation to pregnancyinduced hemodynamic and metabolic alterations. In addition, Abstract—The nonstratification of blood pressure (BP) levels may underestimate future cardiovascular risk in pregnant women who present with BP levels in the range of prehypertension (120–139/80–89 mm Hg). We prospectively evaluated the relationship between multiple antepartum BP measurements (from 11 to 13 weeks’ gestation to term) and the occurrence of postpartum metabolic syndrome in 507 normotensive pregnant women after a live birth. By using latent class growth modeling, we identified the following 3 distinctive diastolic BP (DBP) trajectory groups: the low-J-shaped group (34.2%; DBP from 62.5±5.8 to 65.0±6.8 mm Hg), the moderate-U-shaped group (52.6%; DBP from 71.0±5.9 to 69.8±6.2 mm Hg), and the elevated-J-shaped group (13.2%; DBP from 76.2±6.7 to 81.8±4.8 mm Hg). Notably, the elevated-J-shaped trajectory group had mean DBP and systolic BP levels within the range of prehypertension from 37 and 26 weeks of pregnancy, respectively. Among the 309 women who completed the ≈1.6 years of postpartum follow-up, the women in the elevated-Jshaped group had greater odds of developing postpartum metabolic syndrome (adjusted odds ratio, 6.55; 95% confidence interval, 1.79–23.92; P=0.004) than the low-J-shaped group. Moreover, a parsimonious model incorporating DBP (membership in the elevated-J-shaped group but not in the DBP prehypertension group as identified by a single measurement) and elevated levels of fasting glucose (>4.99 mmol/L) and triglycerides (>3.14 mmol/L) at term was developed, with good discrimination and calibration for postpartum metabolic syndrome (c-statistic, 0.764; 95% confidence interval, 0.674– 0.855; P<0.001). Therefore, prehypertension identified by DBP trajectories throughout pregnancy is an independent risk factor for predicting postpartum metabolic syndrome in normotensive pregnant women. (Hypertension. 2016;68:00-00. DOI: 10.1161/HYPERTENSIONAHA.116.07261.) • Online Data Supplement