Blood pressure control, hypertension phenotypes, and albuminuria: outcomes of the comprehensive Basel Postpartum Hypertension Registry

Abstract

Postpartum hypertension (PPHT) affects 20% of pregnancies and is strongly correlated to cardiovascular and kidney disease. Most outcome data stems from preeclampsia (PE) neglecting other hypertensive disorders of pregnancy (HDP). This analysis aimed to investigate blood pressure (BP) control, BP phenotypes, therapeutic intensity scores (TIS), and albuminuria across the spectrum of PPHT in the short-medium term.This analysis prospectively followed 370 cases of PPHT. Automated office BP measurements (AOBPM), 24-hour ambulatory BP measurements (24ABPM), TIS and Kidney Disease Improving Global Outcomes (KDIGO) > A2 levels of albumin to creatinine ratio (ACR) were measured at 3 (V3) and 12 (V12) months postpartum. Outcomes were percentage of participants with non-hypertensive AOBPM and awake 24ABPM, whitecoat, and masked hypertension, and an A2 ACR at V3 and V12. The Basel-PPHT cohort consisted of 11.9% (n = 44) chronic hypertension, 31.9% (n = 118) gestational hypertension, 55.4% (n = 205) PE, eclampsia or HELLP, and 18.4% (n = 68) de novo PPHT. Antihypertensive medication was prescribed at baseline, V3 and V12 in 85.4% (n = 316), 19.2% (n = 46), and 20% (n = 21). At V12, 9.3% (n = 5) with PE, eclampsia, and HELLP vs 31.4% (n = 16) of the remaining cohort required antihypertensive medication, p = 0.005. Non-hypertensive BP without medication was seen at V3 and V12 in 47.9% (n = 103) and 62.4% (n = 63), respectively. Albuminuria at baseline, V3 and V12 was 84.9% (n = 124), 29.9% (n = 63), and 16.9% (n = 14) respectively. The Basel-PPHT registry identified undertreatment and persistent albuminuria, despite structured management. Importantly, those without preeclampsia also required stricter controls. Therefore, rigorous follow-ups are crucial for enhancing cardiovascular and renal outcomes in this population.

Keywords: Blood pressure phenotypes; Cardiovascular risk; Hypertensive disorders in pregnancy; Postpartum hypertension.

Fig. 1

Flow Chart of all Participants included in the Basel-PPHT Registry. CBP clinic blood pressure, 24hABPM 24-hour ambulatory blood pressure measurement, AOBPM automated office blood pressure measurement. *lost to follow up through to canceled appointment, non-appearance, or further care provided by the family doctor

Fig. 2

Blood pressure outcomes at 3 and 12 months for the full cohort and the subgroups of patients with and without preeclampsia. hypertensive with medication hypertensive without medication non-hypertensive with medication non-hypertensive without medication. Stacked column chart comparing the different blood pressure measurement types (24hABP mean, awake, asleep and AOBPM) at V3 and V12 for the full cohort and the subgroups of patients with and without preeclampsia. Only participants, who had all four different BPM were included in the figure. Columns show the different BP control: hypertensive with medication, hypertensive without medication, non-hypertensive without medication and non-hypertensive with medication

Fig. 3

Blood Pressure Phenotypes: True Non-hypertensive, Sustained Hypertension, White-Coat Hypertension, Masked Hypertension. Comparison of AOBPM and 24ABPM at 3 and 12 months postpartum to identify blood pressure phenotypes (true non-hypertensive, masked hypertension, white-coat hypertension and sustained Hypertension). Data is presented as n (%)

Fig. 4

Prevalence of albuminuria at V3 and V12, 3 and 12 months respectively. ACR < KDIGO A2 ACR ≥ KDIGO A2. Stacked column chart comparing the prevalence of albuminuria in participants with normotensive blood pressure with and without medication and those with hypertensive awake 24ABP blood pressure with and without medication at V3 and V12. Relevant levels of albumin to creatinine ratio (ACR) albuminuria was based on the classification: Kidney Disease Improving Global Outcomes (KDIGO) ≥ A2