Kidney Function After a Hypertensive Disorder of Pregnancy: A Longitudinal Study

Abstract

Background: Registry-based studies report an increased risk for end-stage kidney disease after hypertensive disorders of pregnancy (HDPs). It is unclear whether HDPs lead to an increased incidence of chronic kidney disease (CKD) and/or progression of kidney function decline.

Study design: Subanalysis of the Prevention of Renal and Vascular Endstage Disease (PREVEND) Study, a Dutch population-based cohort with follow-up of 5 visits approximately 3 years apart.

Setting & participants: Women without and with patient-reported HDPs (non-HDP, n=1,805; HDP, n=977) were identified. Mean age was 50 years at baseline and median follow-up was 11 years.

Factor: An HDP.

Outcomes: (1) The incidence of CKD using Cox regression and (2) the course of kidney function (estimated glomerular filtration rate [eGFR] and 24-hour albuminuria) over 5 visits using generalized estimating equation analysis adjusted for age, mean arterial pressure, and renin-angiotensin system (RAS) blockade. CKD was defined as eGFR<60mL/min/1.73m² and/or 24-hour albuminuria with albumin excretion > 30mg, and end-stage kidney disease was defined as receiving dialysis or kidney transplantation.

Results: During follow-up, none of the women developed end-stage renal disease and the incidence of CKD during follow-up was similar across HDP groups (HR, 1.04; 95% CI, 0.79-1.37; P=0.8). Use of RAS blockade was higher after HDP at all visits. During a median of 11 years, we observed a decrease in eGFR in both groups, with a slightly steeper decline in the HDP group (98±15 to 88±16 vs 99±17 to 91±15mL/min/1.73m²; P_group<0.01, P_group*visit<0.05). The group effect remained significant after adjusting for mean arterial pressure, but disappeared after adjusting for RAS blockade. The 24-hour albuminuria did not differ between groups.

Limitations: No obstetric records available. HDPs defined by patient report rather than health records.

Conclusions: HDPs did not detectably increase the incidence of CKD. During follow-up, we observed no differences in albuminuria, but observed a marginally lower eGFR after HDP that was no longer statistically significant after adjusting for the use of RAS blockers. In this population, we were unable to identify a significant risk for kidney function decline after patient-reported HDP.

Keywords: Albuminuria; blood pressure; chronic kidney disease (CKD); end-stage kidney disease (ESKD); gestational hypertension; hypertension; hypertensive disorders of pregnancy; kidney function; preeclampsia; proteinuria.