The effect of preeclampsia on long-term kidney function among pregnant women with chronic kidney disease

ABSTRACT Background The association between superimposed preeclampsia and an elevated risk of long-term kidney function decline or end-stage kidney disease (ESKD) in patients with chronic kidney disease (CKD) has not been determined. This study aimed to analyze the association between preeclampsia and kidney function deterioration in CKD patients. Methods This was a retrospective cohort study that included the clinical information of 103 pregnant CKD patients with preeclampsia and 103 matched CKD patients without preeclampsia who were followed-up for a minimum of 1 year after their first pregnancy from 1 January 2009 to 31 May 2022. Robust Cox regression analysis was also conducted to evaluate the effects of preeclampsia on long-term kidney function decline or ESKD in CKD patients. Kaplan–Meier curves were used to compare renal survival within different subgroups via the log-rank test. Results During the follow-up period, 44 (42.72%) CKD patients with preeclampsia and 20 (19.42%) without preeclampsia had an estimated glomerular filtration rate (eGFR) decrease >30% or developed ESKD. Compared with CKD patients without preeclampsia, the eGFR decreased more significantly in patients with preeclampsia [98.43 (79.48, 116.47) to 81.32 (41.20, 102.97) mL/min/1.73 m2 vs 99.43 (79.00, 118.50) to 89.44 (63.69, 105.30) mL/min/1.73 m2; P = .034]. The rate of eGFR decrease was more pronounced in patients with preeclampsia (17.38% vs 10.05%, P < .05). Multivariate analysis revealed that early-onset preeclampsia (preeclampsia that developed before 34 weeks of gestation) [hazard ratio (HR) = 2.61, 95% confidence interval (CI) 1.32–5.16, P = 0.006] and late-onset preeclampsia (HR = 2.54, 95% CI 1.34–4.83, P = .004) were both risk factors for an eGFR decrease >30% or ESKD. Conclusion Preeclampsia was associated with a greater risk of long-term kidney function decline or ESKD among CKD patients, especially in patients with early-onset preeclampsia.