Background: Hypertensive disorders of pregnancy (HDP) are associated with a significant increase in the lifetime risk of cardiovascular and chronic kidney disease. Albuminuria is an early biomarker of this risk, but longitudinal postpartum data are sparse. We quantified albuminuria prevalence and persistence up to 18 months postpartum following HDP.
Materials and Methods: This retrospective cohort study (2018–2026) evaluated women with high-risk pregnancies at 6 and 18 months postpartum. The primary outcome was the incidence of an elevated urinary albumin-to-creatinine ratio (uACR). Mixed-effects regression and generalized estimating equations were utilised to adjust for confounders.
Results: In 694 women (mean age 32.1 years), those with HDP(n=317) had higher mean uACR (1.63mg/mmol [95% CI 1.37–1.89] vs. 1.08 mg/mmol [95% CI 0.91–1.24]) at 6 months postpartum and a more than twofold increase in the odds of albuminuria 3mg/mmol (Odds ratio 2.12, 95% CI: 1.21 to 3.72, p = 0.009) compared to the non-HDP group (n=377). Risk of albuminuria was highest in women with concomitant HDP and diabetes (adjusted ln coefficient 1.14, p = 0.017). By the 18-month follow-up (n=340), geometric mean UACR in the HDP cohort declined to 1.07 mg/mmol (95% CI: 0.86 to 1.29)(similar to those without HDP), but 11% of the HDP cohort still had clinically significant albuminuria (3mg/mmol).
Conclusion: HDP is associated with adverse renal effects lasting 6–18 months postpartum. While albuminuria improves for most, a high-risk subgroup, particularly those with concomitant diabetes, exhibits persistent proteinuria. Structured surveillance and intervention are necessary to mitigate long-term cardiorenal morbidity.