Kidney Week

Abstract: SA-PO1088

Renin-Angiotensin System Blockade Does Not Alter Long-Term Kidney Outcomes in Sickle Cell Disease

Session Information

• CKD: Epidemiology, Risk Factors, and Prevention - 3
  October 26, 2024 | Location: Exhibit Hall, Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: CKD (Non-Dialysis)

• 2301 CKD (Non-Dialysis): Epidemiology, Risk Factors, and Prevention

Author

• Olaniran, Kabir O., The University of Texas Southwestern Medical Center Department of Internal Medicine, Dallas, Texas, United States

Kabir O. Olaniran, MD, MPH

Background

Sickle disease (SCD) is associated with faster kidney function decline compared to normal hemoglobin phenotypes. The role of renin angiotensin system inhibitors (RASI) in modifying long-term kidney outcomes in SCD is not well described despite several studies showing antiproteinuric effects of RASI in SCD. This study aimed to describe long-term kidney outcomes in adult SCD patients on RASI.

Methods

A single-center observational study of adult patients with SCD on RASI (exposure) and SCD not on RASI (reference) between 2010 and 2021 was performed. Inclusion criteria were patients with a baseline eGFR≥15 ml/min/1.73m², ≥3 estimated glomerular filtration rate (eGFR) values, and ≥1 year between first and last eGFR values. The outcomes of interest were the difference in the mean change in eGFR per year (evaluated using linear mixed models), rapid eGFR decline (≥3 ml/min/1.73m²/year), incident stage 5 chronic kidney disease (CKD), and mortality (described using Cox proportional hazard models). Propensity score matching (1:3) adjusted for 16 baseline characteristics. Time-updated RASI use was utilized in all models. All other covariates (demographics, comorbidities, medications, labs) were baseline values.

Results

In total 1,960 SCD patients (476 RASI, 1,484 reference) were identified. After matching, 442 reference patients were used. Matched cohort median follow-up was 4.6 (IQR 2.5-8.3) years with a median of 24 (IQR 10-60) eGFR values, a mean±SD age of 43±16 years, 59% female, and mean baseline eGFR±SD of 97±29 ml/min/1.73m². All results were compared to the matched reference. The adjusted mean eGFR change in RASI users was +0.02 (95% confidence interval [CI] -1.06 to +1.08) ml/min/1.73m²/year. Rapid eGFR decline (hazard ratio [HR] 0.80; 95% CI 0.51-1.25), incident stage 5 CKD (HR, 0.28; 95% CI 0.06-1.21) and mortality (HR, 0.61; 95% CI 0.30-1.25) were not significantly different. Among RASI users only, the adjusted mean eGFR change pre- vs. during-RASI use was -0.13 (95% CI -0.30 to +0.03) ml/min/1.73m²/year.

Conclusion

In the largest observational study to date of adult SCD RAS blockade, RASI use was not associated with adverse or improved long-term kidney outcomes compared to no RASI use. Therefore, if RASI are indicated in SCD, adverse long-term kidney outcomes should not be a concern. Conversely, RASI should not be started solely to slow kidney function decline in SCD.

Funding

• Other NIH Support