Renin-angiotensin-aldosterone system inhibition exacerbates anemia in sickle cell disease.

RAAS inhibitors significantly decrease hemoglobin levels in sickle cell disease patients and mouse models, worsening anemia by approximately 0.5 g/dL.

• Why it matters: Anemia is a critical complication in sickle cell disease, and understanding how common treatments like RAAS inhibitors affect it is essential for safe management, especially since their impact in this population was previously unclear.
• What they did: The study analyzed 658 patients and conducted two longitudinal cohorts plus mouse experiments, revealing that RAASi use is independently associated with lower hemoglobin and reduced erythroid activity, with effects reversible by erythropoietin.
• The result: Findings suggest that RAASi therapy exacerbates anemia in sickle cell disease, highlighting the need for close hemoglobin monitoring and cautious use of these drugs in this high-risk group.