Genetic and Social Determinants of Renin-Angiotensin-Aldosterone System Inhibitor-Induced Angioedema: A Precision Medicine Health Equity Study

Angioedema is a life-threatening adverse drug reaction associated with renin-angiotensin-aldosterone system (RAAS) inhibitors, characterized by localized swelling in the deep layers of the skin. Well-established evidence indicates an up to fivefold higher incidence of RAAS inhibitor-induced angioedema in self-identified Black patients compared to White patients. The mechanisms underlying this health disparity remain poorly understood and are often attributed to race, a poor proxy for interindividual genetic similarity and social stressors. Here, we investigate the genetic and social determinants of RAAS inhibitor-induced angioedema as well as the etiology of this racial difference. In particular, we (1) discovered <i>OTULINL</i> and <i>CRABP1</i> as novel loci for RAAS inhibitor-induced angioedema, (2) confirmed the importance of bradykinin for this adverse drug reaction, (3) reported the first significant genome-wide association in self-identified Black participants, (4) identified alcohol use as an important social determinant, (5) demonstrated the strong role of variants enriched in 1000 Genomes African superpopulation-like genomes as the driver of racially differential angioedema risk, and (6) demonstrated the combined role of polygenic effect size and allele frequency differences in explaining these racial differences. Our results suggest that a clinical precision medicine tool may more precisely predict for whom RAAS inhibitors should be avoided (to prevent angioedema) compared to using race. These findings ultimately underscore the value of an evidence-based approach to removing race from treatment guidelines, which carries less potential harm than other removal strategies.