OBJECTIVES: Health-state utilities are proxies for patient quality-of-life and are important inputs for health economic models to assess the impact of new medical technologies and guide healthcare decision-making. This study aimed to characterize the health utility of “attacks” associated with hereditary angioedema (HAE), a rare and potentially life-threatening genetic disease characterized by recurrent episodes of swelling.

METHODS: We conducted a systematic literature review (SLR) on economic outcomes, including utility values, among individuals with HAE, in accordance with PRISMA guidelines. We searched multiple databases, including PubMed, Embase, and health technology assessment websites. Article inclusion was limited to English peer-review and grey literature published between January 1, 2007 – July 1, 2022. Two independent reviewers assessed literature eligibility and abstracted data.

RESULTS: We identified 66 studies. The majority of studies were observational (64%) and peer-reviewed (58%), and the most common study location was the United States (42%). Among these 66 studies, 15 (23%) reported on HAE utilities, with mean non-attack utility ranging from 0.72 – 0.83 and mean utility during an attack ranging from 0.44 – 0.51. An inverse relationship between utility and attack severity was observed, with mean weights of 0.61, 0.47, and 0.08 for mild, moderate, and severe attacks, respectively. Utilities also varied by attack location, with the lowest mean utility values observed for abdominal and laryngeal attacks (0.35 and 0.13, respectively). Modeling of on-demand HAE therapies suggest that treatment may improve attack-associated disutility to non-attack levels (0.75 – 0.80) that fall within population norms.

CONCLUSIONS: The burden of HAE attacks translates into substantial health status disutility. While treatment with on-demand therapy attenuates attack-associated disutility, increasing attack severity substantially impacts patient utility. New therapeutics that facilitate early treatment, thereby mitigating attack severity and hastening attack resolution, are needed to yield the greatest patient benefit.