Health-related quality of life in hereditary angioedema patients treated with subcutaneous C1 inhibitor (C1-INH) therapy in Canada

Abstract Background Hereditary angioedema (HAE) therapies have demonstrated improvements in clinical symptoms and health-related quality of life (HR-QoL) in patients with HAE. Specific causes for improvement in HR-QoL have not been sufficiently explored in Canada. Objective To understand patient perspectives on the burden of HAE and their experiences taking subcutaneous plasma-derived C1 inhibitor concentrate (SC-pdC1INH), and to investigate changes in HR-QoL domains which include physical, mental, emotional, functional, social, and medical well-being. Methods A qualitative research design was employed using telephone interviews from May to July 2023 and a quantitative self-administered Angioedema QoL questionnaire (AE-QoL), which has a recall period of 4 weeks. A conceptual map was generated from the interviews that illustrated HR-QoL domains most important to patients. Results This study included 20 patients (50% female; mean age of 51 years; 85% HAE Type 1/2). Patients reported more controlled HAE since starting SC-pdC1INH, with fewer attacks (85%) and even no/nearly no attacks (60%) in the past year. Patients reported emotional benefits (reduced stress/anxiety regarding potential attacks [75%], and increased confidence in managing HAE [95%]). Positive impacts also included increased productivity/less missed days from work/school (40%) and improved physical ability/well-being (50%). The total mean AE-QoL Score was 34 (range 0–87; SD 24.9), indicating a small effect of HAE on HR-QoL in the 4-week pre-interview period. Conclusion Overall, patients on long-term prophylaxis with SC-pdC1INH reported improvements in many HR-QoL domains, but most significantly relief of stress and anxiety associated with HAE, and improvement in social and physical well-being.