Health-related quality of life in patients with diverse rare diseases: An online survey

Purpose: Rare diseases substantially contribute to population morbidity and mortality. Understanding rare disease health-related quality of life (HRQL) is essential for evaluating platform-based interventions that aim to tackle multiple rare diseases at a time. However, most HRQL studies focus on single or select group of rare diseases, often in a single country. Our study aimed to identify patient- and disease-specific correlates of HRQL across diverse rare diseases. Methods: We conducted an international online survey of rare disease patients and caregiver proxies affected by a systematically identified sample of rare diseases. We calculated EQ-5D scores and conducted multivariate linear regression to examine sociodemographic and disease predictors of EQ-5D-5L visual analog scale (VAS) and utility scores (United States only). Results: A total of 1053 individuals affected by 103 different rare diseases participated, including 660 patients and 393 caregiver proxies. Disability status and disease prevalence correlated with poorer HRQL across models (P < .05). Increased pain and decreased ability to perform usual activities also correlated with lower VAS for both adult patients and caregiver proxies (P < .05). Being unemployed approached significance as a correlate of both lower caregiver proxy VAS and lower patient utility scores. Conclusion: Our results suggest that across rare diseases, lower HRQL is associated with a reduced rare disease prevalence and disability status, among other predictors. Understanding the key correlates of HRQL is essential for developing interventions for improving health care delivery and quality of life for rare disease patients and families.