Health-related quality of life and patient-reported outcome measurements in patients with cystinosis

Nephropathic cystinosis is a rare autosomal recessive lysosomal storage disorder. With the availability of treatment and renal replacement therapy, nephropathic cystinosis has evolved from an early fatal disease to a chronic, progressive disorder with potentially high impairment. We aim to review the literature on the health-related quality of life and identify appropriate patient-reported outcome measurements to assess the health-related quality of life of patients with cystinosis. For this review, we conducted a literature search in PubMed and Web of Science in September 2021. Inclusion and exclusion criteria for the selection of articles were defined a priori. We identified 668 unique articles through the search and screened them based on title and abstract. The full texts of 27 articles were assessed. Finally, we included five articles (published between 2009 and 2020) describing the health-related quality of life in patients with cystinosis. All studies, apart from one, were conducted in the United States, and no condition-specific measurement was used. Patients with cystinosis reported a lower health-related quality of life (for certain dimensions) than healthy subjects. Few published studies address the health-related quality of life of patients with cystinosis. Such data must be collected standardized and follow the FAIR (Findable, Accessible, Interoperable, and Reusable) principles. To gain a comprehensive understanding of the impact of this disorder on health-related quality of life, it is necessary to use generic and condition-specific instruments to measure this, preferably in large samples from longitudinal studies. A cystinosis-specific instrument for measuring health-related quality of life has yet to be developed.