ASSESSMENT OF HEALTH-RELATED QUALITY OF LIFE (HRQOL) MEASURES FOR PAEDIATRIC PATIENTS WITH ANAEMIA OF CHRONIC KIDNEY DISEASE (CKD)

Abstract Background and Aims Anaemia is a common complication of CKD in children that is associated with adverse clinical outcomes, including poor physical functioning for patients and lower HRQoL for patients and caregivers.1 Given the subjective nature of the disease, instruments that measure patient- and/or observer-reported outcomes (PROs/ObsROs), by collecting information about symptom severity and HRQoL, could be of value to assess treatment benefit. We determined which aspects of anaemia of CKD and its treatments are important for paediatric patients and their caregivers, and examined which PRO/ObsRO instruments comprehensively capture patients’ and caregivers’ experiences. Method A targeted literature review and database search were performed to find a) qualitative and quantitative studies of symptoms and related health outcomes in paediatric patients with anaemia of CKD; b) related clinical practice guidelines; and c) HRQoL information in product labelling. Study outcomes were used to develop a structured representation of health outcomes concepts and issues (‘conceptual model’) capturing the symptoms, perceptions of treatment and impact on HRQoL of anaemia of CKD, from the perspective of both paediatric patients and their caregivers. PRO and ObsRO instruments were identified from published quantitative studies and ongoing clinical trials, and a selection was then critically assessed to determine their content validity and whether their psychometric properties adequately covered the conceptual model domains. Results The conceptual model captured shortness of breath, fatigue and headaches as the most important symptoms experienced by paediatric patients with anaemia of CKD. Concerns regarding disease management included medical interventions, fear associated with interventions and the need for information about the disease. Disease symptoms and their management impacted seven HRQoL domains, namely physical, emotional and social functioning; activities of daily living; and effects on family, work and caregivers (Figure). The quantitative search of published studies identified 20 unique instruments; of these, the most frequently used was Pediatric Quality of Life Inventory™ (PedsQL) Version 4.0. Ongoing clinical trials used 14 unique instruments, of which only EQ-5D-Y was used in more than one study. Two clinical practice guidelines (National Institute for Health and Care Excellence and Kidney Disease: Improving Global Outcomes) supported measurements of HRQoL, symptoms, patient preferences and school attendance/performance, but they did not advocate use of any specific instruments. No HRQoL product labelling information was identified. Based on the conceptual model, the literature review results and age group coverage, five instruments were selected for critical appraisal: PedsQL, PedsQL Infant Scales, PedsQL Multidimensional Fatigue Scale, PedsQL v3.0 End Stage Renal Disease module, and EQ-5D-Y. Between them, these instruments provided complete coverage of the impact of fatigue and headaches, and partial coverage of the effects on physical functioning, activities of daily living, emotional functioning and social functioning. None of these instruments measured the impact of shortness of breath, and there was no coverage of the consequences for work or the family’s/caregivers’ HRQoL. Conclusion Anaemia of CKD affects many HRQoL domains for paediatric patients and their caregivers. While current PRO/ObsRO instruments partially address these impacts, no single instrument in our assessment measured all symptoms and domains of interest to patients and caregivers. Multiple instruments should be included in clinical studies to capture symptoms and HRQoL important to patients, and adequate measurement of the effects of anaemia on work or the family’s/caregivers’ HRQoL might require development of a new instrument.