Juan F Vázquez-Costa1,2,3, María Branas-Pampillón4, Julita Medina-Cantillo5, Mónica Povedano6, Inmaculada Pitarch-Castellano7, Mercedes López-Lobato8, Joaquín A Fernández-Ramos9, Miguel Lafuente-Hidalgo10, Ricard Rojas-García11, José M Caballero-Caballero12, Ignacio Málaga13, Jesús Eirís-Puñal14, Mencía De Lemus15, María G Cattinari15, Rosana Cabello-Moruno2, Paola Díaz-Abós2, Victoria Sánchez-Menéndez2, Pablo Rebollo16, Jorge Maurino2, Marcos Madruga-Garrido17. 1. Neuromuscular Unit, Department of Neurology, Hospital Universitari I Politècnic La Fe, Valencia, Spain. 2. Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Valencia, Spain. 3. Department of Medicine, University of Valencia, Valencia, Spain. 4. Medical Department, Roche Farma, Ribera del Loira, 50, 28042), Madrid, Spain. maria.branas_pampillon@roche.com. 5. Rehabilitation and Physical Unit Department, Hospital Sant Joan de Deu, Barcelona, Spain. 6. Department of Neurology, IDIBELL, Hospital de Bellvitge, Barcelona, Spain. 7. Child Neurology Unit, Department of Pediatrics, Hospital Universitari I Politècnic La Fe, Valencia, Spain. 8. Neuromuscular Research Unit, Department of Pediatric Neurology, Hospital Universitario Virgen del Rocío, Universidad de Sevilla, Seville, Spain. 9. Child Neurology Unit, Department of Pediatrics, Hospital Universitario Reina Sofía, Córdoba, Spain. 10. Child Neurology Unit, Department of Pediatrics, Hospital Universitario Miguel Servet, Saragossa, Spain. 11. Neuromuscular Diseases Unit, Department of Neurology, Hospital de La Santa Creu I Sant Pau, Barcelona, Spain. 12. Department of Child Neurology, Hospital Universitario La Paz, Madrid, Spain. 13. Child Neurology Unit, Hospital Universitario Central de Asturias, Oviedo, Spain. 14. Department of Pediatric Neurology, Complejo Hospitalario Universitario de Santiago, Santiago de Compostela, Spain. 15. Fundacion Atrofia Muscular Espinal España (FundAME), Madrid, Spain. 16. IQVIA, Madrid, Spain. 17. Hospital Viamed Santa Ángela de La Cruz, Seville, Spain.
Abstract
INTRODUCTION: Outcome measures traditionally used in spinal muscular atrophy (SMA) clinical trials are inadequate to assess the full range of disease severity. The aim of this study was to assess the psychometric properties of a set of existing questionnaires and new items, gathering information on the impact of SMA from the patient and caregiver perspectives. METHODS: This was a multicenter, prospective, noninterventional study including patients with a confirmed diagnosis of 5q-autosomal-recessive SMA aged 8 years and above, or their parents (if aged between 2 and 8 years). The set of outcome measurements included the SMA Independence Scale (SMAIS) patient and caregiver versions, the Neuro-QoL Fatigue Computer Adaptive Test (CAT), the Neuro-QoL Pain Short Form-Pediatric Pain, the PROMIS adult Pain Interference CAT, and new items developed by Fundación Atrofia Muscular España: perceived fatigability, breathing and voice, sleep and rest, and vulnerability. Reliability, construct validity, discriminant validity, and sensitivity to change (4 months from baseline) were measured. RESULTS: A total of 113 patients were included (59.3% 2-17 years old, 59.3% male, and 50.4% with SMA type II). Patients required moderate assistance [mean patient and caregiver SMAIS (SD) scores were 31.1 (12.8) and 7.6 (11.1), respectively]. Perceived fatigability was the most impacted domain, followed by vulnerability. Cronbach's alpha coefficient for perceived fatigability, breathing and voice, and vulnerability total scores were 0.92, 0.88, and 0.85, respectively. The exploratory factor analysis identified the main factors considered in the design, except in the sleep and rest domain. All questionnaires were able to discriminate between the Clinical Global Impression-Severity scores and SMA types. Sensitivity to change was only found for the SMAIS caregiver version and vulnerability items. CONCLUSIONS: This set of outcome measures showed adequate reliability, construct validity, and discriminant validity and may constitute a valuable option to measure symptom severity in patients with SMA.
INTRODUCTION: Outcome measures traditionally used in spinal muscular atrophy (SMA) clinical trials are inadequate to assess the full range of disease severity. The aim of this study was to assess the psychometric properties of a set of existing questionnaires and new items, gathering information on the impact of SMA from the patient and caregiver perspectives. METHODS: This was a multicenter, prospective, noninterventional study including patients with a confirmed diagnosis of 5q-autosomal-recessive SMA aged 8 years and above, or their parents (if aged between 2 and 8 years). The set of outcome measurements included the SMA Independence Scale (SMAIS) patient and caregiver versions, the Neuro-QoL Fatigue Computer Adaptive Test (CAT), the Neuro-QoL Pain Short Form-Pediatric Pain, the PROMIS adult Pain Interference CAT, and new items developed by Fundación Atrofia Muscular España: perceived fatigability, breathing and voice, sleep and rest, and vulnerability. Reliability, construct validity, discriminant validity, and sensitivity to change (4 months from baseline) were measured. RESULTS: A total of 113 patients were included (59.3% 2-17 years old, 59.3% male, and 50.4% with SMA type II). Patients required moderate assistance [mean patient and caregiver SMAIS (SD) scores were 31.1 (12.8) and 7.6 (11.1), respectively]. Perceived fatigability was the most impacted domain, followed by vulnerability. Cronbach's alpha coefficient for perceived fatigability, breathing and voice, and vulnerability total scores were 0.92, 0.88, and 0.85, respectively. The exploratory factor analysis identified the main factors considered in the design, except in the sleep and rest domain. All questionnaires were able to discriminate between the Clinical Global Impression-Severity scores and SMA types. Sensitivity to change was only found for the SMAIS caregiver version and vulnerability items. CONCLUSIONS: This set of outcome measures showed adequate reliability, construct validity, and discriminant validity and may constitute a valuable option to measure symptom severity in patients with SMA.