Health-Related Quality of Life (HRQoL) in Duchenne Muscular Dystrophy (DMD): Insights From the DMD-QoL Instrument in the United States (US)
Author(s)
Shelagh Szabo, MSc1, Ania Filus, PhD2, Andrew Lloyd, DPhil3, Katherine L. Gooch, PhD2, Melissa Bather, MSc1, Reem Mustafa, MPH1, Susan Iannaccone, MD4, Ivana Audhya, MS2.
1Broadstreet HEOR, Vancouver, BC, Canada, 2Sarepta Therapeutics, Cambridge, MA, USA, 3Acaster Lloyd, London, United Kingdom, 4UT Southwestern, Dallas, TX, USA.
1Broadstreet HEOR, Vancouver, BC, Canada, 2Sarepta Therapeutics, Cambridge, MA, USA, 3Acaster Lloyd, London, United Kingdom, 4UT Southwestern, Dallas, TX, USA.
OBJECTIVES: The DMD-QoL aims to provide an understanding of DMD-specific HRQoL; however, data documenting DMD-QoL changes over time are lacking. The objective was to assess HRQoL impact and evaluate change in DMD-QoL scores over 36 months.
METHODS: Individuals with DMD aged >12 years, or caregivers, completed the DMD-QoL (14-item) at baseline and 36 months. Mean (standard deviation [SD]) DMD-QoL scores (range:14-42) were calculated according to baseline health state (early ambulatory, late ambulatory, early non-ambulatory, and late non-ambulatory) and respondent type (patient- vs caregiver-report). Whether DMD-QoL scores statistically differentiate between health states was assessed using Tukey’s test. Score changes over 36 months were analyzed using linear regression, adjusted for baseline patient age, health state, DMD-QoL score, medication use history, and respondent type.
RESULTS: Among the baseline sample (n=236), mean caregiver-reported DMD-QoL scores ranged from 33.3 (SD=4.0; n=71, early ambulatory) to 27.0 (SD=6.3; n=41, late non-ambulatory); patient-reported scores ranged from 31.8 (SD=5.1; n=11, early ambulatory) to 28.9 (SD=5.9; n=23, late non-ambulatory). When mean scores were compared between health states, caregiver-reported scores significantly differed only between the early and late ambulatory state (-3.3; P=0.028); patient-reported scores did not differ significantly by health state. Over 36 months, ambulatory status deteriorated in 20% of patients by caregiver report (n=100) and in 12.5% of patients by patient report (n=32). For caregiver reports, mean (standard error [SE]) changes over 36 months were -1.8 (0.9; ambulatory at baseline; P=0.050) and -1.6 (0.9; non-ambulatory at baseline; P=0.084). For patient reports, changes were +0.7 (1.1; ambulatory; P=0.530) and +0.9 (1.1; non-ambulatory; P=0.410).
CONCLUSIONS: DMD-QoL scores generally did not statistically differentiate between health states and significant changes over 36 months were not observed despite declining functional status of the sample. DMD-QoL scores suggest HRQoL remains relatively stable despite disease progression and provide insight into the sensitivity of the measure for tracking disease impact over time.
METHODS: Individuals with DMD aged >12 years, or caregivers, completed the DMD-QoL (14-item) at baseline and 36 months. Mean (standard deviation [SD]) DMD-QoL scores (range:14-42) were calculated according to baseline health state (early ambulatory, late ambulatory, early non-ambulatory, and late non-ambulatory) and respondent type (patient- vs caregiver-report). Whether DMD-QoL scores statistically differentiate between health states was assessed using Tukey’s test. Score changes over 36 months were analyzed using linear regression, adjusted for baseline patient age, health state, DMD-QoL score, medication use history, and respondent type.
RESULTS: Among the baseline sample (n=236), mean caregiver-reported DMD-QoL scores ranged from 33.3 (SD=4.0; n=71, early ambulatory) to 27.0 (SD=6.3; n=41, late non-ambulatory); patient-reported scores ranged from 31.8 (SD=5.1; n=11, early ambulatory) to 28.9 (SD=5.9; n=23, late non-ambulatory). When mean scores were compared between health states, caregiver-reported scores significantly differed only between the early and late ambulatory state (-3.3; P=0.028); patient-reported scores did not differ significantly by health state. Over 36 months, ambulatory status deteriorated in 20% of patients by caregiver report (n=100) and in 12.5% of patients by patient report (n=32). For caregiver reports, mean (standard error [SE]) changes over 36 months were -1.8 (0.9; ambulatory at baseline; P=0.050) and -1.6 (0.9; non-ambulatory at baseline; P=0.084). For patient reports, changes were +0.7 (1.1; ambulatory; P=0.530) and +0.9 (1.1; non-ambulatory; P=0.410).
CONCLUSIONS: DMD-QoL scores generally did not statistically differentiate between health states and significant changes over 36 months were not observed despite declining functional status of the sample. DMD-QoL scores suggest HRQoL remains relatively stable despite disease progression and provide insight into the sensitivity of the measure for tracking disease impact over time.
Conference/Value in Health Info
2025-11, ISPOR Europe 2025, Glasgow, Scotland
Value in Health, Volume 28, Issue S2
Code
CO131
Topic
Clinical Outcomes, Patient-Centered Research
Disease
Musculoskeletal Disorders (Arthritis, Bone Disorders, Osteoporosis, Other Musculoskeletal), Pediatrics, Rare & Orphan Diseases