OBJECTIVES
The objectives of this study are to investigate 1). which HRQoL outcomes are most significant to patients and caregivers in SMA Types 2 and 3; 2). which instruments are used to assess and measure these outcomes; and 3). which HRQoL instruments are validated and endorsed in SMA Types 2 and 3.
METHODS
A systematic literature review was conducted in PubMed using terms related to SMA Types 2 and 3 and HRQoL, focused on original research studies published from 2015 through October 2024. Two independent reviewers applied eligibility criteria and extracted data on all HRQoL measures.
RESULTS
Of the 901 records screened, 23 studies utilizing 13 different HRQoL instruments met eligibility criteria. The most commonly reported outcome was fatigue. The PedsQL 3.0 Neuromuscular Module (NMM) was the most commonly used instrument, but only one study assessed its validity. Most studies had a follow-up period of <1 year, and had ≤35 participants. Four studies utilized the validated Spinal Muscular Atrophy Health Index (SMA-HI) developed specifically for SMA. No studies used the SMA Caregiver Reported Health Index.
CONCLUSIONS
Few HRQoL measures are specifically designed and validated for SMA types 2 and 3. In addition, there is no consensus on a standard HRQoL tool in this patient population accentuating the need for additional research with larger cohorts and extended durations. Unlike generic PRO tools, the initial application of the SMA-HI underscores the importance of utilizing SMA-specific instruments that are designed to be sensitive to change over time, making them particularly valuable for assessing the impact of SMA treatments. Further research is needed to better understand which outcomes are most valued by patients and caregivers, and to understand the potential need for development of new HRQoL instruments tailored to these SMA subtypes.