The impact of spinal muscular atrophy on daily life activities and the burden for caregivers should be added to tools currently used in clinical practice to measure health-related quality of life, a review suggests.
The study, “A critical review of patient and parent caregiver oriented tools to assess health-related quality of life, activity of daily living and caregiver burden in spinal muscular atrophy,” was published in Neuromuscular Disorders.
Spinal muscular atrophy (SMA) comprises a group of neurodegenerative disorders characterized by the gradual loss of motor neurons — the nerve cells responsible for controlling voluntary muscles — in the spinal cord, leading to muscle weakness and wasting.
“In the last few years there have been exciting advances with revised standards of care and clinical trials using different therapeutic approaches such as antisense oligonucleotides [Spinraza], small molecules or gene therapy [Zolgensma], showing increased life expectancy and functional and respiratory improvements,” the researchers wrote.
“In parallel, there has been an increasing pressure from regulatory authorities and from the SMA community to capture patients and caregivers perspective on the impact of the new treatments on their ‘quality of life,’ ” they added.
However, in neuromuscular disorders such as SMA, there is an additional need to assess the impact of the disease and new therapeutic interventions not only on patients’ health-related quality of life (HRQoL), but also on their ability to perform normal daily tasks, on their level of independence, and on the burden for caregivers.
In the review, researchers summarized the instruments currently used in clinical trials to evaluate the impact of SMA on quality of life and activities of daily living (ADLs) of those living with the disorder, as well as on the burden it places on caregivers.
A literature search in four online databases — Medline, CINAHL, PsycINFO, and Embase — yielded a total of 1,170 potentially relevant studies published between 1980 and 2018. After further screenings, a total of 55 studies were selected to be included in the systematic review. These studies reported the use of 36 instruments that had been used to evaluate the quality of life of patients with SMA or other neuromuscular disorders.
From the 36 instruments identified, six had been specifically developed for SMA: the SMA Health Index (SMA HI), the SMA Independence Scale (SMAIS), the FLASH SURVEY SMA, the Patient Reported Impact of Symptoms in Spinal Muscular Atrophy “PRISM-SMA,” and the International survey 1–2.
SMA HI is a self-reported questionnaire that assesses quality of life in patients older than 12 years; SMAIS measures the amount of assistance required to perform typical daily activities, such as getting dressed or self-feeding; the FLASH SURVEY is a self- and caregiver-reported tool to understand the expectations of current therapeutic developments in type 2 and 3 SMA patients; PRISM-SMA is a self-reported questionnaire that assesses how different symptoms affect adult life in SMA; the International survey 1–2 is a self- and caregiver-reported questionnaire to assess the meaningfulness of functional items and, much like the FLASH SURVEY, the expectations of current therapeutic developments in type 2 and 3 SMA patients.
The remaining 30 instruments had been previously used and at least partially validated in patients with other types of neuromuscular disorders, including SMA.
“Our review showed that very few tools have been specifically developed for SMA. These tools have the advantage that, being disease specific, can better address the specific issues related to the disease and be more sensitive to possible interventions,” the researchers said. “Their number and data on their full validation is however still very limited.”
From the 36 instruments identified, 12 focused on assessing HRQoL, five on activities of daily living, and nine on caregiver burden. Ten assessed both quality of life and activities of daily living.
“The review of these tools confirms a recent trend to develop new tools or modify existing tools to assess activities of daily living in neuromuscular disorders often developed as an integration to the observer rated scales administered in the clinical setting (…) A number of tools focus on caregiver burden in SMA, considering the socio-economic burden more than the psychological impact of the disease,” the researchers wrote.
“Scales assessing activities of daily living and care burden can provide patients and carers perspective on functional changes over time that should be added to the observer rated scales used in clinic,” they said.