Cognitive impairment in Chinese adult patients with type III spinal muscular atrophy without disease-modifying treatment

Impact of Nusinersen Treatment on the Independence and Mental Health of School-Aged Patients With Spinal Muscular Atrophy

BACKGROUND

Emerging disease-modifying therapies for spinal muscular atrophy (SMA) have altered patients' mental health and daily functioning. This longitudinal study evaluated nusinersen's effects on independence and mental health in school-age SMA patients.

METHODS

Thirty-one SMA type 2/3 patients from a pediatric hospital were assessed using the SMA Independence Scale-Upper Limb Module (SMAIS-ULM), Screen for Child Anxiety-Related Emotional Disorders (SCARED), and Depression Self-Rating Scale for Children (DSRSC). Motor function was measured via Hammersmith Functional Motor Scale-Expanded (HFMSE) and Revised Upper Limb Module (RULM), with correlations analyzed.

RESULTS

Median treatment initiation age was 9.19 (8.73-11.90) years. After 14 months, SMAIS-ULM scores improved significantly (P < 0.01), while anxiety/depression rates declined (P < 0.01). Higher HFMSE scores correlated with better independence (P < 0.01) and reduced anxiety/depression (P < 0.01). Similarly, higher RULM scores predicted greater independence (P < 0.01) and lower anxiety (P < 0.05).

CONCLUSIONS

Nusinersen therapy enhances independence and mental health in school-age SMA patients, supported by patient-reported outcomes. These findings underscore its multifaceted therapeutic benefits.

Reduced white matter integrity and disrupted brain network in children with type 2 and 3 spinal muscular atrophy

BACKGROUND

Spinal muscular atrophy (SMA) is caused by reduced expression of survival motor neuron (SMN) protein. Previous studies indicated SMA causes not only lower motor neuron degeneration but also extensive brain involvement. This study aimed to investigate the changes of brain white matter and structural network using diffusion tensor imaging (DTI) in children with type 2 and 3 SMA.

METHODS

Forty-two type 2 and 3 pediatric SMA patients and 42 age- and gender-matched healthy controls (HC) were prospectively enrolled in this study. The tract-based spatial statistics (TBSS) was used to assess white matter integrity and the structural network properties were calculated based on DTI white matter fiber tracking and the graph theory approach. A partial correlation was performed to explore the relationship between white matter parameters and clinical characteristics.

RESULTS

In total, 42 patients (mean age, 10.86 ± 4.07 years; 23 men) were included. TBSS analysis revealed widespread white matter changes in SMA patients. The SMA patients showed changes in multiple small-world and network efficiency parameters. Compared to the HC group, SMA showed increased characteristic path length (Lp), normalized clustering coefficient (γ), small-world characteristic (σ), and decreased global efficiency (Eglob) (all p < 0.05). In the node properties, right supramarginal gyrus, right orbital part of superior frontal gyrus, right supplementary motor area, and left median cingulate and paracingulate gyri changed in SMA patients. A decreased axial diffusivity (AD) value was associated with lower Hammersmith Functional Motor Scale-Expanded scores (r = 0.45, p = 0.02), which means that the symptoms of SMA patients are more severe.

CONCLUSIONS

This study found white matter and DTI-based brain network abnormalities in SMA patients, suggesting SMN protein deficiency may affect white matter development.

Cognitive impairment in children with 5q-associated spinal muscular atrophy type 1: two case reports and the review of the literature

Spinal muscular atrophy (SMA) is an autosomal recessive disease caused by mutations in the survival motor neuron 1 (SMN1) gene on chromosome 5, leading to the degeneration of lower motor neurons. There are few studies on cognitive impairment comorbid with SMA. Here, we report two cases of severe cognitive impairment in Chinese children with SMA type 1, marking the first such reports in this demographic. We propose that severe cognitive dysfunction may be a comorbidity of SMA. Clinicians should consider SMA in patients presenting with severe muscle weakness and atrophy accompanied by cognitive impairments, to avoid misdiagnosis and oversight.

Exploring variability in cognitive functioning in patients with spinal muscular atrophy: a scoping review

The cognitive functioning of individuals with spinal muscular atrophy (SMA) is not well understood, prompting a call for more research to better grasp cognitive involvement in SMA. This study aims to explore recent findings regarding cognitive outcomes in SMA patients, including correlations between clinical features and cognitive abilities. The investigation seeks to identify commonly used measures for assessing cognitive function in this patient population. A scoping review following the Joanna Briggs Institute methodology examined literature until December 2023. Two databases were searched along with relevant article references using specific terms such as "spinal muscular atrophy," "SMA," "cognitive," "abilities," "functions," "intellective," or "intellectual." Screening focused on titles and abstracts from English language peer-reviewed journals. After the initial research, 1452 articles were identified. Subsequent screening and selection led to the inclusion of 13 articles in the review. Among these studies, four indicated a cognitive trend within the normal range for SMA patients. In four other studies, the majority of patients fell within the normal range. However, smaller proportions were observed to be either above or below the norm compared to the controls. Three studies reported noted cognitive performance below the average, while two showed above-average scores. The scoping review suggests that most SMA patients have cognitive abilities similar to the general population, with types II and III showing even lesser impact. However, certain cognitive domains may be affected in type I patients, highlighting the need for further research to fully understand cognitive involvement in SMA.