Spinal cord area measurements definitive
The total spinal cord area measured at the T9 level in the thoracic spine in 22 people with SPG5 HSP was reduced by 40 to 60% compared with healthy people. Imaging showed no significant brain alterations in the SPG5 group. This measurement is a potential biomarker for clinical trials in SPG5.
Aim to identify potential biomarkers to assess therapeutic efficacy for hereditary spastic paraplegias type 5 (SPG5) by investigating the clinical, cerebrospinal fluid (CSF) and magnetic resonance imaging (MRI) features.
We performed a cross-sectional study to compare SPG5 patients with age- and sex-matched healthy controls who underwent conventional and quantitative MRI techniques of spinal cord (C1-T9) and brain. SPG5 patients also underwent assessment for clinical status and CSF biomarkers (27-hydroxycholesterol, neurofilament light). We identified a set of markers with standardized effect sizes (|t|> 0.5) to estimate sample sizes for disease progression (disease duration > 14 years vs. ≤ 14 years).
Seventeen genetically confirmed SPG5 patients (11 men, 6 women; age range, 13–49 years; median disease duration, 14 years) were enrolled. Compared to healthy controls, the total spinal cord area (SCA) of SPG5 patients was reduced particularly at the thoracic levels (cervical levels: 12–27%; thoracic levels 41–60%). Patients did not show significant alterations of brain signal abnormalities or atrophy relative to controls. A total of 10 surrogate markers were selected and a minimum sample size was achieved with the measurement of SCA on T9 (n = 22) much less that what would be required if using clinical disability assessment (n = 124).
SPG5 patients showed distinct MRI features of spinal cord atrophy without significant brain alterations. Our finding supports the measurements of spinal cord on T9 level as potential endpoint for SPG5 clinical trials.
SOURCE: Orphanet J Rare Dis. 2021 Sep 19;16(1):391. doi: 10.1186/s13023-021-02014-w. PMID: 34538260 © 2021. The Author(s).
Potential markers for sample size estimations in hereditary spastic paraplegia type 5
1. Department of Neurology and Institute of Neurology of First Affiliated Hospital, Institute of Neuroscience, Fujian Medical University, Fuzhou, 350005 China
2. Fujian Key Laboratory of Molecular Neurology, Fujian Medical University, Fuzhou, 350005 China
3. Department of Radiology of First Affiliated Hospital, Fujian Medical University, Fuzhou, 350005 China