Article Text
Abstract
Background The spinal cord (SC) is a preferential target of multiple sclerosis (MS) damage highly relevant towards disability. Differential impact of such damage could be due to the initial amount of SC tissue, as described for the brain parenchyma (brain reserve concept). We aimed to test the existence of SC reserve by using spinal canal area (SCaA) as a proxy.
Methods Brain sagittal three-dimensional T1-weighted scans covering down to C5 level were acquired in 2930 people with MS and 43 healthy controls (HCs) in a cross-sectional, multicentre study. SC area (SCA) and SCaA were obtained with the Spinal Cord Toolbox. Demographical data and patient-derived disability scores were obtained. SC parameters were compared between groups with age-adjusted and sex-adjusted linear regression models. The main outcome of the study, the existence of an association between SCaA and Patient Determined Disease Steps, was tested with scaled linear models.
Results 1747 persons with MS (mean age: 46.35 years; 73.2% female) and 42 HCs (mean age: 45.56 years; 78.6% female) were analysed after exclusion of post-processing errors and application of quality criteria. SCA (60.41 mm2 vs 65.02 mm2, p<0.001) was lower in people with MS compared with HC; no differences in SCaA were observed (213.24 mm2 vs 212.61 mm2, p=0.125). Adjusted scaled linear models showed that a larger SCaA was significantly associated with lower scores on Patient Determined Disease Steps (beta coefficient: −0.12, p=0.0124) independently of spinal cord atrophy, brain T2 lesion volume, age and sex.
Conclusions A larger SCaA may be protective against disability in MS, possibly supporting the existence of SC reserve.
- multiple sclerosis
- image analysis
Data availability statement
Data are available upon reasonable request. Data to support the findings of this study are currently accessible to MS PATHS Network investigators and collaborators. These data will be made available to qualified researchers on request.
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Data availability statement
Data are available upon reasonable request. Data to support the findings of this study are currently accessible to MS PATHS Network investigators and collaborators. These data will be made available to qualified researchers on request.
Footnotes
Twitter @J_SastreGarriga
Contributors Conception and design of the study: JS-G, AR, MT, DP. Acquisition and analysis of data: JS-G, AR, AG-V, PC-M, CA, MT, XM, DP. Drafting a significant portion of the manuscript or figures (i.e., a substantial contribution beyond copy editing and approval of the final draft, which is expected of all authors): JS-G, AR, AG-V, PC-M, AV-J, CA, MT, XM, DP. Guarantor of the study: JSG.
Funding The authors thank the “Ajuts per donar Suport als Grups de Recerca de Catalunya”, sponsored by the “Agència de Gestió d’Ajuts Universitaris i de Recerca” (AGAUR), Generalitat de Catalunya, Spain (grant number: 2017SGR527). The MS PATHS network is funded by BIOGEN Inc. As stated in the MS PATHS network regulation, BIOGEN has no role in writing or editing publications unless one of the coauthors is a Biogen employee. This work was partly supported by the ‘Fondo de Investigación Sanitaria’ (FIS) of the Ministry of Economy and Competitiveness of Spain (grant PI18/00823 awarded to DP).
Competing interests JS-G declares fees from Sanofi, Biogen, Celgene, Merck, Biopass, Novartis and Roche, outside the submitted work. AR serves on scientific advisory boards for Novartis, Sanofi-Genzyme, Synthetic MR, TensorMedical, Roche, Biogen and OLEA Medical, and has received speaker honoraria from Bayer, Sanofi-Genzyme, Merck-Serono, Teva Pharmaceutical Industries Ltd, Novartis, Roche and Biogen. He is also member of the editorial board of Neurology and Neuroradiology, and member of the executive committee of the International Society of Radiology (ISR) and of MAGNIMS. AG-V has nothing to disclose. PC-M has nothing to disclose. MA has nothing to disclose. AV-J has received support has received support for contracts Juan Rodes (JR16/00024) and from Fondo de Investigación en Salud (PI17/02162) from Instituto de Salud Carlos III, Spain, and has engaged in consulting and/or participated as speaker in events organised by Roche, Novartis, Merck and Sanofi. CA declares that she has no conflict of interest. MT reports personal fees from Almirall, Bayer Healthcare, Biogen Idec, Merck-Serono, Novartis, Roche, Viela-Bio, Sanofi–Genzyme and Teva, grants from Sanofi-Genzyme, and other competing interests related to Biogen Idec, outside the submitted work. XMo reports personal fees from and other competing interests related to Actelion, Alexion, Biogen, Celgene, EMD Serono, Genzyme, Hoffmann-La Roche, Immunic, Medday, Merck, Mylan, Nervgen, Novartis, Sanofi-Genzyme, Teva Pharmaceutical and TG Therapeutics and grants received through the institutions from AbbVie, Biogen, Hoffmann-La Roche, Medday, Merck, Novartis, Sanofi-Genzyme and Teva Pharmaceutical, outside the submitted work. DP reports personal fees from Novartis and Sanofi-Genzyme, outside the submitted work.
Provenance and peer review Not commissioned; externally peer reviewed.
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