{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,7]],"date-time":"2026-10-07T16:10:35Z","timestamp":1791389435611,"version":"4.3.3"},"reference-count":21,"publisher":"Springer Science and Business Media LLC","issue":"3","license":[{"start":{"date-parts":[[2026,3,1]],"date-time":"2026-03-01T00:00:00Z","timestamp":1772323200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2026,3,6]],"date-time":"2026-03-06T00:00:00Z","timestamp":1772755200000},"content-version":"vor","delay-in-days":5,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"name":"Health Holland, Top Sector Life Sciences and Health","award":["Grant No. LSHM16060-SGF"],"award-info":[{"award-number":["Grant No. LSHM16060-SGF"]}]},{"DOI":"10.13039\/501100003000","name":"Stichting MS Research","doi-asserted-by":"publisher","award":["Grant No. 16-946 MS"],"award-info":[{"award-number":["Grant No. 16-946 MS"]}],"id":[{"id":"10.13039\/501100003000","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100005614","name":"Biogen","doi-asserted-by":"publisher","award":["Unrestricted funding"],"award-info":[{"award-number":["Unrestricted funding"]}],"id":[{"id":"10.13039\/100005614","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["J Neurol"],"published-print":{"date-parts":[[2026,3]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Digital monitoring shows promise for detecting disease activity in people with relapsing\u2013remitting multiple sclerosis (PwRRMS). Here, we study associations between digital biomarkers for cognition and walking ability and radiological disease activity.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>In a prospective, 1-year cohort study, PwRRMS performed the smartphone-based symbol digit modalities test (sSDMT) and 2-min walk test (s2MWT) on weekly basis. MRIs and the clinical SDMT (cSDMT), expanded disability status scale (EDSS), timed 25-foot walk (T25FW) and nine-hole peg test (NHPT) were collected at baseline and every 3\u00a0months. Associations were determined using logistic generalized estimating equations. For the digital measures, associations were also analyzed using a hybrid model and were repeated with values from 6\u00a0weeks before and after MRI.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      We included 57 PwRRMS. The sSDMT was negatively associated with contrast-enhancing lesions (CELs) (OR\n                      <jats:sub>overall<\/jats:sub>\n                      1.80, 95% CI 1.12\u20132.91), predominantly caused by variation within individuals (OR\n                      <jats:sub>within-subjects<\/jats:sub>\n                      4.37, 2.05\u20139.33), with a similar relation using sSDMT values 6\u00a0weeks prior to MRI (OR\n                      <jats:sub>overall<\/jats:sub>\n                      : 1.92, 0.947\u20133.90, OR\n                      <jats:sub>within-subjects<\/jats:sub>\n                      : 13.7, 1.74\u2013107). The negative association between s2MWT and CELs (OR\n                      <jats:sub>overall<\/jats:sub>\n                      1.20, 1.04\u20131.38) was caused equally by variation within and between individuals. All clinical measures were negatively associated with CELs: T25FW (OR\n                      <jats:sub>overall<\/jats:sub>\n                      2.23, 1.50\u20133.32), EDSS (OR\n                      <jats:sub>overall<\/jats:sub>\n                      1.49, 0.932\u20132.39), cSDMT (OR\n                      <jats:sub>overall<\/jats:sub>\n                      1.20, 1.02\u20131.42) and NHPT (OR\n                      <jats:sub>overall<\/jats:sub>\n                      1.15, 1.04\u20131.27).\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Discussion<\/jats:title>\n                    <jats:p>Digital biomarkers show to be capable of measuring changes in individuals when inflammation is detectable on MRI, with the sSDMT additionally capturing changes 6\u00a0weeks prior to the MRI, suggesting that early identification of inflammation using these biomarkers may be possible.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1007\/s00415-026-13685-5","type":"journal-article","created":{"date-parts":[[2026,3,6]],"date-time":"2026-03-06T16:00:56Z","timestamp":1772812856000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Digital monitoring of disease activity in relapsing\u2013remitting multiple sclerosis"],"prefix":"10.1007","volume":"273","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4735-539X","authenticated-orcid":false,"given":"P. 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M.","family":"Heskes","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"V.","family":"de Groot","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"B. M. J.","family":"Uitdehaag","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"B. A.","family":"de Jong","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"J. W. R.","family":"Twisk","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"E. M. 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Molenaar has nothing to disclose, D.J. de Jong has nothing to disclose, S.N. Hof has nothing to disclose, P. van Oirschot was an employee of Sherpa B.V. (manufacturer of the MS sherpa app), I.G. Bucur is funded by Radboud Healthy Data, K.H. Lam has nothing to disclose, B. Moraal has nothing to disclose, T.M. Heskes has nothing to disclose, V. de Groot has nothing to disclose, B.M.J. Uitdehaag has received research support and\/or consultancy fees from Biogen Idec, Genzyme, Merck, Serono, Novartis, Roche, Teva and Immunic Therapeutics, B.A. de Jong has received grants from Dutch MS Research Foundation, National MS Foundation and Dutch MS Society and is member of the medical advisory board of the Dutch MS Society and chair of the committee of the Dutch National MS registration of the Netherlands Society of Neurology, J. Twisk has nothing to disclose, E.M.M. Strijbis has speaker relations with Merck and Novartis (all payments to institution), J. Killestein has received consulting fees for F. Hoffmann-La Roche, Biogen, Teva, Merck, Novartis and Sanofi\/Genzyme (payments to institution); reports speaker relationships with F. Hoffmann-La Roche, Biogen, Teva, Merck, Novartis and Sanofi\/Genzyme (payments to institution); adjudication committee of MS clinical trials of Immunic (payments to institution).","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Conflicts of interest"}},{"value":"Use of data from the Dutch-MSR was approved by the medical research ethics committee of the Amsterdam UMC (reference 2021.0506).","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethical approval"}},{"value":"Written informed consent from all participants in this study was collected prior to inclusion.","order":4,"name":"Ethics","group":{"name":"EthicsHeading","label":"Consent to participate"}}],"article-number":"186"}}