Search

Abstract Digital Twin (DT) is a novel concept that may bring a paradigm shift for precision medicine. In this study we demonstrate a DT application for estimating the age of onset of disease-specific brain atrophy in individuals with multiple sclerosis (MS) using brain MRI. We first augmented longitudinal data from a well-fitted spline model derived from a large cross-sectional normal aging data. Then we compared different mixed spline models through both simulated and real-life data and identified the mixed spline model with the best fit. Using the appropriate covariate structure selected from 52 different candidate structures, we augmented the thalamic atrophy trajectory over the lifespan for each individual MS patient and a corresponding hypothetical twin with normal aging. Theoretically, the age at which the brain atrophy trajectory of an MS patient deviates from the trajectory of their hypothetical healthy twin can be considered as the onset of progressive brain tissue loss. With a tenfold cross validation procedure through 1000 bootstrapping samples, we found the onset age of progressive brain tissue loss was, on average, 5–6 years prior to clinical symptom onset. Our novel approach also discovered two clear patterns of patient clusters: earlier onset versus simultaneous onset of brain atrophy.

Summary: Background: Vitamin D insufficiency is associated with risk of multiple sclerosis (MS) relapse; whether supplementation influences prognosis is unknown. The Vitamin D to Ameliorate MS (VIDAMS) trial aimed to determine if high dose (5000 International Units (IU)/day) versus low dose (600 IU/day) vitamin D3, added to daily glatiramer acetate (GA), reduced the risk of clinical relapse in people with established relapsing remitting MS (RRMS) over 96 weeks. Methods: VIDAMS is a randomised, phase 3, double-blind, multi-centre, controlled trial conducted at sixteen neurology clinics in the United States. Participants with MAGNIMS 2010 RRMS, aged 18–50 years, with recent disease activity were eligible to enroll if they had an Expanded Disability Status Scale score ≤4.0; minimum serum 25-hydroxyvitamin D level of 15 ng/ml within 30 days of screening; and average ≤ 1000 IU supplemental vitamin D3 daily in the 90 days prior to screening. Of 203 screened, 183 were eligible for the 30-day run-in to assess GA adherence, after which 172 were randomised 1:1 to low dose vitamin D3 (LDVD) or high dose vitamin D3 (HDVD), and were followed every 12 weeks for 96 weeks. The primary outcome was the proportion that experienced a confirmed relapse and analyses used Kaplan Meier and Cox proportional hazards models. 165 participants returned for ≥1 follow-up visit and were included in the primary and safety analyses; 140 completed a week 96 visit. This study was registered with ClinicalTrials.gov, NCT01490502. Findings: Between March 22, 2012 and March 8, 2019, 172 participants were enrolled and randomised (83 LDVD, 89 HDVD) and differed at baseline only in gender and race: more males received HDVD (31%) than LDVD (16%), and fewer Black participants received HDVD (12%) than LDVD (22%). Among 165 participants with at least one follow-up visit, the proportion experiencing confirmed relapse did not differ between LDVD and HDVD [at 96 weeks: 32% vs. 34%, p = 0.60; hazard ratio (HR): 1.17 (0.67, 2.05), p = 0.57]. There was no hypercalcaemia. Three participants developed nephrolithiasis or ureterolithiasis (1 in the LDVD and 2 in the HDVD group). Two were possibly related to study drug; and one was presumed related to concomitant treatment with topiramate for migraine. Interpretation: VIDAMS provides evidence that HDVD supplementation, added to GA, does not reduce the risk of clinical relapse in people with RRMS. Taken together with the null findings of previous trials, these results suggest that prescribing higher doses of vitamin D for purposes of modifying the RRMS course may not be beneficial. Funding: This investigation was supported by a grant from the National Multiple Sclerosis Society (RG 4407A2/1). Teva Neuroscience, Inc. provided Copaxone (GA) for the duration of the trial.