Chalmer T, Baggesen LM, Nørgaard M, Koch-Henriksen N, Magyari M, Sorensen PS; Danish Multiple Sclerosis Group.Early versus later treatment start in multiple sclerosis a register based cohort study. Eur J Neurol. 2018 May 30. doi: 10.1111/ene.13692. [Epub ahead of print]
METHODS:We included all Danish multiple sclerosis (MS) patients treated with DMT through two nationwide population-based MS registries. Patients were categorized as early treated if treatment started within two years after the first MS symptom (n=2,316) and later treated patients if treatment started between two and eight years after clinical onset (n=1,479). We compared time from treatment start to progression to Expanded Disability Status Scale (EDSS) 6 and mortality between cohorts as hazard ratio (HR) using a Cox proportional hazards model with adjustment for stabilized inverse probability of treatment weights. Several sensitivity analyses were conducted.
RESULTS:Median follow-up time of 3,795 patients was 7.0 years (range 0.6-19.5) for the EDSS 6 outcome, and 10.4 years (range 1.2-20.1) for the mortality outcome. Patients with later treatment start showed 42% increased hazard rate of reaching EDSS 6 compared with the early treated patients (HR 1.42; 95% CI 1.18-1.70; p<0.001). When stratified by sex the increased hazard among later treated women persisted (HR 1.53; 95% CI 1.22-1.93; p<0.001), while the HR was lower in men (1.25; 95% CI 0.93-1.69; p=0.15). Mortality was 38% increased in later starters (HR 1.38; 95% CI 0.96-1.99; p=0.08).
CONCLUSION:Patients who started treatment with DMT later had shorter time to reaching EDSS 6 compared with patients who started early, and the delay showed a tendency to shorten time to death. Our results support the use of early treatment.