Detailed updated records from Multiple Sclerosis (MS) patient cohorts are crucial to obtain information on disease course and prognosis.
To characterize the natural history of MS in a cohort from a Portuguese tertiary centre, comparing patients’ characteristics according to the first appointment date throughout 10-year spans (1987-1996; 1997-2006; 2007-2016).
In this longitudinal retrospective study we collected data about demography, diagnosis (date, EDSS, subtype), follow-up (duration, EDSS, subtype), relapses (initial symptoms, annualized relapse rate-ARR) and disease-modifying therapies (DMT). We conducted descriptive analysis to characterize the cohort and compared data between the three decades using Chi-square test, ANOVA and Kruskal-Wallis test.
548 adult patients with relapsing-remitting MS were included, 73% female. Mean age at diagnosis was 34.0 years and mean disease duration 14.7 years. 5.7% of all patients had family history of MS. Eighteen patients had died. No significant differences were found regarding gender and age at diagnosis in patients from the 3 subgroups. The most common presenting relapses were supratentorial and spinal cord related. The median number of relapses between first and last appointment was 3, significantly higher in subgroups 87-96 and 97-06, although the ARR was significantly higher in the subgroup 07-16. The baseline EDSS was significantly higher in 87-96 decade and the percentage of patients achieving EDSS 3.0 and 6.0 significantly decreased since first decade. The mean time between EDSS 3.0 and 6.0 was 4.28 years, without significant differences in the 3 decades. The percentage of patients who converted to secondary progressive (SP) disease was significantly higher in 87-96 decade; the mean time to reach SP was 15.5 years, similar in all decades. The majority of patients started treatment with a first line DMT. The number of patients under a second line drug was higher for those included in the decades 97-06 and 07-16. Median time from diagnosis to first treatment was considerably higher for patients with first appointment in the 87-96 decade.
We document the natural history of MS in 3 decades, including 87-96 where DMT were not yet available, and found that patient’s demography remains similar. The higher ARR in last decade may reflect a better awareness of disease monitoring and differences in disability progression may be due to the impact of increasing DMTs.