Clinical and radiological activity of secondary progressive multiple sclerosis in a population-based cohort.

BACKGROUND AND PURPOSE: Patients with secondary progressive multiple sclerosis (SP MS) and clinical and/or radiological activity could be the more likely to benefit from disease-modifying treatments. To evaluate the proportions each year after progression onset, patients with SP MS onset between 2002 and 2012 from a population-based multiple sclerosis registry in northeastern France were studied. METHODS: Progression onset was first identified by the neurologist's diagnosis (N cohort), and then by using an automated data-driven definition (D cohort). In a given year after onset of progression, clinical activity was defined as at least one relapse, and radiological activity as at least one new T2 and/or gadolinium-enhancing lesion. A multivariate mixed logistic regression was used to assess factors associated with activity during the year. RESULTS: In the N cohort, amongst 833 patients with SP MS with a median follow-up of 8 years, 10.0%-14.8% had at least one relapse in a year during the first 5 years of progression. Including both clinical and radiological activity increased these proportions to 11.9%-23.7%, with the proportion having a magnetic resonance imaging scan in the year ranging from 29.8% to 40.5%. The first year of progression, a young age and a high relapse rate during the 5 years before progression were associated with activity in a given year. The D cohort results confirmed these findings. CONCLUSIONS: A substantial proportion of patients with SP MS present disease activity. Further studies should evaluate the impact of disease-modifying treatments on the disease course of these patients.

Older Age at Multiple Sclerosis Onset Is an Independent Factor of Poor Prognosis: A Population-Based Cohort Study.

BACKGROUND: Late-onset multiple sclerosis (LOMS) frequently features a primary progressive (PP) course, strongly predicting severe disability. In this population-based cohort, we estimated the prognostic role of age at multiple sclerosis (MS) onset, independent of PP course, on disability progression. METHODS: The association of age at disease onset (adult, <50 years [AOMS], vs. late, ≥50 years [LOMS]) and time to Expanded Disability Status Scale (EDSS) score 4 and 6 was estimated by Cox regression modelling. RESULTS: Among 3,597 patients, 245 had LOMS. Relapsing-remitting (RR) disease was less frequent with LOMS than AOMS (51.8 vs. 90.8%, p < 0.0001). PP course, LOMS and male gender predicted short time to EDSS 4 and 6. Worse outcome with LOMS (time to EDSS 4 and 6, HR 2.0 [95% CI 1.7-2.4] and 2.3 [1.9-2.9]) was independent of PP course or male gender. LOMS had greater impact on RR than PP disease (time to EDSS 4 and 6, HR 3.1 [2.3-4.0] and 4.0 [2.9-5.6]). Only LOMS predicted time from EDSS 4 to 6 (p < 0.0001). CONCLUSIONS: Late onset MS was strongly associated with poor prognosis, independent of initial disease course, in predicting the disability progression along time.