Do patients' and referral centers' characteristics influence multiple sclerosis phenotypes? Results from the Italian multiple sclerosis and related disorders register.

BACKGROUND: Multiple sclerosis (MS) is characterized by phenotypical heterogeneity, partly resulting from demographic and environmental risk factors. Socio-economic factors and the characteristics of local MS facilities might also play a part. METHODS: This study included patients with a confirmed MS diagnosis enrolled in the Italian MS and Related Disorders Register in 2000-2021. Patients at first visit were classified as having a clinically isolated syndrome (CIS), relapsing-remitting (RR), primary progressive (PP), progressive-relapsing (PR), or secondary progressive MS (SP). Demographic and clinical characteristics were analyzed, with centers' characteristics, geographic macro-areas, and Deprivation Index. We computed the odds ratios (OR) for CIS, PP/PR, and SP phenotypes, compared to the RR, using multivariate, multinomial, mixed effects logistic regression models. RESULTS: In all 35,243 patients from 106 centers were included. The OR of presenting more advanced MS phenotypes than the RR phenotype at first visit significantly diminished in relation to calendar period. Females were at a significantly lower risk of a PP/PR or SP phenotype. Older age was associated with CIS, PP/PR, and SP. The risk of a longer interval between disease onset and first visit was lower for the CIS phenotype, but higher for PP/PR and SP. The probability of SP at first visit was greater in the South of Italy. DISCUSSION: Differences in the phenotype of MS patients first seen in Italian centers can be only partly explained by differences in the centers' characteristics. The demographic and socio-economic characteristics of MS patients seem to be the main determinants of the phenotypes at first referral.

Natalizumab treatment in multiple sclerosis patients: a multicenter experience in clinical practice in Italy.

We evaluated efficacy of natalizumab in relapsing-remitting multiple sclerosis patients in a clinical practice setting. We report data on the first consecutive 343 patients receiving natalizumab in 12 multiple sclerosis (MS) Italian centers enrolled between April 2007 and November 2010. The main efficacy endpoints were the proportion of patients free from relapses, disease progression, combined clinical activity, defined as presence of relapse or disease progression, from MRI activity, and from any disease activity defined as the absence of any single or combined activity. At the end of follow-up, the cumulative proportion of patients free from relapses was 68%; the proportion of patients free from Expanded Disability Status Scale (EDSS) progression was 93%; the proportion of patients free from combined clinical activity was 65%; the proportion of patients free from MRI activity was 77%; and the proportion of patients free from any disease activity was 53%. Natalizumab was effective in reducing clinical and neuroradiological disease activity. Its effectiveness in clinical practice is higher than that reported in pivotal trials and was maintained over time.