New natural history of interferon-beta-treated relapsing multiple sclerosis.
OBJECTIVE
To investigate the impact of interferon-beta (IFNbeta) on disease progression in relapsing-remitting multiple sclerosis patients.


METHODS
A cohort of 1,504 relapsing-remitting multiple sclerosis (1,103 IFNbeta-treated and 401 untreated) patients was followed for up to 7 years. Cox proportional hazards regression adjusted for propensity score inverse weighting was used to assess the differences between the two groups for three different clinical end points: secondary progression (SP) and irreversible Expanded Disability Status Scale (EDSS) scores 4 and 6. Times from first visit and from date of birth were used as survival time variables.


RESULTS
The IFNbeta-treated group showed a highly significant reduction in the incidence of SP (hazard ratio [HR], 0.38, 95% confidence interval [CI], 0.24-0.58 for time from 1st visit; HR, 0.36, 95% CI, 0.23-0.56 for time from date of birth; p < 0.0001), EDSS score of 4 (HR, 0.70, 95% CI, 0.53-0.94 for time from first visit; HR, 0.69, 95% CI, 0.52-0.93 for time from date of birth; p < 0.02), and EDSS score of 6 (HR, 0.60, 95% CI, 0.38-0.95 for time from first visit; HR, 0.54, 95% CI, 0.34-0.86 for time from date of birth; p < or = 0.03) when compared with untreated patients. SP and EDSS scores of 4 and 6 were reached with significant delays estimated by times from first visit (3.8, 1.7, and 2.2 years) and from date of birth (8.7, 4.6, and 11.7 years) in favor of treated patients. Sensitivity analysis confirmed findings.


CONCLUSIONS
IFN-beta slows progression in relapsing-remitting multiple sclerosis patients.
Trojano
Maria
M
Department of Neurological and Psychiatric Sciences, University of Bari, Bari, Italy. mtrojano@neurol.uniba.it
Pellegrini
Fabio
F
Fuiani
Aurora
A
Paolicelli
Damiano
D
Zipoli
Valentina
V
Zimatore
Giovanni B
GB
Di Monte
Elisabetta
E
Portaccio
Emilio
E
Lepore
Vito
V
Livrea
Paolo
P
Amato
Maria Pia
MP
D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D016001:Confidence Intervals; D004185:Disability Evaluation; D018450:Disease Progression; D005260:Female; D006801:Humans; D007155:Immunologic Factors / Q000627:therapeutic use*; D016899:Interferon-beta / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D020529:Multiple Sclerosis, Relapsing-Remitting / Q000188:drug therapy* / Q000401:mortality; D016016:Proportional Hazards Models; D016019:Survival Analysis; D016896:Treatment Outcome
D007155:Immunologic Factors; D016899:Interferon-beta