Real-life impact of early interferon beta therapy in relapsing multiple sclerosis.
OBJECTIVE
Recent findings support greater efficacy of early vs. delayed interferon beta (IFNbeta) treatment in patients with a first clinical event suggestive of multiple sclerosis (MS). We aimed to evaluate the effectiveness of early IFNbeta treatment in definite relapsing-remitting MS (RRMS) and to assess the optimal time to initiate IFNbeta treatment with regard to the greatest benefits on disability progression.


METHODS
A cohort of 2,570 IFNbeta-treated RRMS patients was prospectively followed for up to 7 years in 15 Italian MS Centers. A Cox proportional hazards regression model adjusted for propensity score (PS) quintiles was used to assess differences between groups of patients with early vs. delayed IFNbeta treatment on risk of reaching a 1-point progression in the Expanded Disability Status Scale (EDSS) score, and the EDSS 4.0 and 6.0 milestones. A set of PS-adjusted Cox hazards regression models were calculated according to different times of treatment initiation (within 1 year up to within 5 years from disease onset). A sensitivity analysis was performed to assess the robustness of findings.


RESULTS
The lowest hazard ratios (HRs) for the three PS quintiles-adjusted models were obtained by a cutoff of treatment initiation within 1 year from disease onset. Early treatment significantly reduced the risk of reaching a 1-point progression in EDSS score (HR = 0.63; 95% CI = 0.48-0.85; p < 0.002), and the EDSS 4.0 milestone (HR = 0.56; 95% CI = 0.36-0.90; p = 0.015). Sensitivity analysis showed the bound of significance for unmeasured confounders.


CONCLUSIONS
Greater benefits on disability progression may be obtained by an early IFNbeta treatment in RRMS.
Trojano
M
M
Department of Neurological and Psychiatric Sciences, University of Bari, Italy. mtrojano@neurol.uniba.it
Pellegrini
F
F
Paolicelli
D
D
Fuiani
A
A
Zimatore
G B
GB
Tortorella
C
C
Simone
I L
IL
Patti
F
F
Ghezzi
A
A
Zipoli
V
V
Rossi
P
P
Pozzilli
C
C
Salemi
G
G
Lugaresi
A
A
Bergamaschi
R
R
Millefiorini
E
E
Clerico
M
M
Lus
G
G
Vianello
M
M
Avolio
C
C
Cavalla
P
P
Lepore
V
V
Livrea
P
P
Comi
G
G
Amato
M P
MP
D000328:Adult; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D016899:Interferon-beta / Q000627:therapeutic use*; D008297:Male; D020529:Multiple Sclerosis, Relapsing-Remitting / Q000188:drug therapy* / Q000453:epidemiology / Q000523:psychology*; D011446:Prospective Studies; D011788:Quality of Life / Q000523:psychology*; D018434:Sickness Impact Profile; D013997:Time Factors; D016896:Treatment Outcome; D055815:Young Adult
D016899:Interferon-beta