Rate of brain atrophy in relapsing MS decreases during treatment with IFNbeta-1a.
OBJECTIVE
To determine the time course of brain atrophy during treatment with once-weekly IM interferon beta-1a (IFNbeta-1a).


METHODS
The MRI cohort (n = 386) of the European IFNbeta-1a dose comparison study in relapsing multiple sclerosis (MS) was analyzed. In addition to baseline and three annual scans, a frequent subgroup (n = 138) had two scans before treatment initiation and scans at months 4, 5, 6, 10, and 11. Brain parenchymal fraction (BPF), a normalized measure of whole-brain atrophy, and volume of Gd-enhancing lesions (T1Gd) and T2 hyperintense lesions (T2LL) were evaluated.


RESULTS
BPF decrease was -0.686% (first year), -0.377% (second year), and -0.378% (third year). Analysis of the frequent subgroup showed that 68% of the first-year BPF decrease occurred during the first 4 months of treatment. This change was paralleled by a drop in T1Gd and T2LL. In the frequent subgroup, an annualized atrophy rate was determined by a regression slope for the pretreatment period and from month 4 of treatment onward. Annualized pretreatment rate (-1.06%) was significantly higher than the under-treatment rate (-0.33%).


CONCLUSIONS
In the first year of treatment with anti-inflammatory agents, atrophy measurements are possibly confounded by resolution of inflammatory edema or more remote effects of previous damage to the CNS. The atrophy rate reduction observed after treatment month 4 may reflect a beneficial but partial effect of interferon beta-1a and was sustained over the 3-year study period.
Hardmeier
M
M
MS MRI Evaluation Centre Basel, University Hospitals Basel, Switzerland.
Wagenpfeil
S
S
Freitag
P
P
Fisher
E
E
Rudick
R A
RA
Kooijmans
M
M
Clanet
M
M
Radue
E W
EW
Kappos
L
L
D000328:Adult; D001284:Atrophy; D001921:Brain / Q000473:pathology*; D015331:Cohort Studies; D018450:Disease Progression; D005060:Europe; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007155:Immunologic Factors / Q000627:therapeutic use*; D000068556:Interferon beta-1a; D016899:Interferon-beta / Q000627:therapeutic use*; D008279:Magnetic Resonance Imaging; D008297:Male; D020529:Multiple Sclerosis, Relapsing-Remitting / Q000188:drug therapy / Q000473:pathology*; D013997:Time Factors; D016896:Treatment Outcome
D007155:Immunologic Factors; D016899:Interferon-beta; D000068556:Interferon beta-1a