Predicting gadolinium enhancement status in MS patients eligible for randomized clinical trials.
BACKGROUND
Gadolinium enhancement is often used in randomized clinical trials to evaluate the efficacy of new drugs in multiple sclerosis (MS). Knowledge about predictors of enhancement status is important for the selection of patients for MRI monitored trials.


METHODS
Data from 17 trials were available in anonymized format through the Sylvia Lawry Centre for MS Research. In an open part containing 1,328 (non primary progressive) patients, two logistic regression analyses were explored, including demographic, clinical, and MRI predictors. The authors examined the area under the curve (AUC) and the increase in positive predictive value (PPV). The final selection of models was validated in a closed part of 848 comparable patients.


RESULTS
Age at onset, disease duration, and disease course (CIS/RR/SP) were important predictors from the multivariate models. Further, a multivariate model including T2 burden of disease was more predictive than one with only clinical predictors (AUC 0.719 vs 0.625, p < 0.001). For the model with T2 burden of disease, the PPV was 66.8%, compared to 58.5% for the model without (a priori chance 46.4%). These findings were unequivocally confirmed in the closed part of the database.


CONCLUSIONS
Gadolinium status can be predicted by a set of baseline variables, certainly when T2 burden of disease is included. These findings may benefit the design and statistical power of future randomized clinical trials.
Barkhof
F
F
Department of Radiology, VU Medical Centre, P.O. Box 7057, 1007 MB Amsterdam, The Netherlands. f.barkhof@vumc.nl.
Held
U
U
Simon
J H
JH
Daumer
M
M
Fazekas
F
F
Filippi
M
M
Frank
J A
JA
Kappos
L
L
Li
D
D
Menzler
S
S
Miller
D H
DH
Petkau
J
J
Wolinsky
J
J
D000328:Adult; D017668:Age of Onset; D001921:Brain / Q000187:drug effects / Q000473:pathology / Q000503:physiopathology; D015984:Causality; D003937:Diagnosis, Differential; D004185:Disability Evaluation; D005260:Female; D005682:Gadolinium; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000592:standards*; D008297:Male; D009103:Multiple Sclerosis / Q000175:diagnosis* / Q000188:drug therapy / Q000503:physiopathology; D015999:Multivariate Analysis; D009413:Nerve Fibers, Myelinated / Q000473:pathology; D016017:Odds Ratio; D018579:Patient Selection; D011237:Predictive Value of Tests; D016032:Randomized Controlled Trials as Topic / Q000592:standards*; D012008:Recurrence; D015203:Reproducibility of Results; D016896:Treatment Outcome
D005682:Gadolinium