Table 2.

Linear mixed-effects models and parameter estimates for whole brain fraction, ventricle fraction, thalamus fraction, lesion fraction, and a second lesion fraction model (with exclusively year 1 GFAP values).

Whole brain fraction			Ventricular fraction
AIC = 553.2			AIC = 215.2
Fixed effects	Std. β	p Value	Fixed effects	Std. β	p Value
Baseline age	−0.08 (−0.28 to 0.11)	0.402	Baseline age	0.1 (−0.13 to 0.34)	0.373
Female sex	0.17 (−0.23 to 0.57)	0.411	Female sex	−0.13 (−0.6 to 0.35)	0.601
Disease duration	−0.27 (−0.47 to −0.07)	0.008	Disease duration	0.23 (−0.01 to 0.46)	0.059
Ln GFAP	−0.05 (−0.17 to 0.08)	0.447	Ln GFAP	−0.04 (−0.09 to 0.01)	0.162
Time	−0.21 (−0.28 to −0.14)	<0.001	Time	0.03 (0.01–0.06)	0.002
Ln GFAP × time	−0.03 (−0.09 to 0.04)	0.441	Ln GFAP × time	0.01 (0–0.04)	0.148
Thalamic fraction			Lesion fraction
AIC = 330.1			AIC = 323.4
Fixed effects	Std. β	p Value	Fixed effects	Std. β	p Value
Baseline age	0.14 (−0.09 to 0.36)	0.227	Baseline age	0.01 (−0.2 to 0.23)	0.887
Female sex	0.25 (−0.2 to 0.7)	0.275	Female sex	0.26 (−0.18 to 0.7)	0.243
Disease duration	−0.35 (−0.57 to −0.12)	0.003	Disease duration	0.26 (0.05–0.48)	0.018
Ln GFAP	−0.02 (−0.09 to 0.06)	0.659	Ln GFAP	0.09 (0.01–0.16)	0.019
Time	−0.09 (−0.13 to −0.06)	<0.001	Time	−0.06 (−0.09 to −0.03)	<0.001
Ln GFAP × time	0.01 (−0.02 to 0.04)	0.657	Ln GFAP × time	−0.07 (−0.1 to −0.04)	<0.001

For GFAP levels and MRI volumes, time points included were 12M, 24M, and last clinical follow-up. GFAP levels were natural log transformed.

AIC: Akaike information criteria; sGFAP: serum glial fibrillary acidic protein; 12M: 12 months after baseline; 24M: 24 months after baseline.