Table 2.

Comparisons of regional (substructure) brain volume fractions (normalized to intracranial volume) at baseline

Brain substructure volumes at baseline (cerebral volume fractions)
	African Americans	Caucasian Americans	African Americans versus Caucasian Americans
	(n = 32)	(n = 64)	P-valuea	P-valueb
	Mean (SD)	Mean (SD)
Whole brain	0.8304 (0.0307)	0.8301 (0.0296)	0.867	0.905
Cortical grey matter	0.3857 (0.0212)	0.3883 (0.0188)	0.303	0.319
Cerebral white matter	0.2867 (0.0200)	0.2867 (0.0187)	0.952	0.996
Whole thalamus	0.0079 (0.0012)	0.0082 (0.0011)	0.064	0.059
Nucleus thalamus	0.0102 (0.0018)	0.01073 (0.0014)	0.058	0.056
Deep grey matter	0.0307 (0.0038)	0.0310 (0.0032)	0.558	0.572
T2 lesions	0.0056 (0.0063)	0.0032 (0.0035)	0.007	0.007

^aDerived from models adjusted for age and sex.

^bDerived from models adjusted by sex, age at baseline, disease duration and history optic neuritis. Bold values indicate statistical significance (P < 0.05).