Table 1.

Demographic and clinical characteristics of the study population.

	AAs	CAs	CTRLs	p-value*	p-value§
M/F (n)	5/15	6/14	8/12	0.723a	0.048 a
Age at onset [yrs]	28.6 ± 7.3	28.4 ± 6.4	-	0.841b	-
Age at MRI [yrs]	34.6 ± 10.4	33.8 ± 6.3	33.4±10.4	0.820b	0.841 c
Disease duration [yrs]	6.0 ± 4.3	5.3 ± 4.4	-	0.620b	-
EDSS score (median and range)	1.5 (1.0-6.0)	1.7 (1.0-3.5)	-	0.640b	-
9-HPT score [sec]	25.0 ± 7.2	21.6 ± 4.5	-	0.157b	-
Patient under treatment (n)	18/20	18/20	-	1a	-
Treatment exposure [yrs]	3.0 ± 3.3	4.6 ± 4.5	-	0.277b	-

Abbreviations: AAs=African Americans; CAs=Caucasians; CTRLs=controls; EDSS= Expanded Disability Status Score; F=female; M=male; n=number; yrs=years; 9-HPT=9-hole peg test. Unless otherwise specified, all values are expressed as mean ± standard deviation.

^aChi-square test.

^bMann-Whitney test.

^cKruskal-Wallis test.

^*AAs vs CAs.

^§AA vs CAs vs CTRLs.