TABLE 3.

Characteristics of African-Americans and Caucasians in the NACC cohort of 1622 subjects with clinically diagnosed and pathologically confirmed AD.

Variable	African-Americans (n=68)	Caucasians (n=1554)	p value
Age at death (yrs)+	81.9 ± 9.5	79.9 ± 10.5	0.13‡
Duration (yrs)+^	10.5 ± 4.0	10.3 ± 4.0	0.62‡
PMI (hrs)+^^	16.4 ± 18.2	11.7 ± 10.2	0.21‡
Gender n (%)			0.02
Male	27 (40%)	838 (54%)
Female	41 (60%)	716 (46%)
APOE genotype n (%)^^^
ε4/4	11 (20%)	205 (15%)
ε3/4	24 (44%)	597 (43%)
ε3/3	14 (26%)	488 (35%)
ε2/4	1 (2%)	46 (3%)
ε2/3	4 (7%)	43 (3%)
ε2/2	0 (0%)	2 (0.1%)
APOEε4-positive n (%)^^^			0.44‡
Yes	36 (67%)	848 (61%)
No	18 (33%)	533 (39%)
Hypertension n (%)䫨	51/62 (82%)	753/1418 (53%)	<0.001
Education (yrs)+ 䫨䫨	13.4 ± 3.4	15.3 ± 2.9	<0.001

All percentages except ε2/2 incidence in Caucasians are rounded to the nearest whole number

APOE: apolipoprotein E

PMI: postmortem interval

⁺Mean ± standard deviation

^{^}Time from diagnosis to death; Data not available for 1 African-American and 13 Caucasians

^{^^}Data not available for 43 African-Americans and 950 Caucasians

^{^^^}Data not available for 14 African-Americans and 173 Caucasians

^䫨Data not available for 6 African-Americans and 136 Caucasians

^䫨䫨Data not available for 1 African-American and 13 Caucasians

^‡Statistically non-significant