Table 1:

Baseline group characteristics

Characteristic	Microbleeds Absent	P Value^{^a}	Microbleeds Present			P Value^{^b}
Characteristic	Microbleeds Absent	P Value^{^a}	Lobar Microbleeds Only	Mixed Lobar and Deep Gray/ Infratentorial Microbleeds	Deep Gray/Infratentorial Microbleeds Only	P Value^{^b}
No. of subjects	407		163	29	27
Mean age (SD), y	72 (7.6)	<.001^{^c}	74 (7.0)	77 (6.4)	77 (9.0)	.06
Sex, male/female	218:189	.15	100:63	17:12	14:13	.64
Mean education (SD), y	16 (2.6)	.24	16 (2.9)	16 (2.9)	16 (2.3)	.78
% with HTN	47	.28	46	72	67	.009^{^d}
% with APOE4	43	.15	53	52	26	.03^{^d}
% with APOE2 allele	7	>.99	6	7	19	.06
% with NL	26	.14	20	10	33	.10
% with MCI	61	.80	61	79	56	.33
% with AD	12	.18	18	10	11	.41

Note:—HTN indicates hypertension; MCI, mild cognitive impairment; NL, normal cognitive function; SD, standard deviation.
↵a P values compare baseline variables between those without microbleeds and those with microbleeds (combining the 3 groups with different types of microbleeds).
↵b P values compare baseline variables among the 3 groups with microbleeds.
↵c Significance according to the Wilcoxon rank sum test.
↵d Significance according to the χ² test.