Table 1.

Demographic and clinical data for the amyloid-negative healthy controls (Aβneg HC) and the patients with amnestic mild cognitive impairment (aMCI) categorized by amyloid status (Aβpos aMCI and Aβneg aMCI)

Measure	Aβneg HC (n = 24)	Aβneg aMCI (n = 20)	Aβpos aMCI (n = 24)	Group comparison
Age: years ± SD	71.4 ± 4.4	73.1 ± 7.6	73.3 ± 6.7	PANOVA = .52
Gender: % male	46	50	58	$P_{{\mathrm{\chi }}^{\mathrm{2}}}=.68$
Education: years ± SD	11.8 ± 3.9	9.9 ± 2.8	11.9 ± 4.3	PANOVA = .16
MMSE: score ± SD	28.7 ± 1.0	26.9 ± 1.8	26.8 ± 1.7	PANOVA < .001; Aβneg HC > Aβneg aMCI, Aβpos aMCI
MADRS: score ± SD	142.5 ± 1.3	134.3 ± 4.7	133.5 ± 6.1	PANOVA < .001; Aβneg HC > Aβneg aMCI, Aβpos aMCI
APOE: % ε4 carriers	4.2	20.0	77.3	$P_{{\mathrm{\chi }}^{\mathrm{2}}}$ < .001; Aβpos aMCI > Aβneg aMCI, Aβneg HC

Abbreviations: MMSE, Mini–Mental State Examination; MADRS, Mattis Dementia Rating Scale; SD, standard deviation; ANOVA, analysis of variance.

NOTE. All variables were compared using ANOVA and χ² (Pearson) tests.