Table 1.

Characteristics of study participants.

Characteristics	Healthy controls	Preclinical AD	Early symptomatic AD	P-value
n	140	34	26
Clinical dementia rating (CDR)	0	0	0.5
Age, years	61.1 ± 8.1	62.6 ± 7.0	75.0 ± 5.7	<0.001
Male sex	53 (37.9%)	11(32.4%)	16 (61.5%)	0.0468
APOE e4 +	18 (12.9%)	26 (76.5%)	23 (88.5%)	<0.001
MMSE	29.4 ± 0.9	29.3 ± 1.3	25.5 ± 2.7	<0.001
CDR-sumbox	0.0 ± 0.1	0.0 ± 0.0	2.7 ± 1.0	<0.001
CSF Aβ42 (pg/ml)	786.1 ± 200.7	375.3 ± 76.1	325.1 ± 71.9	<0.001
CSF t-tau (pg/ml)	206.9 ± 61.2	228.8 ± 101.8	507.4 ± 240.6	<0.001

Data are presented as mean (SD) or number (%).

Healthy controls: participants with ≥459 pg/ml Aβ42 and ≤ 339 pg/ml total tau in the cerebrospinal fluid (CSF) and with normal cognition (CDR = 0).

Preclinical AD: participants with <459 pg/ml Aβ42 in the CSF and with normal cognition (CDR = 0).

Early symptomatic AD: participants with <459 pg/ml Aβ42 in the CSF and with very mild AD dementia (CDR = 0.5).

APOE ε4 +, positive for at least one apolipoprotein E ε4-allele.

MMSE: Mini-Mental State Exam.