. 2021 Mar 4;89(5):987–1000. doi: 10.1002/ana.26048

TABLE 1.

Cohort Characteristics

	Total Cohort	PET Visual Read Normal	PET Visual Read Abnormal
n ^a	197	167	27
Singletons ^b	7	5	1
Age, yr, mean (SD)	70.3 (7.4)	70.0 (7.2)	75.0 (7.2) ^c
Female gender, n (%)	112 (57)	96 (57)	16 (59)
Education, yr, mean (SD)	11.5 (2.6)	11.5 (2.6)	11.4 (3.0)
MMSE, mean (SD)	29.0 (1.1)	29.1 (1.1)	28.6 (1.5)
APOE ε4 carrier, n (%) ^d	65 (33)	50 (30)	14 (52) ^e
CSF markers, n (%)	126 (64)	105 (63)	18 (67)
BACE1, pg/ml, mean (SD)	2,370 (747)	2,306 (696)	2,744 (960)
Aβ1–40, pg/ml, mean (SD)	9,592 (2,844)	9,289 (2,700)	11,409 (3,114)
Aβ1–38, pg/ml, mean (SD)	2,424 (737)	2,370 (715)	2,805 (797)
Aβ1–42/1–40 ratio, mean (SD)	0.10 (0.03)	0.10 (0.02)	0.05 (0.02) ^c
t‐tau, pg/ml, mean (SD)	412 (143)	379 (111)	620 (146)
p‐tau, pg/ml, mean (SD)	76 (44)	64 (20)	154 (66) ^c
Dynamic PET, n (%)	188 (95)	162 (97)	26 (96) ^c
Global cortical amyloid deposition, mean (SD), BP_ND	0.16 (0.12)	0.12 (0.06)	0.43 (0.13) ^c
Concordance status visual read amyloid positivity, n (%) ^f
Concordant negative pairs	74 (79)
Concordant positive pairs	6 (6)
Discordant pairs	14 (15)

PET visual read was based on BP_ND image.

^{^a}

PET data were missing in 3 subjects.

^{^b}

In 1 twin‐pair, PET was missing for 1 subject; the other twin had a normal scan and is counted as a singleton for PET analysis.

^{^c}

p < 0.01 versus normal PET group for amyloid measures corrected for age, gender, and APOE ε4.

^{^d}

APOE status was missing in 2 subjects.

^{^e}

p < 0.05 versus normal PET group for amyloid measures corrected for age, gender, and APOE ε4.

^{^f}

Ninety‐four twin‐pairs with PET visual read available for both.

Aβ = amyloid‐beta; APOE = apolipoprotein E; BACE1 = beta‐secretase 1; BP_ND = nondisplaceable binding potential; CSF = cerebrospinal fluid; MMSE = Mini‐Mental State Examination; PET = positron emission tomography; p‐tau = 181‐phosphorylated‐tau; SD = standard deviation; t‐tau = total‐tau.