Combination of plasma amyloid beta(1-42/1-40) and glial fibrillary acidic protein strongly associates with cerebral amyloid pathology

Table 1 Demographics, clinical characteristics, and plasma marker concentrations of the total study population and stratified for amyloid PET status

		Stratified for amyloid PET status
	Total	Amyloid negative	Amyloid positive
	*n = 252*	*76 (30%)*	*176 (70%)*
Age	63 ± 8	61 ± 9	63 ± 7
Female sex	114 (45%)	27 (36%)	87 (49%) *
Education	5.3 ± 1.2	5.5 ± 1.3	5.2 ± 1.2
Syndrome diagnosis (SCD/MCI/AD-dementia)	70/50/132	52/24/0	18/26/132 **
APOE ε4 carriership	134 (53%)	18 (24%)	116 (66%) **
MMSE	24 ± 4	27 ± 2	23 ± 4 **
MTA score	1 (0–1.5)	0.5 (0–1)	1 (0.5–1.5) **
Plasma Abeta_(1-42/1-40)	0.15 ± 0.03	0.17 ± 0.03	0.14 ± 0.03 *
Plasma Abeta_(1-42), pg/mL	24 ± 6	27 ± 6	23 ± 6 *
Plasma Abeta_(1-40), pg/mL	160 ± 29	165 ± 30	157 ± 28 *
Plasma GFAP, pg/mL	146 ± 78	96 ± 53	168 ± 77 **
Plasma NfL, pg/mL	14 ± 9	11 ± 6	15 ± 10

Baseline features of the total study population and stratified for visually read amyloid PET status is presented as mean ± SD, median (25th–75th percentile) or n (%). Education scoring is according to the Verhage (1965) system with a scale ranging from 1 to 7. Demographic and clinical differences between the two groups were calculated using independent t tests, chi-square tests, or Mann-Whitney U test as appropriate. Differences between plasma biomarker levels were calculated using two-way ANOVA for PET status and syndrome diagnosis adjusted for age and sex, of which the p value of the independent effect of PET status is presented here. Raw plasma biomarker values are presented in the table, but prior to statistical analysis Abeta_(1-40), NfL and GFAP were natural log-transformed for normality of the data. APOE status was available for n = 244, MTA score (average of right and left) was available for n = 182, plasma Abeta_(1-42/1-40) and Abeta_(1-42) for n = 238, plasma Abeta_(1-40) for n = 240, plasma GFAP for n = 247, and plasma NfL for n = 251
PET positron emission tomography, SCD subjective cognitive decline, MCI mild cognitive impairment, AD Alzheimer’s disease, APOE apolipoprotein E, MMSE mini mental state examination, MTA medial temporal lobe atrophy, Abeta amyloid beta, GFAP Glial fibrillary acidic protein, NfL Neurofilament light
*p < 0.05
**p < 0.001

ISSN: 1758-9193