Comparison of ultrasensitive and mass spectrometry quantification of blood-based amyloid biomarkers for Alzheimer’s disease diagnosis in a memory clinic cohort

Table 2 Baseline and follow-up amyloid biomarker concentrations according to diagnosis and analytical technique

Biomarker	AD (n = 10)		p value^a	Non-AD (n = 19)		p value^a
Biomarker	Baseline	Follow-up	p value^a	Baseline	Follow-up	p value^a
Simoa Aβ₄₀	233 (194–283)	198 (180–274)	0.94	230 (180–254)	197 (149–224)	0.18
IPMS-Shim Aβ₄₀	36 (28–38)	23 (18–33)	0.027	29 (24–33)	27 (22–30)	0.045
Simoa Aβ₄₂	11 (9–13)	10 (8–13)	0.94	13 (11–15)	12 (9–13)	0.71
IPMS-Shim Aβ₄₂	0.55 (0.42–0.61)	0.37 (0.29–0.51)	0.020	0.53 (0.46–0.65)	0.54 (0.45–0.58)	0.23
Simoa Aβ_42/40	0.055 (0.041–0.057)	0.054 (0.042–0.057)	0.69	0.057 (0.052–0.062)	0.058 (0.054–0.077)	0.044
IPMS-Shim Aβ_42/40	0.016 (0.015–0.018)	0.016 (0.015–0.017)	0.56	0.018 (0.017–0.021)	0.02 (0.018–0.023)	0.17
IPMS-Shim composite	5.1 (4.7–5.3)	5.4 (4.5–6.2)	0.77	4 (2.7–4.7)	3.1 (2.1–3.9)	0.14

Biomarker concentrations are expressed as the median with (IQR, Q1–Q3) in pg/ml
Abbreviations: AD, Alzheimer’s disease; non-AD: 8 MCI, 5 SCI, 3 NDD, and 3 OND; Aβ₄₀, 40-amino acid-long Aβ peptide; Aβ₄₂ 42-amino acid-long Aβ peptide
^aWilcoxon signed-rank test (for paired data)

ISSN: 1758-9193