Combination of gut microbiota and plasma amyloid-β as a potential index for identifying preclinical Alzheimer’s disease: a cross-sectional analysis from the SILCODE study

Table 3 The AUC and sensitivity and specificity at Youden’s cutoff to identify CN+ participants

	AUC (95% CI)	Youden’s cut point	Sensitivity (%)	Specificity (%)	P value
Plasma Aβ markers
Plasma Aβ₄₀	0.539 (0.399 ~ 0.679)	663.7 pg/mL	81.25	32.35	0.586
Plasma Aβ₄₂	0.660 (0.528 ~ 0.792)	11.69 pg/mL	81.25	52.94	0.025
Plasma Aβ₄₂/Aβ₄₀	0.715 (0.591 ~ 0.838)	0.015	71.88	67.65	0.003
*Panel 1*	0.730 (0.608 ~ 0.852)	0.510	68.75	73.53	0.001
Gut microbiota
Taxa1	0.686 (0.555 ~ 0.817)	0.500	68.75	67.65	0.009
Taxa2	0.775 (0.663 ~ 0.887)	0.625	56.25	88.24	< 0.001
Taxa3	0.734 (0.613 ~ 0.855)	0.574	68.75	73.53	0.001
*Panel 2*	0.810 (0.707 ~ 0.912)	0.383	87.50	64.71	< 0.001
Cognitive scores
*Panel 3*	0.802 (0.691 ~ 0.912)	0.573	68.75	88.24	< 0.001
Combined model
*Panel 4*	0.869 (0.782 ~ 0.955)	0.356	87.50	73.53	< 0.001

Taxa 1, combined phylum Bacteroidetes, class Bacteroidia, and order Bacteroidales
Taxa 2, combined phylum Firmicutes, class Clostridia, order Clostridiales, family Lachnospiraceae, family Ruminococcaceae, and genus Faecalibacterium
Taxa 3, combined class Deltaproteobacteria, order Desulfovibrionales, family Desulfovibrionaceae, and genus Bilophila
Panel 1, the combined plasma Aβ₄₀, Aβ₄₂, and Aβ₄₂/Aβ₄₀
Panel 2, the combined taxa 1, taxa 2, and taxa 3
Panel 3, the combined clinical cognitive tests (MoCA-B, AVLT-long delayed recall, AVLT-R, STT-A, STT-B, AFT, BNT)
Panel 4, the combined plasma Aβ markers, gut taxa, and cognitive tests
Abbreviations: AUC area under curve, Aβ amyloid-β, CN+ amyloid-β-positive cognitively normal participants

ISSN: 1758-9193