Table 3.

Sensitivity, specificity and accuracy of the nine dysregulated proteins (FC ≥ 2, p < 0.05) that exhibited moderately strong correlation (correlation coefficient ≥ 0.60, p < 0.05) with parameters of cognitive and/or frailty assessments. See Table S3 for false positive test on diseases using single and combination of dysregulated proteins (FC ≥ 2, p < 0.05) that exhibited moderately strong correlation (correlation coefficient ≥ 0.60, p < 0.05) with parameters of cognitive and/ or frailty assessments

Protein	Optimal abundance value cutoff	Sensitivity (%)	Specificity (%)	Accuracy (%)	AUC (95% CI)
APOA1	195,731,096.6	94.74	90.00	92.31	0.92 (0.84, 1.00)
APOA2	11,892,998.6	87.50	86.84	87.18	0.89 (0.81, 0.97)
APOA4	24,091,052.3	80.95	83.33	82.05	0.89 (0.82, 0.96)
APOC1	3,561,394.5	96.55	75.51	83.33	0.91 (0.86, 0.97)
APOE	6,236,817.4	97.22	88.10	92.31	0.95 (0.91, 1.00)
GPX3	678,282.5	89.74	92.31	91.03	0.94 (0.88, 1.00)
RBP4	11,117,975.4	78.05	83.78	80.77	0.88 (0.80, 0.95)
SERPINC1	31,070,160.2	90.91	82.22	85.90	0.93 (0.88, 0.98)
TTR	23,364,280.4	87.18	89.74	88.46	0.91 (0.84, 0.98)
3-protein combination#		94.74	95.00	94.87	0.97 (0.94, 1.00)
6-protein combination^		100	93.02	96.15	0.98 (0.94, 1.00)
9-protein combination$		100	93.02	96.15	0.99 (0.97, 1.00)

AUC, area under ROC curve; CI, confidence interval; FC, fold change

^#3-protein combination include APOA1, APOE and GPX3; these three proteins exhibited accuracy ≥ 90% in individual biomarker analysis

^{^}6-protein combination include APOA1, APOA4, APOC1, APOE, GPX3 and TTR; these six proteins were correlated (correlation coefficient ≥ 0.6) with both cognitive and physical assessments

^$9-protein combination include APOA1, APOA2, APOA4, APOC1, APOE, GPX3, RBP4, SERPINC1 and TTR; these nine proteins were correlated (correlation coefficient ≥ 0.6) with parameters of cognitive and/or frailty assessments