Table 2.

Statistically significant metabolites between AD and iNPH in the metabolomics

		Mean concentration, μmol/L (SD)				Welch’s t-test	ROC	AD/iNPH	Valid value		Missing value
PubChem ID	Metabolite	AD		iNPH		P-value	AUC	Fold change	AD	iNPH	AD	iNPH
752	Glycerate	60.61	(30.94)	26.23	(6.22)	6.E-07	0.88	2.31	32	16	7	3
1060	Pyruvate	45.22	(13.45)	68.34	(12.95)	1.E-04	0.89	0.66	12	16	27	3
3441	2-Oxoisopentanoate	4.29	(1.19)	5.64	(1.29)	0.001	0.78	0.76	30	19	9	0
3568	N-Acetylneuraminate	16.75	(3.89)	13.35	(3.2)	0.001	0.76	1.25	39	19	0	0
617	Serine	24.63	(3.9)	30.12	(6.15)	0.002	0.77	0.82	39	19	0	0
273,260	N-Acetylhistidine^a	1.19	(0.88)	0.88	(0.92)	0.002	0.72	1.36	39	19	0	0
8180	Undecanoate^a	0.54	(0.17)	0.71	(0.09)	0.003	0.81	0.76	17	7	22	12
3,527,278	4-Methyl-2-oxopentanoate	2.64	(0.85)	3.51	(0.98)	0.003	0.74	0.75	39	19	0	0
11,266	2-Hydroxybutyrate	18.08	(5.98)	23.14	(6.06)	0.005	0.74	0.78	39	19	0	0
525	Malate	1.17	(0.33)	1.54	(0.46)	0.005	0.73	0.76	39	19	0	0
602	Alanine	32.03	(8.53)	42.82	(14.42)	0.006	0.77	0.75	39	19	0	0
876	Methionine	2.79	(1.08)	3.67	(1.07)	0.006	0.76	0.76	39	19	0	0
205	Threonine	27.56	(6.43)	34.81	(9.53)	0.006	0.73	0.79	39	19	0	0
232	Arginine	23.08	(4.5)	26.79	(4.6)	0.006	0.71	0.86	39	19	0	0
64,969	3-Methylhistidine	1.12	(0.88)	1.81	(0.92)	0.010	0.79	0.62	39	19	0	0
1081	Citramalate	1.20	(0.96)	0.57	(0.12)	0.010	0.74	2.12	19	8	20	11
1175	Urate	20.84	(11.36)	30.61	(15.74)	0.023	0.73	0.68	39	19	0	0
866	Lysine	30.00	(5.84)	36.35	(10.66)	0.023	0.72	0.82	39	19	0	0

^aUndecanoate and N-Acetylhistidine were excluded from further analysis

AD Alzheimer’s disease, iNPH idiopathic normal pressure hydrocephalus, AUC area under the curve, ROC receiver operator characteristic