Table 4.

Pearson correlations of log-transformed data on kynurenine pathway metabolites and enzymes with cytokines

Cytokine*	Kynurenine	Kynurenine/TRP	KYNA	QUIN	IDO1	IDO2	TDO2	KAT II	KMO
IL6 (n = 70)
r	0.325	0.428	0.304	0.230	0.347	0.366	0.279	0.054	0.224
p†	0.006	< 0.001	0.011	0.06	0.004	0.003	0.021	0.67	0.06
adj p‡	0.015	0.001	0.024	0.09	0.009	0.007	0.039	0.70	0.10
IL13 (n = 69)
r	0.241	0.278	0.121	0.162	0.484	0.507	0.501	0.150	0.360
p†	0.046	0.021	0.32	0.19	< 0.001	< 0.001	< 0.001	0.22	0.002
adj p‡	0.08	0.039	0.38	0.23	0.001	0.001	0.001	0.27	0.007
IL33 (n = 56)
r	−0.067	0.413	0.119	0.166	0.415	0.467	0.540	0.381	0.341
p†	0.63	0.002	0.38	0.22	0.002	< 0.001	< 0.001	0.004	0.010
adj p‡	0.68	0.005	0.44	0.27	0.005	0.002	< 0.001	0.010	0.023
IFN-γ (n = 69)
r	0.087	0.262	0.035	0.190	0.689	0.755	0.533	0.167	0.381
p†	0.48	0.030	0.78	0.12	< 0.001	< 0.001	< 0.001	0.18	0.001
adj p‡	0.53	0.05	0.79	0.17	< 0.001	< 0.001	< 0.001	0.23	0.005
TNF-α (n = 69)
r	0.162	0.302	0.169	0.236	0.495	0.437	0.450	0.024	0.360
p†	0.18	0.012	0.17	0.05	< 0.001	< 0.001	< 0.001	0.85	0.002
adj p‡	0.23	0.024	0.22	0.09	< 0.001	0.001	< 0.001	0.85	0.007
CCL2 (n = 69)
r	0.170	0.449	0.362	0.297	0.210	0.230	−1.02	0.047	0.170
p†	0.16	< 0.001	0.002	0.013	0.08	0.07	0.41	0.70	0.16
adj p‡	0.22	0.001	0.007	0.027	0.13	0.10	0.46	0.73	0.22

adj = adjusted; CCL2 = chemokine ligand 2; IDO = indoleamine 2,3-dioxygenase; IFN = interferon; IL = interleukin; KAT II = kynurenine aminotransferase II; KMO = kynurenine 3-monooxygenase; KYNA = kynurenic acid; QUIN = quinolinic acid; TDO = tryptophan-2,3-dioxygenase; TNF = tumour necrosis factor; TRP = tryptophan.

^*The n value includes both controls and depressed individuals.

^†Significance level for unadjusted values for multiple comparisons.

^‡Adjusted for multiple comparisons using the Benjamini–Hochberg modification of the Bonferroni method.