Table 2. Multivariate associations between all maternal plasma metabolites and eczema development by 6, 12 and 18 months in the offspring.

	6 months (n=782)		12 months (n=732)		18 months (n=667)
	RR (95% CI)	p-value *	RR (95% CI)	p-value *	RR (95% CI)	p-value *
N1-methylnicotinamide		0.102		0.167		0.423
Lowest	1.0		1.0		1.0
2nd	0.88(0.44 – 1.76)	0.714	1.1(0.6 – 2.1)	0.704	1.1(0.7 – 1.8)	0.708
3rd	0.71(0.34 – 1.50)	0.370	0.92(0.49 – 1.73)	0.788	0.82(0.48 – 1.39)	0.451
Highest	0.58(0.25 – 1.34)	0.202	0.65(0.32 – 1.34)	0.245	0.88(0.50 – 1.57)	0.672
Nicotinamide		0.004		0.019		0.136
Lowest	1.0		1.0		1.0
2nd	1.8(0.8 – 4.2)	0.192	1.7(0.9 – 3.4)	0.123	1.1(0.7 – 1.9)	0.683
3rd	2.3(1.0 – 5.4)	0.055	1.6(0.8 – 3.3)	0.177	1.1(0.6 – 1.9)	0.735
Highest	3.2(1.4 – 7.6)	0.008	2.2(1.1 – 4.6)	0.029	1.4(0.8 – 2.4)	0.244
Trigonelline		0.858		0.352		0.649
Lowest	1.0		1.0		1.0
2nd	0.81(0.41 – 1.59)	0.532	0.92(0.53 – 1.61)	0.781	0.95(0.59 – 1.50)	0.812
3rd	0.80(0.40 – 1.58)	0.522	0.83(0.47 – 1.48)	0.525	1.0(0.6 – 1.6)	0.948
Highest	0.94(0.44 – 2.02)	0.880	0.82(0.43 – 1.58)	0.548	0.86(0.50 – 1.45)	0.565
3-Hydroxyanthranilic acid		0.512		0.264		0.032
Lowest	1.0		1.0		1.0
2nd	1.2(0.5 – 2.5)	0.702	0.93(0.48 – 1.81)	0.822	1.2(0.7 – 2.0)	0.504
3rd	1.3(0.6 – 2.8)	0.489	1.6(0.8 – 3.0)	0.160	1.6(0.9 – 2.8)	0.086
Highest	1.4(0.6 – 3.4)	0.432	1.4(0.7 – 3.0)	0.358	1.9(1.1 – 3.6)	0.031
3-Hydroxykynurenine		0.023		0.135		0.387
Lowest	1.0		1.0		1.0
2nd	1.8(0.8 – 4.0)	0.167	1.7(0.9 – 3.3)	0.094	1.6(1.0 – 2.7)	0.068
3rd	2.7(1.2 – 6.1)	0.017	1.9(0.9 – 3.8)	0.076	1.5(0.9 – 2.7)	0.118
Highest	2.9(1.2 – 7.0)	0.020	1.8(0.9 – 3.9)	0.123	1.5(0.8 – 2.7)	0.192
Anthranilic acid		0.305		0.098		0.152
Lowest	1.0		1.0		1.0
2nd	0.71(0.36 – 1.41)	0.334	0.72(0.40 – 1.31)	0.285	0.72(0.45 – 1.16)	0.178
3rd	0.70(0.34 – 1.44)	0.333	0.71(0.38 – 1.31)	0.272	0.72(0.44 – 1.17)	0.179
Highest	0.72(0.33 – 1.56)	0.402	0.56(0.28 – 1.12)	0.103	0.68(0.39 – 1.16)	0.155
Kynurenic acid		0.682		0.699		0.361
Lowest	1.0		1.0		1.0
2nd	1.2(0.5 – 2.6)	0.734	1.2(0.6 – 2.4)	0.628	0.94(0.55 – 1.64)	0.838
3rd	1.0(0.4 – 2.7)	0.956	1.2(0.6 – 2.8)	0.590	0.84(0.45 – 1.59)	0.595
Highest	0.81(0.27 – 2.42)	0.702	1.2(0.5 – 3.0)	0.702	0.79(0.38 – 1.64)	0.524
Kynurenine		0.080		0.067		0.338
Lowest	1.0		1.0		1.0
2nd	0.87(0.42 – 1.80)	0.713	1.0(0.6 – 1.9)	0.891	0.96(0.58 – 1.58)	0.878
3rd	0.72(0.32 – 1.62)	0.423	0.87(0.44 – 1.70)	0.675	0.84(0.48 – 1.46)	0.530
Highest	0.36(0.13 – 1.01)	0.053	0.44(0.19 – 1.04)	0.061	0.71(0.36 – 1.40)	0.321
Quinolinic acid		0.362		0.643		0.597
Lowest	1.0		1.0		1.0
2nd	0.59(0.27 – 1.29)	0.187	0.73(0.39 – 1.38)	0.329	0.63(0.38 – 1.07)	0.086
3rd	0.77(0.34 – 1.72)	0.518	0.76(0.39 – 1.49)	0.418	0.77(0.45 – 1.33)	0.352
Highest	1.3(0.6 – 3.2)	0.520	1.1(0.5 – 2.4)	0.741	0.70(0.37 – 1.33)	0.280
Tryptophan		0.475		0.179		0.153
Lowest	1.0		1.0		1.0
2nd	1.2(0.5 – 2.6)	0.711	1.3(0.7 – 2.5)	0.468	1.6(0.9 – 2.8)	0.085
3rd	1.2(0.5 – 2.7)	0.642	1.5(0.8 – 3.0)	0.235	1.6(0.9 – 2.8)	0.107
Highest	1.3(0.6 – 3.0)	0.547	1.5(0.7 – 3.0)	0.325	1.6(0.9 – 3.0)	0.115
Xanthurenic acid		0.680		0.602		0.894
Lowest	1.0		1.0		1.0
2nd	0.47(0.21 – 1.08)	0.075	0.62(0.31 – 1.26)	0.187	0.93(0.54 – 1.61)	0.803
3rd	0.60(0.25 – 1.44)	0.257	0.76(0.36 – 1.61)	0.474	0.91(0.49 – 1.71)	0.771
Highest	0.72(0.27 – 1.94)	0.514	0.70(0.29 – 1.66)	0.413	1.0(0.5 – 2.0)	0.997

RR = 1.0 is the reference category.

p values of trend of metabolites in italics

Benjamini-Hochberg correction with false discovery rate at 0.20 and n=132 was applied. No associations were significant after correction.

^*Adjusted for ethnicity, maternal education level, maternal history of allergy, parity, infant sex and type of milk feed