Table 5.

Multivariable hazard ratios (HR) and 95 % confidence intervals (CIs) for risk of endometrial cancer by tertiles of 16-pathway metabolites

Estrogen/EM	Cases (n = 66)	Subcohort (n = 346)	HR (95 % CI)a	HR (95 % CI)b	HR (95 % CI)c
16-Pathway metabolites
Estriol (E3)
T1	15	114	1.00	1.00	1.00
T2	21	115	1.12 (0.54, 2.32)	0.98 (0.46, 2.08)	0.92 (0.43, 1.97)
T3	30	117	1.70 (0.84, 3.45)	1.41 (0.67, 2.95)	0.86 (0.39, 1.93)
p trend			0.12	0.32	0.72
16α-Hydroxyestrone
T1	10	114	1.00	1.00	1.00
T2	19	114	1.57 (0.68, 3.65)	1.44 (0.59, 3.54)	1.30 (0.55, 3.08)
T3	37	118	2.69 (1.26, 5.71)	2.37 (1.05, 5.35)	1.50 (0.65, 3.46)
p trend			0.009	0.04	0.36
17-Epiestriol	23	115	1.00	1.00	1.00
T1	25	114	1.25 (0.62, 2.53)	1.06 (0.50, 2.26)	1.12 (0.56, 2.26)
T2	18	117	0.85 (0.41, 1.75)	0.72 (0.34, 1.52)	0.37 (0.16, 0.88)
T3			0.67	0.39	0.03
p trend
16-Epiestriol
T1	23	115	1.00	1.00	1.00
T2	16	114	0.67 (0.32, 1.38)	0.59 (0.27, 1.28)	0.58 (0.28, 1.22)
T3	27	117	1.29 (0.67, 2.49)	1.06 (0.53, 2.16)	0.66 (0.31, 1.42)
p trend			0.45	0.70	0.29
16-Ketoestradiol
T1	15	114	1.00	1.00	1.00
T2	25	115	1.62 (0.80, 3.28)	1.37 (0.66, 2.84)	1.43 (0.70, 2.93)
T3	26	117	1.66 (0.83, 3.29)	1.36 (0.65, 2.85)	0.89 (0.40, 1.86)
p trend			0.16	0.41	0.64

The following tertile categories (T1, T2, T3 pmol/L) determined based on the distribution of each estrogen or estrogen metabolites among the subcohort: estriol (<184.94, 184.94–298.18, >298.18), 16α-hydroxyestrone (<22.13, 22.13–34.03, >34.03), 17-epiestriol (<2.37, 2.37–3.83, >3.83), 16-epiestriol (<3.19, 3.19–5.37, >5.37), 16-ketoestradiol (<24.87, 24.87–36.84, >36.84)

^aAdjusted for clinic and trial participation status

^bAdjusted for clinic, trial participation status, and body mass index

^cAdjusted for clinic, trial participation status, and estradiol