Table 6.

Associations between urinary phthalate metabolite concentrations ($\mathrm{\mu }\mathrm{g}/\mathrm{g}$ creatinine) and breast cancer–specific mortality in the LIBCSP, stratified by body mass index (BMI) and estrogen receptor (ER) status.

Analytea	BMI ($n=665$) [HR (95% CI)]b			ER status ($n=454$) [HR (95% CI)]d
	$<25.0{\mathrm{kg}/\mathrm{m}}^2$ ($n\text{deaths}=30$, $n\text{censored}=267$)	$\ge 25.0{\mathrm{kg}/\mathrm{m}}^2$ ($n\text{deaths}=60$, $n\text{censored}=308$)	${\mathrm{P}}_{\text{Interaction}}$c	$\text{ER}+$ ($n\text{deaths}=46$, $n\text{censored}=300$)	$\text{ER}-$ ($n\text{deaths}=30$, $n\text{censored}=78$)	${\mathrm{P}}_{\text{Interaction}}$c
MEP
Tertile 1	1.00	1.00	—	1.00	1.00	—
Tertile 2	0.66 (0.26, 1.64)	1.40 (0.77, 2.55)	—	1.08 (0.55, 2.11)	1.51 (0.58, 3.97)	—
Tertile 3	0.72 (0.31, 1.67)	0.91 (0.47, 1.75)	—	0.75 (0.36, 1.59)	0.60 (0.23, 1.58)	—
Ln(MEP)	0.93 (0.71, 1.22)	0.98 (0.80, 1.21)	0.63	0.92 (0.72, 1.16)	0.94 (0.71, 1.25)	0.77
MnBP
Tertile 1	1.00	1.00	—	1.00	1.00	—
Tertile 2	0.54 (0.22, 1.34)	0.98 (0.55, 1.74)	—	0.57 (0.29, 1.15)	1.35 (0.56, 3.26)	—
Tertile 3	0.48 (0.20, 1.18)	0.58 (0.29, 1.16)	—	0.43 (0.21, 0.91)	0.85 (0.31, 2.32)	—
Ln(MnBP)	0.81 (0.53, 1.23)	0.87 (0.63, 1.19)	0.61	0.84 (0.59, 1.19)	0.99 (0.63, 1.57)	0.60
MiBP
Tertile 1	1.00	1.00	—	1.00	1.00	—
Tertile 2	0.99 (0.43, 2.29)	1.01 (0.55, 1.83)	—	0.99 (0.49, 2.00)	0.89 (0.38, 2.06)	—
Tertile 3	0.63 (0.24, 1.66)	0.75 (0.39, 1.43)	—	0.84 (0.41, 1.74)	0.56 (0.20, 1.59)	—
Ln(MiBP)	0.99 (0.69, 1.40)	0.86 (0.66, 1.11)	0.18	0.99 (0.75, 1.30)	0.92 (0.62, 1.37)	0.77
MCPP
Tertile 1	1.00	1.00	—	1.00	1.00	—
Tertile 2	0.89 (0.35, 2.26)	0.45 (0.25, 0.84)	—	0.46 (0.22, 0.95)	0.89 (0.34, 2.34)	—
Tertile 3	1.70 (0.72, 4.01)	0.48 (0.25, 0.94)	—	0.69 (0.34, 1.40)	0.88 (0.36, 2.19)	—
Ln(MCPP)	1.34 (0.79, 2.27)	0.62 (0.40, 0.95)	0.11	0.77 (0.48, 1.24)	0.96 (0.49, 1.87)	0.52
MBzP
Tertile 1	1.00	1.00	—	1.00	1.00	—
Tertile 2	0.84 (0.36, 2.12)	1.18 (0.65, 2.12)	—	1.22 (0.61, 2.46)	1.30 (0.53, 3.18)	—
Tertile 3	1.15 (0.49, 2.70)	0.73 (0.37, 1.47)	—	1.03 (0.49, 2.15)	0.62 (0.22, 1.77)	—
Ln(MBzP)	1.12 (0.79, 1.61)	0.82 (0.65, 1.12)	0.09	1.02 (0.74, 1.40)	0.88 (0.55, 1.42)	0.76
MEHP
Tertile 1	1.00	1.00	—	1.00	1.00	—
Tertile 2	1.06 (0.45, 2.53)	0.45 (0.23, 0.89)	—	0.84 (0.41, 1.71)	0.92 (0.34, 2.49)	—
Tertile 3	1.02 (0.41, 2.53)	0.57 (0.31, 1.04)	—	0.77 (0.38, 1.57)	0.90 (0.38, 2.11)	—
Ln(MEHP)	1.06 (0.75, 1.52)	0.68 (0.52, 0.89)	0.10	0.83 (0.62, 1.11)	0.89 (0.62, 1.28)	0.95
MEOHP
Tertile 1	1.00	1.00	—	1.00	1.00	—
Tertile 2	1.97 (0.85, 4.56)	1.10 (0.59, 2.04)	—	1.31 (0.66, 2.60)	1.62 (0.61, 4.34)	—
Tertile 3	1.23 (0.46, 3.32)	0.78 (0.42, 1.47)	—	0.64 (0.30, 1.37)	1.52 (0.61, 3.80)	—
Ln(MEOHP)	1.32 (0.91, 1.91)	0.76 (0.56, 1.04)	0.04	0.88 (0.64, 1.22)	1.01 (0.69, 1.47)	0.53
MEHHP
Tertile 1	1.00	1.00	—	1.00	1.00	—
Tertile 2	2.24 (0.96, 5.19)	0.91 (0.49, 1.71)	—	1.30 (0.64, 2.63)	1.46 (0.59, 3.62)	—
Tertile 3	1.24 (0.46, 3.36)	0.83 (0.45, 1.55)	—	0.83 (0.40, 1.75)	1.13 (0.45, 2.83)	—
Ln(MEHHP)	1.25 (0.87, 1.80)	0.82 (0.61, 1.09)	0.04	0.90 (0.66, 1.24)	1.02 (0.70, 1.47)	0.58
MECPP
Tertile 1	1.00	1.00	—	1.00	1.00	—
Tertile 2	1.35 (0.53, 3.44)	0.53 (0.27, 1.04)	—	0.85 (0.41, 1.75)	0.45 (0.15, 1.33)	—
Tertile 3	2.39 (1.01, 5.67)	0.69 (0.39, 1.25)	—	0.93 (0.46, 1.86)	1.29 (0.56, 2.95)	—
Ln(MECPP)	1.40 (0.96, 2.06)	0.71 (0.51, 0.99)	0.01	0.85 (0.59, 1.22)	1.06 (0.71, 1.60)	0.40
Low MWPe
Tertile 1	1.00	1.00	—	1.00	1.00	—
Tertile 2	1.17 (0.49, 2.81)	2.12 (1.16, 3.89)	—	1.79 (0.91, 3.52)	1.74 (0.66, 4.63)	—
Tertile 3	0.83 (0.35, 1.98)	1.06 (0.54, 2.07)	—	0.93 (0.43, 2.01)	0.81 (0.32, 2.09)	—
Ln(Low MWP)	0.94 (0.69, 1.29)	0.97 (0.76, 1.23)	0.55	0.93 (0.70, 1.22)	0.94 (0.68, 1.30)	0.87
High MWPf
Tertile 1	1.00	1.00	—	1.00	1.00	—
Tertile 2	2.33 (1.01, 5.35)	0.76 (0.42, 1.38)	—	1.05 (0.53, 2.11)	1.04 (0.43, 2.49)	—
Tertile 3	1.27 (0.47, 3.44)	0.53 (0.28, 1.01)	—	0.77 (0.37, 1.61)	0.76 (0.30, 1.94)	—
Ln(High MWP)	1.34 (0.90, 2.00)	0.70 (0.49, 0.98)	0.01	0.86 (0.60, 1.23)	1.02 (0.66, 1.56)	0.50
$\mathrm{\Sigma }\text{DEHP}$g
Tertile 1	1.00	1.00	—	1.00	1.00	—
Tertile 2	2.21 (0.95, 5.15)	1.00 (0.55, 1.83)	—	1.25 (0.63, 2.49)	1.17 (0.47, 2.91)	—
Tertile 3	1.43 (0.52, 3.94)	0.70 (0.37, 1.34)	—	0.76 (0.36, 1.63)	1.15 (0.45, 2.93)	—
Ln($\mathrm{\Sigma }\text{DEHP}$)	1.34 (0.91, 1.96)	0.73 (0.53, 1.02)	0.02	0.87 (0.61, 1.24)	1.02 (0.68, 1.51)	0.53

Note: LIBCSP participants diagnosed with breast cancer between 1 August 1996 and 31 July 1997, followed-up for vital status through December 31, 2014. —, no information was collected at that particular examination point; CI, confidence interval; DEHP, di(2-ethylhexyl) phthalate; HR, hazard ratio; MBzP, monobenzyl phthalate; MCNP, monocarboxy-isononyl phthalate; MCOP, monocarboxyoctyl phthalate; MCPP, mono(3-carboxypropyl) phthalate; MECPP, mono(2-ethyl-5-carboxypentyl) phthalate; MEHHP, mono(2-ethyl-5-hydroxyhexyl) phthalate; MEHP, mono(2-ethylhexyl) phthalate; MEOHP, mono(2-ethyl-5-oxohexyl) phthalate; MEP, monoethyl phthalate; MiBP, mono-isobutyl phthalate; MnBP, mono-N-butyl phthalate; MWP, molecular-weight phthalate.

^aTertiles ($\mathrm{\mu }\mathrm{g}/\mathrm{g}$ creatinine) based on distributions among women without breast cancer.

^bAdjusted for age (continuous), education ($<\text{high}\text{school}/\text{high}\text{school}$ graduate, college, and postcollege), menopausal status (pre- vs. postmenopausal), hormone replacement therapy use (never vs. ever), oral contraceptive use (never vs. ever), and receipt of chemotherapy treatment prior to urine sample collection (yes vs. no).

^c${\mathrm{P}}_{\text{Interaction}}$ derived from continuous BMI- and dichotomized ER by continuous phthalate metabolite concentration interactions in the Cox regression models.

^dAdjusted for age (continuous), education ($<\text{high}\text{school}/\text{high}\text{school}$ graduate, college, and postcollege), menopausal status (pre- vs. postmenopausal), hormone replacement therapy use (never vs. ever), body mass index ($<25.0$, 25.0–29.9, and $\ge 30.0{\mathrm{kg}/\mathrm{m}}^2$), oral contraceptive use (never vs. ever), and receipt of chemotherapy treatment prior to urine sample collection (yes vs. no), as appropriate.

^eLow MWP: Creatinine-corrected molar sum of MEP, MnBP, and MiBP (expressed as MEP, molecular weight 194).

^fHigh MWP: Creatinine-corrected molar sum of MBzP, MEHP, MEOHP, MEHHP, MECPP (expressed as MEHP, molecular weight 278).

^g$\mathrm{\Sigma }\text{DEHP}$: Creatinine-corrected molar sum of DEHP metabolites: MEHP, MEOHP, MEHHP, MECPP (expressed as MEHP, molecular weight 278).