Circulating prolactin and in situ breast cancer risk in the European EPIC cohort: a case-control study

Breast Cancer Research

Table 3 Adjusted odds ratios ^a (OR) for in situ breast cancer on a continuous log ₂ scale of circulating prolactin by subgroup analysis

	Case-control sets, number	Log ₂ odds ratio (95% CI)	P _trend ^b	P _het ^c
All women
Lag time till diagnosis
<4 years	127	1.78 (1.12, 2.84)	0.01	0.04
≥4 years	180	1.09 (0.77, 1.55)	0.63
Parity^d
Nulliparous	42/45	2.64 (1.07, 6.51)	0.03	0.07
Parous	251/251	1.21 (0.94, 1.57)	0.15
Premenopausal women
Lag time till diagnosis
<4 years	39	2.30 (0.85, 6.14)	0.10	0.15
≥4 years	47	0.97 (0.51, 1.83)	0.92
Postmenopausal women (all)
Lag time till diagnosis
<4 years	88	1.66 (0.97, 2.85)	0.07	0.19
≥4 years	133	1.18 (0.76, 1.82)	0.46
Parity^d
Nulliparous	29/32	5.10 (1.23, 21.15)	0.02	0.02
Parous	187/185	1.22 (0.88, 1.68)	0.24
Postmenopausal non-HT users
Lag time till diagnosis
<4 years	52	1.20 (0.70, 2.05)	0.51	0.52
≥4 years	87	1.08 (0.61, 1.93)	0.79
Postmenopausal HT users
Lag time till diagnosis
<4 years	36	6.02 (1.31, 27.72)	0.02	0.04
≥4 years	46	1.29 (0.64, 2.61)	0.47

^aAdjusted for parity (nulliparous, parous, missing data), smoking status (current, never, previous, or missing data) and body mass index (continuous scale); ^blinear trends for odds ratio estimates over a continuous scale of prolactin levels; ^cheterogeneity between subgroups was based on the chi-square test; ^dusing unconditional logistic regression, adjusted for age and time at blood donation, fasting and smoking status, body mass index, phase of menstrual cycle for premenopausal women and current use of hormone therapy (HT) for postmenopausal women.

ISSN: 1465-542X