TABLE 2.

Odds ratios and 95% confidence intervals for factors modifiable after menopause in relation to postmenopausal invasive breast cancer risk, Wisconsin, Massachusetts, and New Hampshire, 1997–2001

Factor	No. of controls	%*	No. of cases	%*	OR†‡	95% CI†	OR§	95% CI
Postmenopausal hormone use (type and duration)
Never	2,125	50.4	1,583	45.2	0.95	0.80, 1.12	0.92	0.77, 1.10
Former	364	8.6	283	8.1	1	Reference	1	Reference
Current estrogen only	839	19.9	651	18.6	0.98	0.81, 1.18	0.96	0.79, 1.17
Current estrogen + progestin	638	15.1	741	21.2	1.48	1.23, 1.79	1.31	1.07, 1.60
Current other/unknown	198	4.7	191	5.5	1.25	0.97, 1.61	1.08	0.83, 1.41
Recent alcohol consumption (drinks/week)¶
<1.0	2,364	56.1	1,819	52.0	1	Reference	1	Reference
1.0–6.9	1,253	29.7	1,099	31.4	1.14	1.03, 1.26	1.12	1.00, 1.24
7.0–13.9	400	9.5	358	10.2	1.19	1.02, 1.39	1.14	0.96, 1.34
≥14.0	164	3.9	189	5.4	1.51	1.22, 1.88	1.43	1.14, 1.80
Weight change since age 18 years (kg)
Lost >5	123	2.9	85	2.4	1.02	0.75, 1.37	1.09	0.79, 1.49
Lost ≤5–gained ≤5	770	18.3	521	14.9	1	Reference	1	Reference
Gained 5.1–15	1,282	30.4	1,079	30.8	1.24	1.08, 1.43	1.27	1.10, 1.47
Gained 15.1–30	1,445	34.3	1,269	36.3	1.28	1.12, 1.47	1.36	1.18, 1.56
Gained >30	455	10.8	456	13.0	1.47	1.24, 1.75	1.67	1.39, 2.00
Recent recreational physical activity (hours/week)#
0	1,565	37.2	1,325	37.9	1.17	0.92, 1.50	1.26	0.98, 1.61
0.1–2.0	1,732	41.1	1,417	40.5	1.13	0.88, 1.43	1.15	0.90, 1.48
2.1–5.0	722	17.1	616	17.6	1.17	0.90, 1.51	1.17	0.90, 1.53
>5.0	172	4.1	125	3.6	1	Reference	1	Reference

^*Because of missing data, some categories do not sum to 100%. N = 3,499 cases and 4,213 controls.

^†OR, odds ratio; CI, confidence interval.

^‡Adjusted for age and state of residence.

^§Adjusted for age, state of residence, weight at age 18 years, screening mammograms per year over the last 5 years, and all variables in tables 1 and 2.

^¶Over the past year.

^#Averaged over the period 6 years to 1 year prior to the participant's reference date.