Table 4

RR of breast cancer associated with recent use of postmenopausal hormones (within 5 years of the reference age) and duration of use ≥5 years versus never use

Estrogen onlyEstrogen with progestin only
CasesControlsRRa (95% CI)PbCasesControlsRRa (95% CI)Pb
Overall4894771.39 (1.17–1.65)114931.57 (1.15–2.14)
Reference age (yrs)
 50–591331701.49 (1.12–1.98)66481.91 (1.25–2.90)
 60–692221981.41 (1.11–1.80)41361.35 (0.82–2.23)
 70–791341091.27 (0.95–1.71)0.4790.88 (0.31–2.49)0.01
Body mass index quartile (kg/m2)
 1 (13.2–22.6)1261271.66 (1.22–2.25)33301.74 (1.00–3.04)
 2 (22.7–25.3)1211231.26 (0.93–1.72)32291.51 (0.87–2.64)
 3 (25.4–29.0)1091221.17 (0.85–1.60)19141.35 (0.63–2.89)
 4 (29.1–56.7)110831.46 (1.04–2.05)0.324161.50 (0.76–2.98)0.8
Family history
 No3914131.39 (1.16–1.67)91761.67 (1.18–2.35)
 Yes94631.33 (0.91–1.93)0.823171.25 (0.64–2.44)0.9
Recent alcohol intake (drinks/day)
 None96851.71 (1.21–2.42)12111.35 (0.56–3.27)
 <13063061.46 (1.19–1.79)75671.49 (1.03–2.16)
 ≥186860.94 (0.65–1.35)0.0727152.08 (1.05–4.11)0.2
Self-reported screening mammography in the past 5 yrs
 Never40261.19 (0.69–2.06)041.59 (0.90–2.83)c
 Less than annual1661841.63 (1.26–2.11)2628
 At least annually2802661.27 (1.02–1.58)0.867811.56 (1.08–2.24)0.3
  • a Relative to nonusers (3827 cases and 4132 controls). Logistic regression models were conditional on age and state. RR was adjusted for age at menopause, type of menopause, age at first full-term pregnancy, body mass index, family history of breast cancer, education, history of screening mammography, recent alcohol consumption, history of benign breast disease, age at menarche, and recent physical activity. Women who used both unopposed estrogen and estrogen-progestin are excluded.

  • b Evaluated continuously when appropriate with hormone use represented by a continuous linear duration term. Tests include users with all durations and timings of use.

  • c Estimate for mammography never and less than annually combined.