Table 3

Rate ratios (RR) of breast cancer incidence according to weight gain from age 18 years to 1992 stratified by hormone replacement therapy (HRT) use in 1992 in the Cancer Prevention Study-II Nutrition Cohort, 1992–1999

Adult weight gain (in pounds) from age 18 years to 1992P
−5 to 56 to 1011 to 2021 to 3031 to 4041 to 5051 to 6061 to 7071+
Non-HRT users
 No. cases96781702181691539281125
 Age-standardized rate371.4378.7375.1472.4432.1546.0475.2640.2708.7
 Age-adjusted RRa1.001.061.011.301.181.461.301.801.92
 95% CI0.79–1.430.79–1.301.02–1.650.92–1.521.13–1.890.98–1.731.34–2.431.47–2.51
 Multivariate RRb1.001.071.031.341.241.551.391.962.08<0.0001
 95% CI0.80–1.450.80–1.321.05–1.700.96–1.591.20–2.011.04–1.851.46–2.641.59–2.73
 Multivariate RRc1.001.091.071.421.311.601.391.942.13<0.0001
 95% CI0.81–1.470.83–1.381.10–1.830.99–1.721.20–2.131.00–1.931.37–2.751.50–3.01
Current HRT users
 No. cases1098117312510965371934
 Age-standardized rate636.7608.9649.9548.3532.7528.8521.7486.2693.1
 Age-adjusted RRa1.001.000.980.800.900.790.740.681.00
 95% CI0.75–1.330.77–1.250.62–1.040.69–1.170.58–1.080.51–1.080.42–1.100.68–1.47
 Multivariate RRb1.001.011.000.840.960.850.820.731.110.35
 95% CI0.76–1.340.79–1.280.65–1.090.73–1.250.62–1.160.57–1.200.45–1.190.75–1.64
 Multivariate RRc1.001.021.040.891.020.880.830.721.130.53
 95% CI0.77–1.360.81–1.330.68–1.170.76–1.360.63–1.240.55–1.250.43–1.210.72–1.76
  • a RR adjusted for age at interview.

  • b RR adjusted for age at interview, age at menarche, age at menopause, number of live births, age at first live birth, oral contraceptive use, family history of breast cancer, history of breast cysts, history of mammography, height, education, physical activity, alcohol use, and race.

  • c RR adjusted for BMI in 1992 in addition to all covariates listed above.