Table 3.

Hazard ratio and 95% CIs for all-cause, breast cancer, and cardiovascular disease mortality according to BMI and weight change since diagnosis

CharacteristicCohort
All-cause mortality
Breast cancer mortality
CVD mortality
nDeaths*HR (95% CI)Deaths*HR (95% CI)Deaths*HR (95% CI)
Prediagnosis BMI, kg/m2
Underweight (<18.5)62111.75 (0.94, 3.25)20.93 (0.22, 3.85)44.15 (1.44-12.0)
Normal (18.5-24.9)2,0581781501361
Overweight (25.0-29.9)1,2281371.13 (0.90, 1.42)451.48 (0.98, 2.24)271.05 (0.63, 1.74)
Obese (≥30)639931.52 (1.17, 1.98)241.42 (0.86, 2.36)282.45 (1.46, 4.11)
Postdiagnosis BMI, kg/m2
Underweight (<18.5)42101.57 (0.82, 3.02)11.10 (0.15, 8.09)10.58 (0.08, 4.34)
Normal (18.5-24.9)1,4971401311301
Overweight (25.0-29.9)1,3731330.91 (0.72, 1.16)371.34 (0.83, 2.18)300.99 (0.59, 1.66)
Obese (≥30)9771221.27 (0.99, 1.64)482.28 (1.43, 3.64)291.65 (0.97, 2.83)
Weight change since diagnosis, kg
−50 to −10.1114332.66 (1.73, 4.07)20.64 (0.15-2.79)61.08 (0.42, 2.78)
−10.0 to −2.1608931.39 (1.04, 1.86)140.90 (0.47, 1.72)241.02 (0.58, 1.80)
−2.0 to 2.01,037981281271
2.1 to 6.01,127880.98 (0.73, 1.31)300.98 (0.58, 1.65)180.79 (0.43, 1.44)
6.1 to 10.0555481.06 (0.75, 1.51)201.28 (0.71, 2.31)80.64 (0.29, 1.44)
10.1 to 103552611.70 (1.21, 2.41)271.78 (1.01, 3.14)121.73 (0.83, 3.62)
5-kg Decrease§1.24 (1.07, 1.43)0.79 (0.42-1.47)1.02 (0.75, 1.40)
5-kg Increase1.12 (1.04, 1.22)1.13 (1.03, 1.25)1.19 (1.01, 1.40)
  • Abbreviations: HR, hazard ratio; CVD, cardiovascular disease.

  • * Total numbers of deaths vary slightly in pre- and postdiagnosis BMI models compared with weight change models based on missing values for height that did not allow for BMI to be calculated.

  • Hazard ratio adjusted for age, state, time between diagnosis and follow-up interview, family history of breast cancer, cigarette smoking, total recreational physical activity at follow-up, menopausal status, and stage.

  • Additionally adjusted for prediagnosis weight.

  • § Analysis restricted to women who reported staying within 2 kg of their prediagnosis weight or losing weight.

  • Analysis restricted to women who reported staying within 2 kg of their prediagnosis weight or gaining weight.