Table 3.

Association of postdiagnosis weight change and all-cause and breast cancer–specific mortality by age and stage

# Events/NLarge loss (≥10%)Modest loss (>5%–<10%)Stable (within 5%)Modest gain (>5%–<10%)Large gain (≥10%)Pinteraction
HR (95% CI)
Breast cancer–related death
 Age at diagnosis
  <55 years181/4,8562.43 (1.51–3.09)1.69 (1.10–2.57)Ref.0.78 (0.49–1.24)1.10 (0.66–1.84)0.04
  >55 years322/7,7342.10 (1.54–2.86)1.04 (0.75–1.46)Ref.1.40 (0.97–2.02)0.84 (0.46–1.51)
 Stage
  III187/1,2582.22 (1.47–3.37)1.68 (1.13–2.49)Ref.0.90 (0.50–1.60)1.39 (0.78–2.47)0.24
  II229/4,3782.42 (1.65–3.54)1.21 (0.82–1.81)Ref.1.10 (0.73–1.65)0.84 (0.47–1.50)
  I87/6,9541.37 (0.67–2.84)0.41 (0.16–1.03)Ref.1.12 (0.61–2.05)0.61 (0.19–1.99)
All-cause death
 Age at diagnosis
  <55 years243/4,8562.95 (2.01–4.34)1.57 (1.08–2.28)Ref.0.69 (0.45–1.05)1.12 (0.72–1.75)0.02
  >55 years737/7,7342.21 (1.80–2.72)1.05 (0.84–1.31)Ref.1.10 (0.86–1.40)0.88 (0.60–1.29)
 Stage
  III240/1,2582.16 (1.49–3.14)1.65 (1.16–2.35)Ref.0.91 (0.55–1.50)1.42 (0.87–2.34)0.01
  II401/4,3782.45 (1.86–3.25)1.13 (0.83–1.52)Ref.0.84 (0.60–1.17)0.78 (0.50–1.23)
  I339/6,9542.48 (1.80–3.42)0.80 (0.55–1.15)Ref.1.07 (0.77–1.50)0.86 (0.48–1.55)
  • NOTE: Adjusted for age at diagnosis (continuous), race, smoking status, alcohol intake, stage (in BMI subgroup), grade, comorbidities, tumor characteristics, receipt of adjuvant chemotherapy (yes/no), receipt of radiotherapy (yes/no), and prediagnosis BMI. Pinteraction from likelihood ratio test comparing models with and without interaction terms of weight change category and each subgroup variable.