Table 5.

Postmenopausal obesity and breast cancer risk stratified by hormone receptor expression

First author (reference)Country (study)Cases (n)BMI (kg/m2)*
Risk estimate (95% CI)
Reference groupBMI category
ER+ER−
Sellers (15)United States (IWHS)1,355<22.9022.90-25.041.3 (1.0-1.6)1.4 (0.8-2.2)
25.05-27.431.4 (1.1-1.7)1.4 (0.9-2.3)
27.44-30.691.8 (1.4-2.2)2.0 (1.2-3.2)
30.70+2.0 (1.6-2.5)1.4 (0.8-2.4)
Yoo (40)Japan455ContinuousPer 1 kg/m21.09 (1.05-1.13)1.05 (0.99-1.12)
PR+PR−
Sellers (15)United States (IWHS)1,355<22.9022.90-25.041.3 (1.0-1.7)1.1 (0.8-1.6)
25.05-27.431.5 (1.2-1.9)1.0 (0.7-1.5)
27.44-30.692.0 (1.6-2.5)1.5 (1.0-2.1)
30.70+2.2 (1.7-2.9)1.0 (0.6-1.5)
Yoo (40)Japan455ContinuousPer 1 kg/m21.09 (1.04-1.14)1.07 (1.02-1.11)
ER+/PR+ER−/PR−
Enger (30)United States (LA County)760<21.721.7-23.61.4 (1.0-1.9)1.2 (0.7-2.0)
23.7-27.01.8 (1.3-2.5)0.8 (0.5-1.4)
27.1+2.5 (1.7-3.5)1.2 (0.7-2.1)
Huang (32)United States (CBCS)783<2323-311.1 (0.7-1.8)1.0 (0.6-1.9)
31+1.6 (0.9-3.0)0.8 (0.4-1.7)
Cotterchio (24)Canada (ON)1,86720-25<200.7 (0.4-1.2)1.3 (0.7-2.5)
25.1-271.1 (0.8-1.4)1.1 (0.7-1.6)
27.1+1.6 (1.3-2.0)1.5 (1.1-2.0)
Potter (17)United States (IWHS)610<3030+1.5 (1.1-1.9)0.8 (0.8-2.8)
  • * Current or baseline BMI (kg/m2), except for Enger et al. and Huang et al., who report BMI 1 year prior to interview.

  • ORs were the reported risk estimates for case-control studies and RRs for cohort designs.