Table 6.

Multivariable-adjusted relationship between hormone receptor-defined breast cancer and occupational household, walking, or cycling activity among postmenopausal women, SBCS, 1996-1998

VariableControls (n)ER+/PR+
ER−/PR−
ER+/PR−
ER−/PR+
nOR (95% CI)nOR (95% CI)nOR (95% CI)nOR (95% CI)
Occupational activity
    Sitting time *5591781.00 (1.00-1.01)731.00 (0.99-1.01)350.99 (0.98-1.01)321.00 (0.98-1.01)
    Walking time (hours a day)5531760.91 (0.85-0.97)721.00 (0.92-1.10)350.94 (0.82-1.07)321.03 (0.90-1.18)
    Activity self-rating5591781.00 (0.99-1.00)731.00 (0.99-1.01)350.99 (0.98-1.01)320.99 (0.97-1.01)
    Average energy expenditure5591781.00 (0.99-1.01)731.00 (0.99-1.01)351.00 (0.99-1.02)321.00 (0.98-1.02)
Other activity
    Ages 13-19 y
        Household (hours a day)5591770.98 (0.90-1.07)730.96 (0.85-1.10)350.90 (0.74-1.12)320.69 (0.51-0.93)
        Walking (minutes a day)5581780.99 (0.99-1.00§)721.00 (0.99-1.00)351.00 (0.99-1.00)321.00 (0.99-1.01)
    Last 10 y
        Household (hours a day)5581781.03 (0.93-1.15)731.22 (1.07-1.40)351.02 (0.82-1.27)320.92 (0.72-1.18)
        Walking (minutes a day)5591781.00 (0.99-1.00)731.00 (0.99-1.00)351.00 (0.99-1.01)320.99 (0.98-1.00)
  • NOTE: Adjusted for current age, age at first menarche, age at first birth, age at menopause, and breast-feeding; each exercise variable represents a separate polytomous logistic model.

  • * Sitting time calculated as sum of (sitting category for job classification × no. years on job) across all jobs.

  • Activity self-rating calculated as sum of (activity category × no. years on job) across all jobs.

  • Average energy expenditure calculated as sum of (energy expenditure category × no. years on job) across all jobs.

  • § 95% CI includes null, but Ps ≤ 0.05.

  • P > 0.05 and P ≤ 0.10.