Table 5.

Sitting watching TV and sitting at work in 1995 in relation to incidence of breast cancer overall and ER+ and ER breast cancer

All breast cancerER+ breast cancerER breast cancer
h/dCasesPerson-yearsIRRa (95% CI)CasesIRR (95% CI)CasesIRR (95% CI)
TV
 <115872,7481.00 (Ref.)841.00 (Ref.)431.00 (Ref.)
 1–2540236,3421.05 (0.88–1.26)2881.06 (0.83–1.35)1611.18 (0.84–1.65)
 3–4430206,3620.97 (0.80–1.16)2120.90 (0.70–1.17)1281.09 (0.77–1.55)
 5+20586,3671.13 (0.91–1.40)880.94 (0.69–1.28)671.39 (0.94–2.07)
Ptrend = 0.66Ptrend = 0.25Ptrend = 0.24
Work
 <1260110,8371.00 (Ref.)1361.00 (Ref.)711.00 (Ref.)
 1–216470,8111.06 (0.87–1.30)891.06 (0.80–1.39)481.10 (0.76–1.60)
 3–4257105,1761.15 (0.96–1.37)1461.19 (0.94–1.52)560.89 (0.62–1.27)
 5+635301,2211.05 (0.90–1.22)2940.92 (0.74–1.13)2111.19 (0.90–1.57)
Ptrend = 0.68Ptrend = 0.26Ptrend = 0.21
  • aIRRs adjusted for age (single year), time period (questionnaire cycle), BMI (<25, 25–29, ≥30 kg/m2), years of education (≤12, 13–15, 16, ≥17), parity (0, 1, 2, ≥3), vegetable/fruit dietary pattern (quintiles), meat/fried foods dietary pattern (quintiles), and vigorous activity; sitting watching TV adjusted for sitting at work and vice versa.