Table 2.

Age- and multivariate-adjusted HRs for incident colorectal cancer in relation to history of allergy, IWHS 1997-2004

Allergy characteristicsNo. casesPerson-yearsAge-adjusted HR (95% CI)Multivariate-adjusted* HR (95% CI)
No allergy309109,2521 (reference)1 (reference)
Allergy10149,6780.73 (0.58-0.91)0.74 (0.59-0.94)
Except asthma7136,2220.70 (0.54-0.91)0.73 (0.56-0.95)
Asthma2511,6580.77 (0.51-1.15)0.77 (0.50-1.16)
Hay fever2912,9080.82 (0.56-1.19)0.81 (0.54-1.20)
Skin allergies3719,9430.68 (0.48-0.96)0.70 (0.49-0.98)
Other allergies5127,9100.66 (0.49-0.98)0.69 (0.51-0.92)
No. allergies in a person
    0309109,2521 (reference)1 (reference)
    15426,7120.73 (0.54-0.97)0.75 (0.56-1.01)
    ≥22213,8320.58 (0.38-0.89)0.58 (0.37-0.90)
P trend0.010.02
  • * Adjusted for age, pack-years, total energy intake, calcium, red meat, and multivitamin use in 1986, BMI in 1997, and diabetes and HRT use before 1997.

  • For this analysis, only women who answered all four specific allergy questions were included.