Abstract B94: Hay fever and asthma as markers of atopic immune response and risk of colorectal cancer in three large cohort studies

Background: In a previous analysis of the Cancer Prevention Study II (CPS-II) cohort that included follow-up from 1982-2000, having both hay fever and asthma was associated with lower colorectal cancer mortality. The combination of these allergy-related conditions may be a marker for allergy-related immune responses that could inhibit the development or progression of colorectal cancer.

Methods: We examined the association between having both hay fever and asthma and colorectal cancer mortality among 1,023,191 participants in Cancer Prevention Study I (CPS-I) followed-up from 1959-1972, and 1,102,092 participants in CPS-II, now followed-up from 1982 through 2008. We also examined associations with colorectal cancer incidence among 174,917 participants in the CPS-II Nutrition Cohort, a subgroup of CPS-II followed from 1992-2007. During follow-up, there were 5,644 colorectal cancer deaths in CPS-I, 13,558 colorectal cancer deaths in CPS-II, and 3,365 incident colorectal cancers in the CPS-II Nutrition Cohort. Cox proportional hazards regression models were used to calculate multivariable-adjusted relative risks (RRs).

Results: RRs for colorectal mortality associated with having both asthma and hay fever, compared to neither condition, were 0.90 (95% confidence interval (CI): 0.74-1.09) in CPS-I, 0.79 (95% CI: 0.69-0.91) in CPS-II, and 0.83 (95% CI: 0.74-0.92) when results from both cohorts were combined using a fixed-effects meta-analysis. The RR for colorectal cancer incidence in the CPS-II Nutrition Cohort was 0.90 (95% CI: 0.71-1.14).

Conclusion: These results are consistent with an association between having both hay fever and asthma and modestly lower colorectal cancer mortality.

Citation Format: Eric J. Jacobs, Susan M. Gapstur, Christina C. Newton, Michelle C. Turner, Peter T. Campbell. Hay fever and asthma as markers of atopic immune response and risk of colorectal cancer in three large cohort studies. [abstract]. In: Proceedings of the Eleventh Annual AACR International Conference on Frontiers in Cancer Prevention Research; 2012 Oct 16-19; Anaheim, CA. Philadelphia (PA): AACR; Cancer Prev Res 2012;5(11 Suppl):Abstract nr B94.