Association between common allergic symptoms and cancer in the NHANES III female cohort.

Background: Previous epidemiological studies have investigated the association between allergic symptoms and cancer occurrence. However, the role of allergy in cancer has been elusive, especially for the female population.

Methods: We examined the relationship between cancer prevalence and common allergic symptoms of rhinoconjunctivitis (RC) and wheezing (WZ) among NHANES III female participants.

Results: Among 4600 people, 36.3% (n = 1669) did not have any allergic symptoms (NO), while 47.6% (n = 2188) reported RC, and 16.2% (n = 743), WZ. The proportion of cancer among NO groups was 5.43% (91/1669), among RC group, 7.63% (167/2188), and among WZ group, 11.23% (83/743) (RC group- OR 1.44 with 95% CI 1.00-2.08; p = 0.05 while for WZ group- OR 2.20 with 95%CI 1.27-3.80; p = 0.01). After adjusting for all the possible confounding variables including age, smoking, or COPD, having symptoms of RC (AOR 1.49 with 95%CI 1.12-2.36; p = 0.01) or WC (AOR 2.08 with 95%CI 1.11-3.89; p = 0.02) demonstrated consistent strong association with cancer. Among nonsmokers (n = 2505, 54.5%) only symptoms of RC showed association with cancer (AOR 1.51 with 95%CI 1.00-2.28; p = 0.05). Among former or current smokers (n = 2094, 45.5%), only symptoms of WZ demonstrated association with cancer (AOR 2.38 with 95%CI 1.16-4.87; p = 0.02). Among different types of cancers, odds of having breast cancer among participants with symptoms of RC or WZ were approximately twice the odds of having breast cancer among participants without any of these symptoms. AOR for RC group was 1.89 with 95%CI 1.04-3.42 and p = 0.04 while AOR for WC group was 2.08 with 95%CI 0.90-4.78 and p = 0.08.

Conclusions: In summary, we found associations between common allergic symptoms like rhinitis/conjunctivitis and wheezing and prevalence of cancer, specifically between rhinitis/conjunctivitis and breast cancer that were not found in previous studies. Larger prospective studies are required to validate our findings.