Nonsteroidal anti-inflammatory drug and aspirin use in relation to lung cancer risk among postmenopausal women

Background: Results from prospective studies suggest that nonsteroidal anti-inflammatory drugs (NSAID) may decrease lung cancer risk; however, any protective effect appears to be most evident in men. Methods: We evaluated the associations between NSAID use and lung cancer incidence in postmenopausal women in the Women's Health Initiative (WHI) adjusting for female-specific potential confounders such as hormone therapy in addition to smoking histories and other potential confounders. We identified 143,841 women from ages 50 to 79 and 1,902 centrally confirmed lung cancer cases were included in the analysis. We used Cox regression models to estimate HRs and their 95% confidence intervals (CI). Results: Compared with nonuse, regular NSAID use was not associated with overall lung cancer incidence (NSAID use >10 years HR 0.87; 95% CI, 0.71-1.08, P_trend= 0.13). No statistically significant associations were found when examined by histologic subtypes and although there was a trend of decreased risk with longer duration of NSAID use in the adenocarcinoma subtype, this was not statistically significant (NSAID use >10 years HR 0.80; 95% CI, 0.58-1.10; P_trend= 0.07). Conclusion: Our study did not show that NSAID use is associated with lung cancer risk in women even after adjusting for female-specific confounders. There was a trend of decreased risk in the adenocarcinoma subtype; however, this was not statistically significant. Impact: Future studies will need to take in account the various molecular subtypes of non-small cell lung cancer to further elucidate the role of NSAIDs in lung cancer, especially for the adenocarcinoma subtype.