Nonsteroidal anti‐inflammatory drug use and breast cancer risk in a European prospective cohort study

• Published in: International journal of cancer Vol. 143; no. 7; pp. 1688 - 1695
• Main Authors: Cairat, Manon, Fournier, Agnès, Murphy, Neil, Biessy, Carine, Scalbert, Augustin, Rinaldi, Sabina, Tjønneland, Anne, Olsen, Anja, Overvad, Kim, Arveux, Patrick, Boutron‐Ruault, Marie‐Christine, Cadeau, Claire, Fortner, Renée Turzanski, Kaaks, Rudolf, Boeing, Heiner, Aleksandrova, Krasimira, Peeters, Petra H.M., Van Gils, Carla H., Wareham, Nicholas J., Khaw, Kay‐Tee, Aune, Dagfinn, Riboli, Elio, Gunter, Marc J., Dossus, Laure
• Format: Journal Article
• Language: English
• Published: United States Wiley Subscription Services, Inc 01.10.2018; Wiley
• Subjects: Adult; Aged; Anti-Inflammatory Agents, Non-Steroidal - adverse effects; Breast cancer; Breast Neoplasms - chemically induced; Breast Neoplasms - epidemiology; Breast Neoplasms - pathology; Cancer; chemoprevention; Cohort analysis; cohort studies; Drug abuse; Drug development; Europe - epidemiology; Female; Follow-Up Studies; Health risk assessment; Health risks; Hormone replacement therapy; Humans; Incidence; Inflammation; Invasiveness; Life Sciences; Medical research; Middle Aged; Nonsteroidal anti-inflammatory drugs; nonsteroidal anti‐inflammatory agents; Post-menopause; postmenopausal hormone replacement therapy; Prognosis; Prospective Studies; Regression analysis; Risk Factors; Statistical analysis; Europe; postmenopausal hormone replacement therapy; cohort studies; breast cancer; chemoprevention; nonsteroidal anti-inflammatory agents
• ISSN: 0020-7136; 1097-0215
• DOI: 10.1002/ijc.31570

Experimental studies have shown a protective effect of nonsteroidal anti‐inflammatory drugs (NSAIDs) on breast cancer development. However, results from epidemiological cohort studies are less consistent. Our objective was to assess the association between NSAID use and breast cancer risk within the European Prospective Investigation into Cancer and Nutrition (EPIC). EPIC is a prospective cohort study initiated in 1992 in 10 European countries. Self‐reported information on NSAID use at baseline has been collected in five EPIC countries. Multivariable Cox regression models were used to estimate hazard ratios for the association of NSAID use with breast cancer incidence with adjustment for potential confounders. We also assessed effect modification by breast cancer risk factors and examined the associations within specific breast cancer subtypes. Among the 140,981 women included in the analysis, 7% were regularly using NSAIDs at baseline. During a median follow‐up time period of 13 years, 7,379 incident breast cancer cases were diagnosed (816 in situ and 6,563 invasive). There were no statistically significant associations between NSAID use and breast cancer risk, overall and by subtypes. However, a statistically significant interaction was observed for invasive cases between NSAID use and ever use of menopausal hormonal therapy (MHT) among postmenopausal women [MHT users: HRNSAID use = 0.84 (0.73–0.96); non MHT users: HRNSAID use = 1.08 (0.93–1.25); pinteraction = 0.05]. Our results indicate potential effect modification of MHT use on the association between use of NSAIDs and breast cancer risk which deserves in‐depth investigation in studies with accurate data on both NSAID and MHT use. What's new? Chronic inflammation is a suspected factor in breast cancer development. Hence, the possibility of stemming tumorigenic inflammatory effects with nonsteroidal anti‐inflammatory drugs (NSAIDs) has drawn significant interest. Here, using data from the European Prospective Investigation into Cancer and Nutrition prospective cohort study, the authors reveal an association between NSAID use and decreased risk of invasive breast cancer specifically in postmenopausal women who ever used menopausal hormonal therapy (MHT). No association was found between NSAID use and breast cancer risk in non‐MHT users. Additional investigation is needed to better understand interactions between MHT use, NSAIDs, and breast cancer risk.