Association between Antibiotic Use and Subsequent Risk of Breast Cancer: A Nationwide Retrospective Cohort Study in South Korea

Menée à partir de données de l'Assurance maladie coréenne portant sur 4 097 812 femmes, cette étude analyse l'association entre la durée d'utilisation d'antibiotiques et le risque de cancer du sein

Résumé en anglais

Several studies have revealed a possible association between antibiotic use and breast cancer in the Western population of women. However, its association with the Asian population remains unclear. Data utilized in this nationwide population-based retrospective cohort study was obtained from the Korean National Health Insurance Service (NHIS) database. The study population consisted of 4,097,812 women who were followed up from January 1, 2007, to December 31, 2019. Cox proportional hazards regression was utilized to calculate adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs) for the risk of breast cancer according to cumulative days of antibiotic use and the number of antibiotic classes used. It was discovered that women who used antibiotics for more than 365 days had a higher risk of breast cancer (aHR, 1.15; 95% CI, 1.09-1.21) in comparison to those who did not use antibiotics. In addition, an association was found among women who used five or more classes of antibiotics, showing a higher risk of breast cancer (aHR, 1.11; 95% CI, 1.05-1.17) compared to non-users. Furthermore, compared to antibiotic non-users, only users of cephalosporins (aHR 1.09; 95% CI, 1.02-1.17) and lincosamides (aHR 1.70; 95% CI, 1.20-2.42) had a higher risk of breast cancer. These findings support epidemiological evidence that long-term use of antibiotics may be associated with a higher risk of breast cancer. This underscores the need for further studies to address the potential for residual confounding, confirm causation, and elucidate the underlying mechanisms.