Association of adenotonsillectomy with asthma and upper respiratory infection: A nationwide cohort study.

Adenotonsillectomy is a common paediatric surgery for treating obstructed breathing or recurrent inflammation; however, the long-term health consequences on the developing immune system are unknown. This study investigated the potential association between adenotonsillectomy and the development of asthma and upper respiratory infections (URI). This propensity score-matched retrospective cohort study utilized data from the National Sample Cohort 2002-2013. In the asthma cohort, we used a Cox-proportional hazards model to analyze the hazard ratio (HR) of adenotonsillectomy for asthma events. In the URI cohort, equivalence testing of postoperative visits for URI was performed. The margin of equivalence of the difference was set at -0.5-0.5. Asthma incidence was 66.97/1000 person-years in children who underwent adenotonsillectomy and 30.43/1000 person-years in those who did not. Adjusted asthma HRs were 2.25 (95% confidence interval, 1.96-2.57) in the adenotonsillectomy vs. non-adenotonsillectomy groups. In a subgroup analysis, children aged 5-9 years living in metropolitan areas showed a higher incidence of subsequent asthma than those of other ages and areas. However, any significant difference between the groups in terms of URI events in the 1-11-year postoperative period was not identified. Adenotonsillectomy in children is associated with an increased incidence of asthma, with no significant impact on postoperative visits for URI.