Tonsillectomy Does Not Reduce Upper Respiratory Infections: A National Cohort Study

OBJECTIVES The objective of this study was to compare post-operative visits for upper respiratory infections (URIs) between tonsillectomy and non-tonsillectomy participants (controls). METHODS Using the national cohort study from the Korean Health Insurance Review and Assessment Service, 1:4 matched (age, sex, income, region, and pre-operative URI visit) tonsillectomy participants (5,831) and control participants (23,324) were selected. Post-operative visits for URI were measured from 1 to 9 years post-op. The equivalence test was used. The margin of equivalence of the difference (Tonsillectomy-Control group group) was set to -0.5 to 0.5. RESULTS There was no difference between the tonsillectomy and control group in 1- to 9-year post-op visits (-0.5 < 95% CI of difference < 0.5). URI visits gradually decreased from 5.5/2 years (pre-op) to 2.1/year (at 1 year post-op) and 1.4/year (at 9 years post-op) in both tonsillectomy and control groups. In the subgroup analysis (children Vs adolescent and adults; rare Vs frequent pre-operative URI), there was no difference in the number of post-op visits for URI between the tonsillectomy and control groups (-0.5 < 95% CI of difference < 0.5). CONCLUSION Tonsillectomy does not provide a decrease in the number of post-operative visits for URI, and URI decreased over time whether or not a tonsillectomy was performed.