Adenotonsillectomy for upper respiratory infections: evidence based?

BACKGROUND Despite high rates of (adeno)tonsillectomy for upper respiratory infections in western countries, the medical literature offers the physician little support in deciding which child might benefit from the operation. METHODS A literature search was performed to identify randomised trials and non-randomised controlled studies into the efficacy of tonsillectomy with or without adenoidectomy in children under 18 years. For the outcomes sore throat episodes, sore throat associated school absence, and upper respiratory infections, pooled estimates of the incidence rate ratios and rate differences with 95% confidence intervals were calculated, assuming a Poisson distribution. RESULTS Six randomised trials and seven non-randomised controlled studies on the efficacy of adenotonsillectomy in children were evaluated. For sore throat episodes data for 2483 person-years were available. The pooled risk difference was -1.2 episodes per person-year (95% CI -1.3 to -1.1). For sore throat associated school absence 1669 person-years were analysed. The pooled risk difference was -2.8 days per person-year (95% CI -3.9 to -1.6). For upper respiratory infections 1596 person-years were available. The pooled risk difference was -0.5 episodes per person-year (95% CI -0.7 to -0.3). CONCLUSIONS All available randomised trials and non-randomised controlled studies into the efficacy of (adeno)tonsillectomy had important limitations. The frequency of sore throat episodes and upper respiratory infections reduces with time whether (adeno)tonsillectomy has been performed or not. (Adeno)tonsillectomy gives an additional, but small, reduction of sore throat episodes, days of sore throat associated school absence, and upper respiratory infections compared to watchful waiting.