How many tonsillectomies are necessary? An eleven year retrospective cohort study of indications and eligibility for childhood tonsillectomy in UK primary care

Problem

Tonsillectomy is one of the most common childhood surgical procedures. It has long been the poster-boy for overtreatment, with wide national and international variations in the use of the procedure. Evidence based indications for tonsillectomy include: documented sore throats of sufficient frequency and severity (7 in one year, 5 yearly in two successive years or 3 yearly for three successive years - Paradise criteria), aphthous stomatitis, pharyngitis and cervical adenitis syndrome (PFAPA), or tonsillar tumour. As far as we are aware, our analysis for the first time describes the incidence of evidence based indications for tonsillectomy in UK children, proportion of children with evidence based indications who actually undergo tonsillectomy and the proportion of tonsillectomies that are evidence based.

Approach

We analysed electronic medical records of 1.5 million UK children aged 0-15 years registered with one of 688 UK general practices contributing to a research database (The Health Improvement Network) between 2005-2015. We identified children with recorded evidence based indications for tonsillectomy and we determined the proportion subsequently undergoing tonsillectomy. We also identified children who had undergone tonsillectomy and identified the indications for surgery. From this we calculated the proportion with evidence based indications.

Findings

Between 2005 and 2015, on average 4.3 children per 1,000 person years annually met evidence based criteria for tonsillectomy: 13.2% (1,915/14,528) underwent tonsillectomy. Of children undergoing tonsillectomy, 12.0% (1,915/16,015) had an evidence based indication: 99.3% (1,902/1,915) meeting the Paradise criteria. Most (79.0% 12,649/16,015) tonsillectomies were undertaken in children with insufficient documented sore throats although only a tiny proportion of such children underwent tonsillectomy.

Consequences

The great majority of children with evidence based indications for tonsillectomy never have surgery. The great majority of children undergoing tonsillectomy do not have evidence based indications. We have convincingly demonstrated dramatic overuse alongside potential underuse of one of the most common surgical procedures of childhood. Parents of children meeting Paradise criteria should be informed that tonsillectomy potentially offers only modest benefits and that seven in eight children meeting these criteria do not have tonsillectomy. Parents of less severely affected children should be informed that tonsillectomy is ineffective and that the vast majority of similarly affected children do not undergo tonsillectomy.