OBJECTIVE: To estimate the impact of treatment with middle ear ventilation tube insertion (VTI) in children with otitis media (OM) on the risk of cholesteatoma on a national level.

METHODS: Data were obtained from the Danish National Patient Register, the National Health Service Register and Statistics Denmark. Cumulative incidence proportions were estimated by the Kaplan-Meier method and hazard ratios with Cox regression analysis. The first surgically treated middle ear cholesteatoma in a child (STMEC1) was considered an event.

RESULTS: A total of 217,206 children, born after December 31, 1996, who had VTI from January 1, 1997 to August 31, 2011 were identified. Of these, 374 subsequently had a STMEC1. A corresponding 36,981 children without any VTI were identified for comparison using a random 5% sample of the Danish population. Of these, 5 had a STMEC1. The cumulative incidence proportion with STMEC1 at 12 years of age for children with 0, 1, 2, 3, and ≥4 VTI's was 0.04% (95% confidence interval 0.02-0.12%), 0.21% (0.18-0.26%), 0.35% (0.28-0.43%), 0.40% (0.30-0.54%), and 0.55% (0.44-0.70%), respectively. In the regression model each additional year of age before the first VTI increased the risk of STMEC1 by 54% (47-63%), while each additional year between two successive tube insertions increased the risk by 28% (15-43%).

CONCLUSION: We found that prolonged OM requiring multiple VTIs was associated with an increased risk of STMEC1. Early age at first VTI and short time between two VTIs was associated with a lower risk of STMEC1. This may be the result of reduced time with negative middle ear pressure and OM. However, these findings may be susceptible to selection bias, as age at first VTI and time between VTIs, as well as the outcome variable, STMEC1, may all depend on the underlying indication for VTI. In short the present study suggests that treatment with VTI in children with OM reduces the risk of STMEC1 on a population level. However, for the individual child the absolute risk reduction is very small, and the decision of treatment with VTI must always rely on the symptoms and clinical findings in the individual child.