Bjarki Ditlev Djurhuus

Increasing rate of middle ear ventilation tube insertion in children in denmark

OBJECTIVE To study the incidence rates of middle ear ventilation tube insertion in children aged 0 to 15 years in Denmark from 1997 to 2010. METHODS Using two national registers, the Danish National Health Service Register and the Danish National Patient Register, practically all cases of middle ear ventilation tube insertion performed in Denmark in the period were identified. A possible change in incidence rate over time was examined using Poisson regression analysis, while the cumulative incidence proportion was estimated using life-tables. RESULTS A total of 502,569 uni- or bilateral ventilation tube insertions distributed among 269,459 different children were identified. From 1997 to 2010 the age standardized incidence rate in 0-15-year-olds increased from 26 to 40 per 1000 person years with an estimated annual increase of 2.0% (95% confidence interval 1.9-2.1%). The largest increase in incidence rate was found in 1-year-olds with an annual increase of 4.5% (95% confidence interval 4.4-4.6%). Age-specific incidence rates remained at maximum around the age of 14 months throughout the period. The cumulative incidence proportion for the 2010 birth cohort by the time they reach the age of 5 years was estimated to 29% (95% confidence interval 28-29%). CONCLUSION The rate for middle ear ventilation tube insertion in Denmark was high compared to other developed countries, and an estimated 3 in 10 children born in 2010 will undergo at least one ventilation tube insertion before their fifth birthday.

Cholesteatoma risk in 8,593 orofacial cleft cases and 6,989 siblings: A nationwide study

To estimate the risk of surgically treated middle ear cholesteatoma in individuals with a nonsyndromic orofacial cleft and in their siblings compared with the general population.

The impact of ventilation tubes in otitis media on the risk of cholesteatoma on a national level

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 VTIs 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.

Cholesteatoma in Danish children – A national study of changes in the incidence rate over 34 years

OBJECTIVE To describe temporal trends in the incidence rate of surgically treated middle ear cholesteatoma in Danish children from 1977 to 2010. METHODS Data on surgically treated middle ear cholesteatoma was drawn from the Danish National Patient Register. A change in incidence rate over time was examined using Poisson regression analysis, while the cumulative incidence proportion was estimated using life-tables. RESULTS A total of 5850 cases of surgically treated middle ear cholesteatoma distributed among 3874 children aged 0-15 years were identified. From 1977 to 2002 the age-standardized incidence rates for first-time surgically treated middle ear cholesteatoma increased from 8 to 15 per 100,000 person-years with an estimated annual increase of 1.8% (95% confidence interval (CI) 1.3-2.2%). From 2002 to 2010 the rates decreased from 15 to 10 per 100,000 person-years with an annual decrease of 5.4% (95% CI 3.2-7.5%). Age-specific incidence rates were at maximum around the age of 9 years during the whole period. The estimated cumulative incidence proportion at age 16 years based on the 2010 age-specific incidence rates was 0.16% (95% CI 0.09-0.32%) compared with 0.20% (95% CI 0.11-0.37%) based on the 2000 age-specific incidence rates. CONCLUSION From 2002 to 2010 there was a decrease in the incidence rate of first-time surgically treated middle ear cholesteatoma. The decrease was preceded by a significant increase in the incidence rate of middle ear ventilation tube insertion. However, further studies are needed to find possible explanations for the decrease.

A nationwide study on the impact of pneumococcal conjugate vaccination on antibiotic use and ventilation tube insertion in Denmark 2000–2014

Introduction of Pneumococcal Conjugated Vaccines (PCV) in national immunization programs have been successful in reducing the number of invasive and lower respiratory pneumococcal infections. The impact of the vaccines on upper respiratory infections caused by pneumococci is less clear although these account for most pneumococcal infections. In this study, we used likely proxies for respiratory infections in children, such as antibiotic use and ventilation tube insertions (VTI), to estimate the impact of the vaccine on a national level. The study was designed as a population-based retrospective observational study, comparing trends in the incidence rate of antibiotic prescriptions and VTIs in the period 2000-2014, where PCV7 was introduced in 2007 and PCV13 in 2010. The introduction of PCV7 and PCV13 correlated with changes in the incidence rate from an almost steady increase in prescription of antibiotics in the pre-PCV period to a decreasing incidence for all children age 0-15years. The 2.4 DDD per person year in 2014 was at almost the same level of antibiotic use as in 2000 at 2.3 DDD per person year. Similar patterns were observed in the mostly vaccinated age groups below 5years of age. For VTI we observed a decreasing incidence rate in the years following introduction of PCV13 ending with a slightly higher incidence at 35 per 1000 person years in 2014 compared to 31 in year 2000. We conclude that the steady increase in antibiotic use and VTI in the pre-PCV period have been partially reversed to near year 2000 levels after the introduction of PCV. This indicates that implementation of pneumococcal vaccines in the Childhood Vaccination Programme has likely reduced the incidence of upper respiratory diseases due to pneumococci in Denmark.

School performance in cholesteatoma-operated children in Denmark: a nationwide population-based register-study

Abstract Conclusion Cholesteatoma in childhood had no long-term effect on school performance for the majority who completed lower secondary school. Aim To investigate whether individuals operated on for cholesteatoma in childhood have impaired school performance in adolescence. Methods All children born in Denmark between 1986–1991 with cholesteatoma surgery performed before the age of 15 years were included (cholestetaoma group). A control group consisting of a 5% random sample of all children born in Denmark during the same period was used for comparison. Final marks (average, mathematics, Danish, and English) achieved upon completion of lower secondary school (9th grade; age 15 or 16 years) were compared between groups. Results A total of 549 individuals met the inclusion criteria for the cholesteatoma group and 15 106 for the control group. High parental education and female sex were strongly associated with high 9th grade marks. The cholesteatoma group did equally as well as the control group in all outcome-measures except from in English (1st foreign language), where children with ≥2 cholesteatoma surgeries scored 0.26 marks lower (95% confidence interval = 0.03–0.48). In the cholesteatoma group, though, the odds ratio for not attaining a 9th grade exam was 1.33 (95% confidence interval = 1.03–1.72%) when compared with the control group.