Decreasing incidence rate for surgically treated middle ear cholesteatoma in Denmark 1977-2007.
BACKGROUND
The objective was to estimate the annual incidence rate of surgically treated middle ear cholesteatoma (STMEC) in Denmark from 1977 to 2007, taking age, gender and secular trends into consideration.


METHODS
We used the Danish National Hospital Register to identify all registered cases of STMEC in Denmark between 1977 and 2007. Only the first registration of STEMC (STEMC1) was used for estimation of the annual incidence rate.


RESULTS
A total of 13,606 cases of STMEC1 were identified. The highest incidence rates were seen in the beginning of the eighties with a maximum male incidence rate of 14.3 per 100,000 person-years in 1982 and a maximum female incidence rate of 9.1 per 100,000 person-years in 1981. In 2007 the incidence rate per 100,000 person-years was 8.5 for males and 5.4 for females. The age-specific incidence rate peaked at approx. nine years for both males and females with incidence rates of 21.4 and 13.6 per 100,000 person-years, respectively. The male:female incidence rate ratio was 1.51.


CONCLUSIONS
The incidence rate of STMEC1 in Denmark showed a statistically significant decrease from 1977 to 2007. A male predominance was found. The age-specific incidence rate peaked at the age of approx. nine years. Further studies are required to perform a detailed analysis of factors that may influence the incidence rate of STMEC1, e.g. the incidence of grommet insertion and adenoidectomy, antibiotic treatment of middle ear infections and an expanding use of otomicroscopy in the early 1980s.
Department of ENT Head and Neck Surgery, Odense University Hospital, 5000 Odense C, Denmark. bjarki_d@hotmail.com
Bjarki Ditlev
BD
Djurhuus
Christian Emil
CE
Faber
Axel
A
Skytthe
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D018424:Cholesteatoma, Middle Ear / Q000175:diagnosis* / Q000453:epidemiology / Q000601:surgery; D016001:Confidence Intervals; D003718:Denmark / Q000453:epidemiology; D005260:Female; D006801:Humans; D015994:Incidence; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D010045:Outpatients; D012307:Risk Factors; D012737:Sex Factors; D055815:Young Adult