Date Published: April 23, 2019
Publisher: Public Library of Science
Author(s): Darren W. Westphal, Deborah Lehmann, Stephanie A. Williams, Peter C. Richmond, Francis J. Lannigan, Parveen Fathima, Christopher C. Blyth, Hannah C. Moore, Shinya Tsuzuki.
Otitis media (OM) is one of the most common infectious diseases affecting children globally and the most common reason for antibiotic prescription and paediatric surgery. Australian Aboriginal children have higher rates of OM than non-Aboriginal children; however, there are no data comparing OM hospitalization rates between them at the population level. We report temporal trends for OM hospitalizations and in-hospital tympanostomy tube insertion (TTI) in a cohort of 469,589 Western Australian children born between 1996 and 2012.
We used the International Classification of Diseases codes version 10 to identify hospitalizations for OM or TTI recorded as a surgical procedure. Using age-specific population denominators, we calculated hospitalization rates per 1,000 child-years by age, year and level of socio-economic deprivation.
There were 534,674 hospitalizations among 221,588 children hospitalized at least once before age 15 years. Aboriginal children had higher hospitalization rates for OM than non-Aboriginal children (23.3/1,000 [95% Confidence Interval (CI) 22.8,24.0] vs 2.4/1,000 [95% CI 2.3,2.4] child-years) with no change in disparity over time. Conversely non-Aboriginal children had higher rates of TTI than Aboriginal children (13.5 [95% CI 13.2,13.8] vs 10.1 [95% CI 8.9,11.4]). Children from lower socio-economic backgrounds had higher OM hospitalization rates than those from higher socio-economic backgrounds, although for Aboriginal children hospitalization rates were not statistically different across all levels of socio-economic disadvantage. Hospitalizations for TTI among non-Aboriginal children were more common among those from higher socio-economic backgrounds. This was also true for Aboriginal children; however, the difference was not statistically significant. There was a decline in OM hospitalization rates between 1998 and 2005 and remained stable thereafter.
Aboriginal children and children from lower socio-economic backgrounds were over-represented with OM-related hospitalizations but had fewer TTIs. Despite a decrease in OM and TTI hospitalization rates during the first half of the study for all groups, the disparity between Aboriginal and non-Aboriginal children and between those of differing socioeconomic deprivation remained.
Otitis media (OM) is one of the most common infectious diseases affecting children . Approximately two-thirds of Australian children will have at least one episode of OM by the time they reach their first birthday . Incidence is most common among children aged 18–24 months . OM is the most common reason for antibiotic prescription, thus contributing to increased antibiotic resistance in the common bacterial pathogens responsible for OM . OM also leads to the most commonly performed surgery in children, namely tympanostomy tube insertion (TTI), as well as adenoidectomy or adenotonsillectomy . TTI is recommended for management of recurrent acute OM (AOM) or persistent bilateral OM with effusion (OME) with hearing loss.
There were 31,348 (6.7%) Aboriginal children and 240,237 (51.2%) boys from the overall cohort of 469,859 births between 1996 and 2012. Singleton births accounted for 455,675 (97.0%) of the cohort and 2,538 (0.5%) children had died by the end of the study period. There were 534,674 hospitalization episodes recorded for 221,588 children hospitalized at least once before the age of 15 years. There were 70,665 (13.2%) hospitalizations for Aboriginal children. OM (excluding procedures) accounted for 7,258 (1.6%) of all hospitalizations among non-Aboriginal and 5,210 (7.4%) among Aboriginal children (Fig 1). Among these, OM hospitalizations were coded as the principal diagnosis in 2,437/7,258 (33.6%) of non-Aboriginal and 1,292/5,210 (24.8%) of Aboriginal children. In S1 Table we list the primary diagnoses when only an additional diagnosis field had an OM code.
To our knowledge, this is the first report of hospitalization rates for OM in a total birth cohort that has examined differences between Aboriginal and non-Aboriginal children and between levels of socio-economic disadvantage. Throughout the study period Aboriginal children were 10 times more likely to be hospitalized for OM than non-Aboriginal children but less likely to have TTI. The disparity remained even when only principal diagnoses were compared (S1 Fig). Furthermore, while hospitalization rates were consistently higher in Aboriginal than non-Aboriginal children, non-Aboriginal children from low socio-economic backgrounds and all children living in rural or remote areas were at increased risk of hospitalization for OM but less likely to have TTI.
All Aboriginal children and those non-Aboriginal children from lower socio-economic backgrounds were over-represented with OM-related hospitalizations but had fewer TTIs. Future work to reduce the burden of OM among these children should focus on the social determinants of health, particularly the reduction of poverty and increased availability of services especially in rural and remote areas. Data linkage is a robust way to measure rates, and this gives us reason to better understand the differences in hospitalizations between groups of children.