Ten-year Trends in the Incidence of Microtia: A Nationwide
Population-based Study from Taiwan
Abstract
Objective: The aim of this study was to analyze the 10-year secular
trends in the incidence of microtia and/or anotia from 2008 to 2017
using nationwide population-based data. Study design: A cross-sectional
study Setting: Taiwan Participants: Patient data were retrieved from
Taiwan’s National Health Insurance Dataset, after identifying 1,152
children aged ≤1 year with a first-time diagnosis of microtia or anotia
between January 2008 and December 2017. The annual microtia-anotia
incidence rate was the sum of new microtia-anotia cases in a year
divided by total infant population in the year. Method: We used the
annual percent change (APC) to study the secular trend in
microtia-anotia incidence rate. Results: The annual incidence rate of
microtia-anotia averaged across the 10-year period was 57.7 per 100,000
infants (standard deviation=8.6). The annual incidence rates of microtia
and anotia were 53.3 and 4.4 per 100,000 infants, respectively, during
this period. Furthermore, female infants had a higher incidence than
males (63.3 vs. 52.4 per 100,000). The incidence of microtia-anotia
gradually decreased between 2008 and 2017 with an APC of -5.64% (95%
CI= -9.31%~-1.18%, p=0.004). Since 2011, females had a
significantly higher annual incidence rate of microtia-anotia than
males. Conclusions: The incidence of microtia-anotia was 57.7 per
100,000 infants in Taiwan, which declined during the study period
2008-2017. The female-to-male incidence ratio was 1.21:1.