Influences of demographic changes and medical insurance status on tonsillectomy and adenoidectomy rates in Korea

In Korea, the proportion of the pediatric population is decreasing due to low fertility rates and aging of the society. It is hypothesized that this change in population structure and medical insurance status may affect rates of elective surgeries more significantly than clinical factors. An observational study conducted using data from the Health Insurance Review and Assessment Service for tonsillectomy and adenoidectomy, with 403,924 registered patients from 2007 through 2011. We analyzed longitudinal changes in crude and age-adjusted surgery rates of three surgeries—tonsillectomy without adenoidectomy (T), adenoidectomy without tonsillectomy (A), and tonsillectomy with adenoidectomy (T&A)— according to medical insurance status: health insurance (HI) group (better economic status) versus health aid (HA) group (poorer economic status). Most of the sur- geries (51.8 % of T, 93.7 % of A, and 95.1 % of T&A) were performed in patients younger than 15. Over 5 years, the proportion of the child population numbers decreased, from 17.43 to 15.41 % in the HI group and from 21.20 to 13.15 % in the HA group. Thus, crude surgery rates for T, A, and T&A decreased more rapidly in the HA group (7.50, 14.79, and 15.55 %) than the HI group (1.69, 1.49, and 0.90 %) each year. Adjusted sur- gery rates for T, A, and T&A increased in the HI group (1.01, 2.64, and 3.36 %) and decreased in the HA group (1.39, 2.86, and 2.76 %) each year. These adjusted sur- gery rates partially explains the sharper decrease in crude surgery rates in the HA group than the HI group. The crude and adjusted rates of surgeries were usually higher in lower economic status groups. In conclusion, surgery rates were affected by changes in the population structure, but by other factors as well. Predictable socioeconomic factors could be used to calculate and predict the rates for other well-established surgeries.