Data Analytic Process of a Nationwide Population-Based Study on Obesity Using the National Health Information Database Presented by the National Health Insurance Service 2006-2015

Background: In Korea, the prevalence of obesity has steadily increased, and the socioeconomic burden of obesity has increased along with it. In 2015, the National Health Insurance Service (NHIS) signed a memorandum of understanding with the Korean Society for the Study of Obesity (KSSO), providing limited open access to its databases so that the status of obesity and obesity management could be investigated. Methods: Using NHIS databases, we analyzed nationwide population-based studies for obesity using the definition of obesity (body mass index ${\geq}25kg/m^2$) in subjects over the age of 20. Age and sex standardization were used for all data. Results: The KSSO released the 'Obesity Fact Sheet 2016' using the 2006-2015 NHIS Health Checkup database. The prevalence of obesity steadily increased from 28.7% in 2006 to 32.4% in 2015, and the prevalence of abdominal obesity also steadily increased from 18.4% in 2009 to 20.8% in 2015. The prevalence of class II obesity steadily increased from 2006 to 2015, such that the total prevalence was 4.8% in 2015 (5.6% in men and 4.0% in women). The highest prevalence of obesity was found in Jeju Island, while the lowest prevalence was found in Daegu City. The highest prevalence of abdominal obesity was also found in Jeju Island, while the lowest prevalence was found in Gwangju City. Conclusion: Based on the Obesity Fact Sheet 2016, a strategy for reducing the prevalence of obesity is needed, especially in Korean men.