Eleven-year Cumulative Incidence and Estimated Lifetime Prevalence of Urolithiasis in Korea: a National Health Insurance Service-National Sample Cohort Based Study

BACKGROUND The purpose of this study was estimation of the cumulative incidence and lifetime prevalence of urolithiasis in Korea. METHODS We used a National Health Insurance Service (NHIS) sample cohort dataset that included approximately 1 million individuals from Korea. Data from January 2002 to December 2013 were collected. We calculated the annual prevalence, recurrence rate, and estimate lifetime prevalence of urolithiasis. Multivariate logistic regression analysis was used to identify risk factors associated with urolithiasis. RESULTS There were 57,921 diagnosed urolithiasis cases in the NHIS database over the 11 years studied. The annual incidence of urolithiasis increased every year (Poisson regression; hazard ratio, 1.025; P < 0.001). Of the patients with urolithiasis, 21.3% experienced disease recurrence within 5 years. The 11-year cumulative incidence was 5.71%, and the incidence in men was higher than that seen in women (7.07% vs. 4.34%, respectively). The 11-year cumulative incidence in the 60- to 69-year-old group (9.08%) was higher than that seen in any other age group. The overall standardized lifetime prevalence rate was estimated to be 11.5%: 12.9% in men and 9.8% in women. Meanwhile, age (> 60 years), income level, diabetes, body mass index, hypertension, and cancer history were identified as contributing factors to urolithiasis. CONCLUSION This study demonstrates that the annual incidence of urolithiasis in Korea is increasing. The overall standardized lifetime prevalence rate was higher than that reported in a previous report. This study is significant in that it is the first retrospective cohort study to estimate the lifetime prevalence of urolithiasis using a large national retrospective cohort.