Cancer - Kidney(구연) (E-073) Cumulative Obesity Exposure on the Risk of Kidney Cancer: A Longitudinal Nationwide Cohort Study 가톨릭대학교 서울성모병원 비뇨의학교실, ¹숭실대학교 정보통계보험수리학과, ², 가톨릭대학교 성빈센트병원 허경재, 박용현, 하유신 홍성후, 이지열, 김세웅, 한경도¹, 고승현² Purpose: Obesity is one of the important prognostic factors of kidney cancer. However, little is known regarding the cumulative impacts of obesity on kidney cancer risk. We aimed to analyse the dose- and time-dependent impact of obesity on kidney cancer risk using the Korean National Health Insurance System database. Methods: In total, 3,102,240 participants over 20 years old who received annual health examination more than 4 times consecutively were included in this study. The primary endpoint was newly diagnosed kidney cancer according to the dose- and time-dependent impact of obesity. Dose-dependent impact was measured using body mass index (BMI) and waist circumference (WC), and time-dependent impact was measured using general and abdominal cumulative obesity exposure (gCOE and aCOE). COE was defined as the number of years diagnosed with obesity during the exposure period. Results: We identified 1,831 participants with newly diagnosed kidney cancer (median follow-up: 4.3 years). The hazard ratios (HRs) for kidney cancer increased significantly with increasing BMI and WC. The HRs (95% CI) for kidney cancer increased significantly in the higher gCOE groups (P for trend < 0.001) as follows: 1 (1.33, 95% CI: 1.10–1.60), 2 (1.33, 1.08–1.63), 3 (1.55, 1.30–1.85), and 4 (1.82, 1.64–2.03) years. Similar trends were observed for aCOE (P for trend < 0.001) as follows: 1 (1.42, 1.23–1.64), 2 (1.71, 1.46–2.02), 3 (1.76, 1.48–2.08), and 4 (2.11, 1.84–2.42) years. Risks of kidney cancer related to COE were much more pronounced in participants with the following characteristics: younger than 65 years old, male gender, diabetes, hypertension, and dyslipidaemia. Conclusions: Participants with longer COE was associated with increased risk of kidney cancer in Asian population. Participants with prolonged obesity and metabolic syndrome need to active surveillance for kidney cancer. keywords : Kidney cancer, Cumulative obesity exposure, Obesity duration