Casual Serum Triglyceride Concentrations and New-Onset Chronic Kidney Disease in the General Japanese Population: The Iki City Epidemiological Study of Atherosclerosis and Chronic Kidney Disease Study.

INTRODUCTION: Non-fasting triglyceride (TG) concentrations are useful for predicting various diseases, but most epidemiological studies investigated the association between fasting TG concentrations and chronic kidney disease (CKD). This study aimed to examine the association between casual (fasting or non-fasting) serum TG concentrations and new-onset CKD in the general Japanese population. METHODS: We conducted a population-based, retrospective cohort study using annual health checkup data of residents of Iki City, Nagasaki Prefecture, Japan. Between 2008 and 2019, participants without CKD (estimated glomerular filtration rate <60 mL/min/1.73 m2 and/or proteinuria) at baseline were included. Casual serum TG concentrations were classified by sex as tertile 1 (men: <0.95 mmol/L; women: <0.86 mmol/L), tertile 2 (0.95-1.49 mmol/L; 0.86-1.25 mmol/L), and tertile 3 (≥1.50 mmol/L; ≥1.26 mmol/L). The outcome was incident CKD. Multivariable-adjusted hazard ratios and 95% confidence intervals were estimated using the Cox proportional hazards model. RESULTS: 4,946 participants (2,236 [45%] men and 2,710 [55%] women; 3,666 [74%] fasting and 1,182 [24%] non-fasting) were included in the present analysis. During an average follow-up of 5.2 years, 934 participants (434 men and 509 women) developed CKD. In men, the incidence rate (per 1,000 person-years) of CKD increased with an elevation in TG concentrations (tertile 1: 29.4, tertile 2: 42.2, and tertile 3: 43.3). This association was significant, even after adjustment for other risk factors of age, current smoking habits, current alcohol intake, exercise habits, obesity, hypertension, diabetes mellitus, hyper-low-density-lipoprotein cholesterolemia, and use of lipid-lowering therapy (p = 0.003 for trend). In contrast, in women, TG concentrations were not associated with incident CKD (p = 0.547 for trend). CONCLUSION: Casual serum TG concentrations are significantly associated with new-onset CKD in Japanese men in the general population.