Potential link between high FIB-4 score and chronic kidney disease in metabolically healthy men

Although the association between non-alcoholic fatty liver disease and chronic kidney disease (CKD) has been well known, it is unclear whether Fibrosis-4 (FIB-4) score is a predictor of CKD development. We performed this retrospective cohort study, with a longitudinal analysis of 5-year follow-up data from Japanese annual health check-ups. Participants with CKD (estimated glomerular filtration rate [eGFR] < 60 mL/min/1.73 m(2) and/or proteinuria) and a habit of alcohol consumption were excluded. The cut-off FIB-4 score was 1.30, indicating increased risk of liver fibrosis. Overall, 5353 participants (men only) were analyzed without exclusion criteria. After propensity score matching, high FIB-4 score (≥ 1.30) was not an independent risk factor for incident CKD (odds ratio [OR] 1.57; 95% confidence interval [CI] 0.97–2.56). However, high FIB-4 score was a significant risk factor for CKD in non-obese (OR 1.92; 95% CI 1.09–3.40), non-hypertensive (OR 2.15; 95% CI 1.16–3.95), or non-smoking (OR 1.88; 95% CI 1.09–3.23) participants. In these participants, FIB-4 score was strongly associated with eGFR decline in the multiple linear regression analysis (β = − 2.8950, P = 0.011). Therefore, a high FIB-4 score may be significantly associated with CKD incidence after 5 years in metabolically healthy participants.