Predictability of noninvasive liver fibrosis score for cardiac events in patients with nonalcoholic fatty liver disease

Background and aims: Patients with nonalcoholic fatty liver disease (NAFLD) have a higher risk of cardiac events. However, although the severity of liver fibrosis is related to worsening prognosis in patients with NAFLD, it is unclear whether the noninvasive liver fibrosis score has a predictive value for cardiac events. Methods and results: We evaluated 4071 patients with NAFLD diagnosed using ultrasonography. Liver fibrosis was assessed and divided into three groups based on the Fibrosis-4 (FIB4) index and NAFLD fibrosis score (NFS). The primary outcome of this study was major adverse cardiac events (MACE), including cardiac death, nonfatal myocardial infarction, and revascularization due to coronary artery disease. The median age of the evaluated patients was 61 (52-69) years, and 2201 (54.1%) were male. During the median follow-up period of 6.6 years, 179 (4.4%) patients experienced MACE. Kaplan-Meier survival analysis demonstrated that MACE increased progressively with the FIB4 index (log-rank, p < 0.001) and NFS (log-rank, p < 0.001). Multivariable analysis showed that the higher the FIB4 index, the higher the risk for MACE (low group as reference vs. intermediate group, hazard ratio [HR]: 1.860 [95% confidence interval (CI), 1.326-2.610; p < 0.001]; vs. high group, HR:3.325 [95% CI, 2.017-5.479; p < 0.001]), as well as NFS (low NFS group as reference vs. intermediate group, HR: 1.938 [95% CI, 1.391-2.699; p < 0.001]; vs. high group, HR: 3.492 [95% CI, 1.997-6.105; p < 0.001]). Conclusions: The FIB4 index and NFS are associated with the probability of MACE in patients with NAFLD. Clinical trials: The study design was approved by the ethics review board of Ogaki Municipal Hospital (approval number: 20221124-12, registration date: November 28th, 2022). https://www. ogaki-mh.jp/chiken/kenkyu.html.