Surrogate scores of advanced fibrosis in NAFLD/NASH do not predict mortality in patients with medium-to-high cardiovascular risk
Background: Untreated NAFLD may have significant consequences including an increase in mortality and cardiovascular injury. Thus, early detection of NAFLD is currently believed not only to prevent liver related but also cardiovascular mortality. However, almost nothing is known about co-existing NAFLD in patients with coronary artery disease (CAD). Aims: We investigated the impact of surrogates scores of fibrosis in NAFLD in a large cohort of patients referred to coronary angiography. Results: Modelling the common NALFD and fibrosis scores FIB-4 and NFS as splines revealed significant associations with all-cause and cardiovascular mortality when Cox regression models were only adjusted for cardiovascular risk factors that were not already included in the calculation of the scores. Stratifying the scores into quartiles yielded hazard ratios (95% CI) for all-cause and cardiovascular mortality for the 4th quartile vs the 1st quartile of 2.28 (1.90-2.75) and 2.11 (1.67-2.67) for FIB-4 and of 3.21 (2.61-3.94) and 3.12 (2.41-4.04) for NFS. However, we did not observe an independent association of FIB-4 or NFS with overall or cardiovascular mortality in our prospective CAD cohort after full adjustment for all cardiovascular risk factors (all-cause mortality HR 1.13 (0.904-1.41) and 1.17 (0.903-1.52); cardiovascular mortality HR 1.06 (0.8-1.41) and 1.02 (0.738-1.41). Thus, neither FIB-4 nor NFS, as surrogate markers for NAFLD/NASH, were independent risk factors for overall or cardiovascular mortality in patients with CAD. Conclusion: Our data shows that surrogate risk scores for NAFLD-related fibrosis do not add information in assessing the CVD events in patients with CAD proven by angiography.