Diagnosis of non-alcoholic fatty liver disease (NAFLD) is independently associated with cardiovascular risk in a large austrian screening cohort

Abstract

Background: Many patients with non-alcoholic fatty liver disease (NAFLD) simultaneously suffer from cardiovascular (CV) disease and often carry multiple CV risk factors. Several CV risk factors are known to drive the progression of fibrosis in patients with NAFLD. Objectives: To investigate whether an established CV risk score, the Framingham risk score (FRS), is associated with the diagnosis of NAFLD and the degree of fibrosis in an Austrian screening cohort for colorectal cancer. Material and Methods: In total, 1965 asymptomatic subjects (59 ± 10 years, 52% females, BMI 27.2 ± 4.9 kg/m2) were included in this study. The diagnosis of NAFLD was present if (1) significantly increased echogenicity in relation to the renal parenchyma was present in ultrasound and (2) viral, autoimmune or hereditary liver disease and excess alcohol consumption were excluded. The FRS (ten-year risk of coronary heart disease) and NAFLD Fibrosis Score (NFS) were calculated for all patients. High CV risk was defined as the highest FRS quartile (≥10%). Both univariable and multivariable logistic regression models were used to calculate associations of FRS with NAFLD and NFS. Results: Compared to patients without NAFLD (n = 990), patients with NAFLD (n = 975) were older (60 ± 9 vs. 58 ± 10 years; p < 0.001), had higher BMI (29.6 ± 4.9 vs. 24.9 ± 3.6 kg/m2; p < 0.001) and suffered from metabolic syndrome more frequently (33% vs. 7%; p < 0.001). Cardiovascular risk as assessed by FRS was higher in the NAFLD-group (8.7 ± 6.4 vs. 5.4 ± 5.2%; p < 0.001). A one-percentage-point increase of FRS was independently associated with NAFLD (OR 1.04, 95%CI 1.02-1.07; p < 0.001) after correction for relevant confounders in multivariable logistic regression. In patients with NAFLD, NFS correlated with FRS (r = 0.29; p < 0.001), and FRS was highest in patients with significant fibrosis (F3-4; 11.7 ± 5.4) compared to patients with intermediate results (10.9 ± 6.3) and those in which advanced fibrosis could be ruled-out (F0-2, 7.8 ± 5.9, p < 0.001). A one-point-increase of NFS was an independent predictor of high-risk FRS after correction for sex, age, and concomitant diagnosis of metabolic syndrome (OR 1.30, 95%CI 1.09-1.54; p = 0.003). Conclusion: The presence of NAFLD might independently improve prediction of long-term risk for CV disease and the diagnosis of NAFLD might be a clinically relevant piece in the puzzle of predicting long-term CV outcomes. Due to the significant overlap of advanced NAFLD and high CV risk, aggressive treatment of established CV risk factors could improve prognosis in these patients.