Nonalcoholic fatty liver disease is associated with coronary artery calcification

Abstract

Nonalcoholic fatty liver disease (NAFLD) is related to risk factors of coronary artery disease, such as dyslipidemia, diabetes, and metabolic syndrome, which are closely linked with visceral adiposity. The aim of this study was to investigate whether NAFLD was associated with coronary artery calcification (CAC), which is used as a surrogate marker for coronary atherosclerosis independent of computed tomography (CT)-measured visceral adiposity. Out of 5,648 subjects who visited one of our health screening centers between 2003 and 2008, we enrolled 4,023 subjects (mean age, 56.9 ± 9.4 years; 60.7% males) without known liver disease or a history of ischemic heart disease. CAC score was evaluated using the Agatston method. On univariate analysis, the presence of CAC (score >0) was significantly associated with age, sex, body mass index, aspartate aminotransferase, alanine aminotransferase, high-density lipoprotein cholesterol, triglycerides, and increased risk of diabetes, hypertension, smoking, and NAFLD. Increasing CAC scores (0, <10, 10-100, ≥ 100) were associated with higher prevalence of NAFLD (odds ratio [OR], 1.84; 95% confidence interval [CI], 1.61-2.10; P<0.001). Multivariable ordinal regression analysis was adjusted for traditional risk factors, and CT-measured visceral adipose tissue area in a subgroup of subjects showed that the increased CAC scores were significantly associated with the presence of NAFLD (OR, 1.28, 95% CI, 1.04-1.59; P = 0.023) independent of visceral adiposity.

Conclusion: Patients with NAFLD are at increased risk for coronary atherosclerosis independent of classical coronary risk factors, including visceral adiposity. These data suggest that NAFLD might be an independent risk factor for coronary artery disease.

Fig. 1

Prevalence of nonalcoholic fatty liver disease by coronary artery calcification score cutoff.

Fig. 2

Forest plot shows the ORs of the association between NAFLD and presence of CAC in different subgroups of participants: men versus women, older (age ≥55 years) versus younger (age <55), obese (BMI ≥25) versus nonobese (BMI <25), hypertensive versus nonhypertensive, smokers versus nonsmokers, dyslipidemic (total cholesterol ≥240) versus nondyslipidemic (total cholesterol <240). ORs are represented by black circles; 95% CIs are denoted by horizontal whiskers.

Fig. 3

Visceral adipose tissue area and subcutaneous adipose tissue area between coronary artery calcification score cutoff. (A) As coronary artery calcification score increases, visceral adipose tissue area increases dose-dependently. (B) Associations between CAC score and subcutaneous adipose area were not statistically significant. The horizontal line in each box represents the median. The top and bottom of each box represent the 25th and 75th percentiles (interquartile range).

Fig. 3

Visceral adipose tissue area and subcutaneous adipose tissue area between coronary artery calcification score cutoff. (A) As coronary artery calcification score increases, visceral adipose tissue area increases dose-dependently. (B) Associations between CAC score and subcutaneous adipose area were not statistically significant. The horizontal line in each box represents the median. The top and bottom of each box represent the 25th and 75th percentiles (interquartile range).