Association between nonalcoholic fatty liver disease and subclinical atherosclerosis: a cross-sectional study on population over 40 years old

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) refers to fatty infiltration of liver in the absence of excessive alcohol abuse. However, the problem that whether NAFLD is correlated with subclinical atherosclerosis assessed by carotid intima-media thickness (CIMT) and brachial-ankle pulse wave velocity (ba-PWV) remains a source of controversy. This can be attributed to the differences in diagnosis methods, population ethnicity, sampling size and bias. This study aimed to further investigate the association of NAFLD with subclinical atherosclerosis. METHODS: A cross-sectional study was carried out in the current study on population aged over 40 years derived from Kailuan community-based prospective study among Chinese adults from June 2010 to June 2011. NAFLD was evaluated through ultrasonography and histories of alcohol consumption. Clinical parameters and medical histories of patients were collected in the manner of interview performed by trained investigators using the standardized questionnaires. The biochemical parameters were analyzed at the central laboratory. CIMT and ba-PWV of each patient were measured. Multivariate logistic regression was used to analyze the associations of NAFLD with subclinical atherosclerosis assessed by CIMT or ba-PWV. RESULTS: A total of 4112 participants aged over 40 years were enrolled from Kailuan cohort, including 2229 men and 1883 women. The overall prevalence of NAFLD was 38.2% in the total population. Statistically significant differences were found in CIMT (P < 0.0001) and ba-PWV (P = 0.0007) according to the presence of NAFLD. It is notably that the multivariate logistic regression revealed NAFLD was independently associated with elevated CIMT after adjusting the conventional cardiovascular and metabolic risk factors (OR = 1.663, 95% CI = 1.391–1.989, P < 0.0001). In addition, NAFLD was also found to be positively associated with elevated ba-PWV after adjusting age, gender, BMI, current smoking and regular exercising (OR = 1.319, 95% CI = 1.072–1.624, P = 0.0089). CONCLUSIONS: Our findings suggest that NAFLD is remarkably correlated with subclinical atherosclerosis, which should be strongly advised to engage in the preventive strategies for cardiovascular diseases (CVDs).