Carotid artery intima-media thickness and endothelial function in patients with nonalcoholic fatty liver disease

ABSTRACT

Nonalcoholic fatty liver disease [NAFLD] is an increasingly recognized cause of liver related morbidity and mortality. Recently, there is increasing evidence of its association with atherosclerotic risk factors and potential cardiovascular risk. The aim of the present study was to evaluate carotid artery intima-media thickness [IMT] and endotheliol function as markers of preclinical atherosclerosis in patients with NAFLD. Methods: The present study included 24 patients with ultrasound diagnosed NAFLD [14 men and 10 women, mean age 47.4 +/- 6.7 years] and 20 age and sex matched control subjects. Patients and control groups were evaluated for metabolic syndrome [Met S] according to Adult Treatment Panel III, insulin resistance index [HOMA-IR], high sensitivity C-reactive protein [Hs-CRP] carotid artery IMT and brachial artery flow mediated dilatation in response to ischemia [FMD] and nitroglycerine induced dilatation [NID]. Visceral obesity, hypertriglyceridemia were more frequent [P=0.03 and 0.01 respectively] with 3 fold increase in the frequency of Met S [33% vs 10%] in NAFLD patients as compared to controls. NAFLD group had increased mean IMT [0.713 +/- 0.181 vs 0.593+0.125, P=0.017], increased plaque frequency [37.5% vs 10%, P=0.03], and lower FMD and NID [5.67 +/- 2.07% us 7.78 +/- 2.42%, P=0.003 and 8.42 +/- 2.71% us 10.31 +/- 2.53%, P=0.022, respectively] as compared to control group. In NAFLD group, IMT correlated significantly with BMI, TG, HOMA-IR [P<0.0001], waist circumference, SBP and Hs-CRP [P=0.002, 0038 and 0.009 respectively], percent FMD correlated significantly with BMI, waist circumference, HOMA-IR, TG and Hs-CRP [P=0.011, 0.003, 0.01, 0.001 and 0.02 respectively]. NAFLD is associated with increased carotid IMF and endothelial dysfunction which are related to the frequent metabolic syndrome features and point to accelerated atherosclerosis. Screening of NAFLD patients with metabolic syndrome features together with the use of non-invasive measures for assessment of preclinical atherosclerosis, could help in early risk assessment and guide for proper life style and therapeutic measures aiming at vascular risk reduction