Objective       To determine the effects of abdominal fat accumulation and ectopic liver fat accumulation on arterial stiffness by comparing the cardio-ankle vascular index (CAVI) between the abdominal obese population without nonalcoholic fatty liver disease (NAFLD) (referred to as the abdominal fat accumulation) and the normal weight population with NAFLD (referred to as the ectopic liver fat accumulation).       Methods       A total of 111 552 Chinese Han adults who underwent the health check-ups in our physical examination center from January 2012 to December 2012 were enrolled and screened in this study. Based on their body mass index (BMI)

waist circumference (WC) and presence of NAFLD or not (evaluated by ultrasonography)

these subjects were divided into 3 groups

normal weight control (NW

n=23 599)

abdominal obesity without NAFLD (OB

n=3 238) and normal weight with NAFLD (NAFLD-NW

n=1 161). CAVI (CAVI8 m/s as elevated arterial stiffness) was compared among the 3 groups. Logistic regression analysis was performed to analyze the association of abdominal obesity and NAFLD with CAVI after adjustment for age

sex

blood pressure

serum lipids

blood glucose

liver enzymes and serum creatinine.       Results       The prevalence of NAFLD was 4.69% in population of normal weight and 66.08% in those of abdominal obesity. The NAFLD-NW group had significant higher CAVI than the OB group (8.12±1.16 vs 7.93±1.38

P0.01). When the presence of NAFLD and abdominal obesity were included into regression analysis respectively

either the former or the latter was independently associated with elevated CAVI after adjustment for confounders. Yet when the both indexes were included into regression analysis simultaneously

the association between NAFLD and elevated CAVI remained significant after adjustment for confounders

while that between abdominal obesity and elevated CAVI was no significant. Moreover

the presence of NAFLD conferred greater odds ratios (OR) of having elevated CAVI than the presence of abdominal obesity.       Conclusion       Ectopic liver fat is a greater risk factor than abdominal fat for early atherosclerosis. So

early detection of NAFLD in normal weight population has potential benefits in prevention of atherosclerosis.