Non-alcoholic fatty liver disease presence and severity are associated with aortic stiffness beyond abdominal obesity: The ELSA-Brasil

Background and aims: It is uncertain whether non-alcoholic fatty liver disease (NAFLD) is associated with aortic stiffness in a racial/ethnically diverse and admixed society. We addressed whether NAFLD presence and severity were associated with carotid-femoral pulse wave velocity (cf-PWV) in individuals free of cardiovascular disease. Methods: In 7196 individuals free of cardiovascular disease at the baseline Brazilian longitudinal study of adult health, we classified NAFLD presence and severity (mild, moderate and severe) by ultrasound hepatic attenuation. We measured cf-PWV using a non-invasive validated device (Complior SP, Artech Medicale France). We compared cf-PWV of NAFLD individuals to those without by analysis of covariance adjusted for demographics, life style, waist circumference, and arterial pressure. We also analyzed the cf-PWV trend from no-NAFLD to severe NAFLD. Results: In unadjusted analysis, from no-NAFLD to severe NAFLD, there were slightly older individuals, lower frequency of smokers, more prevalent diabetes and hypertension. In adjusted analysis, there was slightly higher cf-PWV (m/s) (95% CI) in NAFLD vs. no-NAFLD, respectively 9.32 (9.22, 9.41) and 9.24 (9.15, 9.33) (p= 0.037). Across NAFLD severity spectrum, adjusted cf-PWV increased from 9.24 (9.15, 9.33) in no-NAFLD to 9.69 (9.46, 9.93) in severe NAFLD (p for trend association= 0.001). In sensitivity analysis, diabetes adjustment nullified the association of binary NAFLD with cf-PWV, but not that of increasingly severe NAFLD. Conclusions: In racial/ethnically diverse individuals free of cardiovascular disease, NAFLD is associated with aortic stiffness beyond abdominal obesity. The specific NAFLD impact on CVD worldwide is potentially relevant.