Fatty liver is an independent predictor of early carotid atherosclerosis

Background & aims: Whether steatosis is incidentally or causally associated with carotid atherosclerosis is debated, and long-term follow-up data are missing. This study aims to examine the impact of steatosis on the presence and progression of carotid intima-media thickness (C-IMT) and carotid plaques (CP) in a large cohort with longitudinal follow-up.

Methods: A retrospective single-center study between 1995 and 2012. Transversal cohort: patients with ⩾2 cardiovascular risk factors without previous cardiovascular events. Longitudinal cohort: patients with two consecutive C-IMT measurements more than 2years apart. Steatosis was defined by a surrogate marker, the fatty liver index (FLI). CP and C-IMT were assessed by carotid ultrasound.

Results: In the transversal cohort (n=5671) both C-IMT and the Framingham risk score (FRS) increased across FLI quartiles (0.58±0.12, 0.61±0.14, 0.63±0.14, 0.64±0.14mm, and 5±5%, 9±7%, 12±8%, 15±9%, p<0.001 for both). Steatosis predicted C-IMT better than diabetes or dyslipidemia. Steatosis independently predicted C-IMT (p=0.002) and FRS (p<0.001) after adjustment for metabolic syndrome and cardiovascular risk factors. In the longitudinal cohort (n=1872, mean follow-up 8±4years), steatosis occurred in 12% and CP in 23% of patients. C-IMT increased in patients with steatosis occurrence (from 0.60±0.13mm to 0.66±0.14mm, p=0.001) whereas it did not change in those that stayed free of steatosis. Steatosis at baseline predicted CP occurrence (OR=1.63, 95% CI 1.10-2.41, p=0.014), independent of age, sex, type-2 diabetes, tobacco use, hsCRP, hypertension and C-IMT.

Conclusions: In patients with metabolic syndrome at risk for cardiovascular events, steatosis contributes to early atherosclerosis and progression thereof, independent of traditional cardiovascular risk factors.