Non-alcoholic fatty liver disease and subclinical atherosclerosis: A comparison of metabolically- versus genetically-driven excess fat hepatic storage

Atherosclerosis. 2017 Feb:257:232-239. doi: 10.1016/j.atherosclerosis.2016.12.018. Epub 2016 Dec 21.

Abstract

Background and aims: Non-alcoholic fatty liver disease (NAFLD) is frequently associated with atherosclerosis. However, it is unclear whether this association is related to excess fat liver storage per se or to metabolic abnormalities that typically accompany NAFLD. To investigate this, we compared individuals with hepatic steatosis driven by metabolic disturbances to those with hepatic steatosis associated with the rs738409 GG genotype in the patatin-like phospholipase domain-containing 3 gene (PNPLA3).

Methods: Carotid intima-media thickness (CIMT), as a surrogate marker of subclinical atherosclerosis, was measured in 83 blood donors with the mutant GG genotype (group G), 100 patients with features of metabolic syndrome (MetS) but the wildtype CC genotype (group M), and 74 blood donors with the wildtype CC genotype (controls). Fatty liver was evaluated by ultrasonography and hepatic fat fraction (HFF) was measured using magnetic resonance (MRS/MRI) in 157 subjects.

Results: Compared with group G and controls, group M subjects were older and had increased adiposity indices, dyslipidemia, insulin resistance and elevated transaminase levels (all p < 0.05). They also had a more fatty liver on both ultrasonography and MRS/MRI. After adjustment for confounders (including severity of hepatic steatosis), the median CIMT in group M (0.84 [0.70-0.95] mm) was significantly greater than that in group G (0.66 [0.55-0.74] mm; p < 0.001), which was similar to that in controls (0.70 [0.64-0.81] mm). Results were similar in the subgroup evaluated using MRS/MRI.

Conclusions: Excess liver fat accumulation appeared to increase the burden of subclinical atherosclerosis only when it is associated with metabolic abnormalities.

Keywords: Atherosclerosis; Carotid intima-media thickness; Ectopic fat storage; Non-alcoholic fatty liver disease; PNPLA3.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Asymptomatic Diseases
  • Carotid Artery Diseases / diagnostic imaging
  • Carotid Artery Diseases / etiology*
  • Carotid Artery, Common / diagnostic imaging
  • Carotid Intima-Media Thickness
  • Female
  • Genetic Predisposition to Disease
  • Genetic Variation*
  • Humans
  • Lipase / genetics*
  • Lipid Metabolism*
  • Liver / diagnostic imaging
  • Liver / metabolism*
  • Magnetic Resonance Imaging
  • Magnetic Resonance Spectroscopy
  • Male
  • Membrane Proteins / genetics*
  • Middle Aged
  • Non-alcoholic Fatty Liver Disease / diagnosis
  • Non-alcoholic Fatty Liver Disease / genetics*
  • Non-alcoholic Fatty Liver Disease / metabolism*
  • Phenotype
  • Predictive Value of Tests
  • Risk Assessment
  • Risk Factors
  • Ultrasonography

Substances

  • Membrane Proteins
  • Lipase
  • adiponutrin, human