Association of ectopic fat with abdominal aorto-illiac and coronary artery calcification in african ancestry men

Atherosclerosis. 2017 Aug:263:198-204. doi: 10.1016/j.atherosclerosis.2017.06.030. Epub 2017 Jun 16.

Abstract

Background and aims: There is strong evidence that fat accumulating in non-adipose sites, "ectopic fat", is associated with cardiovascular disease (CVD), including vascular calcification. Most previous studies of this association have assessed only a single ectopic fat depot. Therefore, our aim was to assess the association of total, regional, and ectopic fat with abdominal aorto-illiac calcification (AAC) and coronary artery calcification (CAC) in 798 African ancestry men.

Methods: Participants (mean age 62) were from the Tobago Bone Health Study cohort. Adiposity was assessed via clinical examination, dual x-ray absorptiometry, and computed tomography (CT). Ectopic fat depots included: abdominal visceral adipose tissue (VAT), liver attenuation, and calf intermuscular adipose tissue (IMAT). Vascular calcification was assessed by CT and quantified as present versus absent. Associations were tested using multiple logistic regression adjusted for traditional cardiovascular risk factors. Models of ectopic fat were additionally adjusted for total body fat and standing height.

Results: All adiposity measures, except VAT, were associated with AAC. Lower liver attenuation or greater calf IMAT was associated with 1.2-1.3-fold increased odds of AAC (p < 0.03 for both), though calf IMAT was a stronger predictor than liver attenuation (p < 0.001) when entered in a single model. No ectopic fat measure was associated with CAC.

Conclusions: Greater adiposity in the skeletal muscle and liver, but not in the visceral compartment, was associated with increased odds of AAC in African ancestry men. These results highlight the potential importance of both quantity and location of adiposity accumulation throughout the body.

Keywords: African ancestry; Computed tomography; Ectopic fat; Vascular calcification.

MeSH terms

  • Absorptiometry, Photon
  • Adiposity / ethnology*
  • Adult
  • Aged
  • Aorta, Abdominal* / diagnostic imaging
  • Aortic Diseases / diagnostic imaging
  • Aortic Diseases / ethnology
  • Aortic Diseases / physiopathology*
  • Aortography / methods
  • Black People*
  • Chi-Square Distribution
  • Computed Tomography Angiography
  • Coronary Angiography / methods
  • Coronary Artery Disease / diagnostic imaging
  • Coronary Artery Disease / ethnology
  • Coronary Artery Disease / physiopathology*
  • Humans
  • Iliac Artery* / diagnostic imaging
  • Intra-Abdominal Fat / diagnostic imaging
  • Intra-Abdominal Fat / physiopathology*
  • Liver / diagnostic imaging
  • Liver / physiopathology*
  • Logistic Models
  • Male
  • Middle Aged
  • Muscle, Skeletal / diagnostic imaging
  • Muscle, Skeletal / physiopathology*
  • Odds Ratio
  • Prospective Studies
  • Risk Factors
  • Trinidad and Tobago / epidemiology
  • Vascular Calcification / diagnostic imaging
  • Vascular Calcification / ethnology
  • Vascular Calcification / physiopathology*