RESUMO
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.
Assuntos
Adiposidade/etnologia , Aorta Abdominal , Doenças da Aorta/fisiopatologia , População Negra , Doença da Artéria Coronariana/fisiopatologia , Artéria Ilíaca , Gordura Intra-Abdominal/fisiopatologia , Fígado/fisiopatologia , Músculo Esquelético/fisiopatologia , Calcificação Vascular/fisiopatologia , Absorciometria de Fóton , Adulto , Idoso , Aorta Abdominal/diagnóstico por imagem , Doenças da Aorta/diagnóstico por imagem , Doenças da Aorta/etnologia , Aortografia/métodos , Distribuição de Qui-Quadrado , Angiografia por Tomografia Computadorizada , Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/etnologia , Humanos , Artéria Ilíaca/diagnóstico por imagem , Gordura Intra-Abdominal/diagnóstico por imagem , Fígado/diagnóstico por imagem , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/diagnóstico por imagem , Razão de Chances , Estudos Prospectivos , Fatores de Risco , Trinidad e Tobago/epidemiologia , Calcificação Vascular/diagnóstico por imagem , Calcificação Vascular/etnologiaRESUMO
SUMMARY: We tested for association between cortical and trabecular volumetric bone mineral density (vBMD) with abdominal aortic calcification (AAC) prevalence in 278 Afro-Caribbean men. AAC was present in 68.3 % of the men. Greater cortical, but not trabecular, vBMD was associated with significantly decreased odds of AAC independent of traditional risk factors. INTRODUCTION: The aim of this study is to assess the prevalence and correlates of AAC in a sample of 278 Afro-Caribbean men (mean age 56) and to test for a largely unexplored association between cortical and trabecular vBMD with AAC prevalence. METHODS: Men were recruited consecutively as part of an ongoing prospective cohort study of body composition in men aged 40+. For this analysis, AAC was assessed by computed tomography of the abdomen from L3 to S1. Aortic calcium was scored using the Agatston method, and prevalence was defined as a score ≥10 to rule out false positives. Men also had BMD assessed using peripheral quantitative computed tomography at 4 % (trabecular vBMD) and 33 % (cortical vBMD) of the radius and tibia. RESULTS: Abdominal aortic calcification was present in 68.3 % of the men. Significant independent predictors of AAC prevalence were increased age, increased BMI, hypertension, and current smoking. Age was the strongest predictor, with each SD (7.8 year) increase in age conferring 2.7 times increased odds of having AAC (P < 0.0001). A one SD greater cortical, but not trabecular, vBMD was associated with a significant decreased odds of AAC prevalence independent of other traditional risk factors (OR 0.65; 95 % CI 0.45-0.92). CONCLUSIONS: Cortical vBMD is inversely associated with AAC presence. This finding suggests that there may be shared physiology between cortical bone compartment remodeling and vascular calcification.