Evaluation of circulating adipokines and abdominal obesity as predictors of significant myocardial ischemia using gated single-photon emission computed tomography.
OBJECTIVE
Coronary artery disease (CAD) is associated with abdominal obesity and metabolic syndrome. Adipocytes secrete adipokines, including the newly discovered adipocyte fatty acid binding protein (A-FABP) and chemerin. Adipokines contribute to the pathogenesis of CAD. In patients with CAD, the presence of significant ischemia predicts adverse outcomes. It is unknown whether adipokines can be better predictors of the presence of significant myocardial ischemia than conventional risk factors. This study aimed to compare adipokines with clinical risk factors and abdominal obesity as predictive factors for significant myocardial ischemia.


METHODS
One hundred and ninety-six adults with suspected, but unproven, CAD were consecutively enrolled. The main measures were clinical and biochemical parameters and stress myocardial perfusion imaging with gated myocardial perfusion single-photon emission computed tomography (SPECT), with computed tomography (CT) attenuation correction. The abdominal visceral fat area was examined using a hybrid SPECT/CT scanner. Serum levels of high-sensitivity C-reactive protein (hs-CRP) and adipokines (adiponectin, A-FABP, and chemerin) were evaluated.


RESULTS
A-FABP levels correlated significantly with adiponectin, hs-CRP, body mass index, waist circumference, and visceral fat area. A-FABP was significantly associated with metabolic syndrome (OR 3.2, 95% CI 1.6-6.4, p = 0.001), significant myocardial ischemia (OR 1.9, 95% CI 1.0-3.4, p = 0.05), and stress lung-to-heart ratio (β = 0.03, p = 0.03) on SPECT. Chemerin was significantly associated with serum triglyceride levels but not with metabolic syndrome, significant ischemia, or stress lung-to-heart ratio on SPECT. A-FABP was better at detecting significant inducible ischemia than other biomarkers, although this was a modest improvement (area under ROC curve 0.579, 95% CI 0.46-0.69).


CONCLUSIONS
Serum A-FABP concentrations correlate significantly with visceral fat area, metabolic syndrome, and predicted significant myocardial ischemia on SPECT. This may help to more accurately assess CAD risk, especially in patients with metabolic syndrome.
Department of Internal Medicine (Cardiology Division), National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan.
Chi-Sheng
CS
Hung
Department of Internal Medicine (Cardiology Division), National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan; Department of Nuclear Medicine, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan; Cardiology Division of Cardiovascular Medical Center and Department of Nuclear Medicine, Far Eastern Memorial Hospital, New Taipei City, Taiwan; National Yang-Ming University School of Medicine, Taipei, Taiwan.
Yen-Wen
YW
Wu
Department of Nuclear Medicine, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan.
Jei-Yie
JY
Huang
Department of Nuclear Medicine, National Taiwan University Hospital, Yun-Lin Branch, Douliou City, Taiwan.
Pei-Ying
PY
Hsu
Department of Internal Medicine (Cardiology Division), National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan.
Ming-Fong
MF
Chen
D054392:Adipokines / Q000097:blood*; D052242:Adiponectin / Q000097:blood; D019540:Area Under Curve; D015992:Body Mass Index; D050556:Fatty Acid-Binding Proteins / Q000097:blood; D006801:Humans; D017202:Myocardial Ischemia / Q000097:blood / Q000175:diagnosis* / Q000209:etiology; D056128:Obesity, Abdominal / Q000150:complications / Q000473:pathology*; D016017:Odds Ratio; D012372:ROC Curve; D012307:Risk Factors; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods; D055105:Waist Circumference
D054392:Adipokines; D052242:Adiponectin; C493410:FABP4 protein, human; D050556:Fatty Acid-Binding Proteins