Correlation of serum apelin level with coronary calcium score in patients with suspected coronary artery disease

摘要

IntroductionA growing body of evidence indicates that apelin, a relatively recent member of the adipokines family, has a potential anti-atherogenic effect. An association between low serum apelin state and coronary artery disease (CAD) was previously reported; however, the relationship between apelin and the atherosclerotic burden was unclear.ObjectivesOur aim was to explore the correlation of serum apelin level with coronary calcium score (CCS) as a quantitative marker of coronary atherosclerosis.MethodsThis observational cross-sectional study enrolled 100 consecutive subjects referred for cardiac multi-detector computed tomography (MDCT) for assessment of CAD (mean age 54±9.7 years, 51 male and 49 females). Clinical parameters, glycemic and lipid profile, high sensitivity CRP (hsCRP), homeostasis model assessment of insulin resistance (HOMA-IR), serum creatinine and complete blood count were assessed. Serum apelin levels were determined using a commercially available Enzyme Immunoassay (EIA) Kit. High resolution non contrast CT images were acquired by a 64-raw MDCT and CCS was calculated using the Agatston scoring method.ResultsForty three percent of the studied subjects had positive coronary artery calcification (CAC). The mean CCS was 79±196.5 Agatston units. Subjects with detectable CAC had significantly higher fasting plasma glucose, HbA1c and WBCs count than subjects without detectable CAC (p<0.05). Most importantly, subjects with detectable CAC had significantly lower serum apelin level than subjects without CAC (1.3±0.4ng/ml vs. 2.8±0.6ng/ml,p<0.001). In addition, there was a statistically significant inverse correlation between serum apelin levels and CCS (r=0.591,p<0.001); on multivariate analysis this correlation was found to be independent of traditional cardiovascular risk factors and hs-CRP.ConclusionTo the best of our knowledge, this is the first report of an independent association between apelin and CCS in patients with suspected CAD. Apelin emerges as a possible novel biomarker for CAD, but this result remains to be proved prospectively.