title: Association of admission serum calcium levels and in-hospital mortality in patients with acute ST-elevated myocardial infarction: an eight-year, single-center study in China.
abstract: OBJECTIVE
  The relationship between admission serum calcium levels and in-hospital mortality in patients with acute ST-segment elevation myocardial infarction (STEMI) has not been well definitively explored. The objective was to assess the predictive value of serum calcium levels on in-hospital mortality in STEMI patients.
  
  
  METHODS
  From 2003 to 2010, 1431 consecutive STEMI patients admitted to the First Affiliated Hospital of Nanjing Medical University were enrolled in the present study. Patients were stratified according to quartiles of serum calcium from the blood samples collected in the emergency room after admission. Between the aforementioned groups,the baseline characteristics, in-hospital management, and in-hospital mortality were analyzed. The association of serum calcium level with in-hospital mortality was calculated by a multivariable Cox regression analysis.
  
  
  RESULTS
  Among 1431 included patients, 79% were male and the median age was 65 years (range, 55-74). Patients in the lower quartiles of serum calcium, as compared to the upper quartiles of serum calcium, were older, had more cardiovascular risk factors, lower rate of emergency revascularization,and higher in-hospital mortality. According to univariate Cox proportional analysis, patients with lower serum calcium level (hazard ratio 0.267, 95% confidence interval 0.164-0.433, p<0.001) was associated with higher in-hospital mortality. The result of multivariable Cox proportional hazard regression analyses showed that the Killip's class≥3 (HR = 2.192, p = 0.026), aspartate aminotransferase (HR = 1.001, p<0.001), neutrophil count (HR = 1.123, p<0.001), serum calcium level (HR = 0.255, p = 0.001), and emergency revascularization (HR = 0.122, p<0.001) were significantly and independently associated with in-hospital mortality in STEMI patients.
  
  
  CONCLUSIONS
  Serum calcium was an independent predictor for in-hospital mortality in patients with STEMI. This widely available serum biochemical index may be incorporated into the current established risk stratification model of STEMI patients. Further studies are required to determine the actual mechanism and whether patients with hypocalcaemia could benefit from calcium supplement.
authors.affiliation: Department of Cardiology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Lu
authors.affiliation: Department of Cardiology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
authors.forename: Yunle
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Cardiology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
authors.forename: Haoyu
authors.initials: H
authors.lastname: Meng
authors.affiliation: Department of Cardiology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
authors.forename: Pengsheng
authors.initials: P
authors.lastname: Chen
authors.affiliation: Department of Gastroenterology, the Drum Tower Hospital of Nanjing Medical University, Nanjing, China.
authors.forename: Yaqing
authors.initials: Y
authors.lastname: Huang
authors.affiliation: Department of Cardiology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
authors.forename: Zemu
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Department of Cardiology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
authors.forename: Ningtian
authors.initials: N
authors.lastname: Zhou
authors.affiliation: Department of Cardiology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
authors.forename: Chunjian
authors.initials: C
authors.lastname: Li
authors.affiliation: Department of Cardiology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
authors.forename: Liansheng
authors.initials: L
authors.lastname: Wang
authors.affiliation: Department of Cardiology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
authors.forename: Enzhi
authors.initials: E
authors.lastname: Jia
authors.affiliation: Department of Cardiology, the First Affiliated Hospital of Nanjing Medical University, Nanjing, China; Department of Geriatrics, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
authors.forename: Zhijian
authors.initials: Z
authors.lastname: Yang
mesh_terms: D000368:Aged; D002118:Calcium / Q000097:blood*; D002318:Cardiovascular Diseases / Q000097:blood / Q000401:mortality; D002681:China; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000097:blood* / Q000401:mortality*
chemical_list: D002118:Calcium