title: Serum leptin has no effect on coronary collateral development in patients with non-ST-elevation acute coronary syndromes: an observational study.
abstract: OBJECTIVE
  We attempted to investigate the potential association between leptin and coronary collateral vessel development in patients with non-ST elevation acute coronary syndromes (NSTE-ACS).
  
  
  METHODS
  One hundred and nineteen consecutive patients with NSTE-ACS with high-grade coronary stenosis or occlusion in at least one epicardial coronary artery were prospectively enrolled in a cross-sectional observational study. Serum leptin levels measured in all patients. Collateral circulation was graded according to the Rentrop classification. Firstly, we divided patients into two groups as good and poor collateral group. Patients with Rentrop 2.3 were regarded as good collateral group. Patients in Rentrop grades 0, 1 classified as poor collateral group. Secondly, patients were divided into collateral (+) group and collateral (-) group. Collateral (+) group included the patients with grade 1, 2, 3 collateral development. Collateral (-) group was composed of the patients with Rentrop 0. Statistical analysis was performed using Student t-test, Mann-Whitney U test, Chi-square test, Kruskal -Wallis test and Spearman's correlation.
  
  
  RESULTS
  We did not find statistically significant difference between good and poor collateral groups with regard to leptin levels [4.2 (1.8-8.6) ng/mL and 6.4 (2.4-12.6) ng/mL, p=0.22, respectively]. There was no statistically significant difference in leptin levels between collateral (+) group and collateral (-) groups [4.7 (1.7-10.5) ng/mL and 6.8 (2.7-12.1) ng/mL, p=0.33, respectively]. We observed that there was lower leptin level at higher Rentrop grades [Rentrop 0; 6.8 (2.5-12.5) ng/mL, Rentrop 1; 5.9 (1.7-14.1) ng/mL, Rentrop 2; 4.3 (1.7-8.7) ng/mL, Rentrop 3; 3.9 (2.1-9.7) ng/mL]. However, this difference did not reach statistically significant level (p=0.54). In addition, we did not find statistically significant correlation between Rentrop grades and leptin levels (p=0.246, r=-0.107).
  
  
  CONCLUSIONS
  The present study reveals no association between serum leptin level and coronary collateral development.
authors.affiliation: Department of Cardiology, Faculty of Medicine, Erciyes University, Kayseri-Turkey. drgunebakmaz@yahoo.com.
authors.forename: Ozgür
authors.initials: O
authors.lastname: Günebakmaz
authors.forename: Mustafa
authors.initials: M
authors.lastname: Duran
authors.forename: Mahmut
authors.initials: M
authors.lastname: Akpek
authors.forename: Cemil
authors.initials: C
authors.lastname: Zencir
authors.forename: Deniz
authors.initials: D
authors.lastname: Elcik
authors.forename: Abdurrahman
authors.initials: A
authors.lastname: Oğuzhan
authors.forename: Mehmet Güngör
authors.initials: MG
authors.lastname: Kaya
mesh_terms: D054058:Acute Coronary Syndrome / Q000097:blood / Q000503:physiopathology*; D015415:Biomarkers / Q000097:blood*; D003097:Collateral Circulation; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D020738:Leptin / Q000097:blood*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012720:Severity of Illness Index
chemical_list: D015415:Biomarkers; D020738:Leptin