title: Relationship of interleukin-6 with regional and global left-ventricular function in asymptomatic individuals without clinical cardiovascular disease: insights from the Multi-Ethnic Study of Atherosclerosis.
abstract: OBJECTIVE
  We sought to examine the relationship between circulating interleukin-6 (IL-6) level and regional left-ventricular (LV) function among apparently healthy individuals free of cardiovascular disease.
  
  
  RESULTS
  Using magnetic resonance myocardial tagging, we determined peak systolic circumferential strain (Ecc) as a measure of regional systolic function in 894 asymptomatic participants in the Multi-Ethnic Study of Atherosclerosis. Ecc was analysed by harmonic phase imaging separately in the LV anterior wall, septum, lateral wall, and inferior wall. Global Ecc was calculated as the average of Ecc in all myocardial segments. We performed multivariable linear regression to evaluate the independent associations between log IL-6 and Ecc, after adjusting for demographic features, cardiovascular risk factors, and markers of subclinical atherosclerosis. The inverse relationships between IL-6 and absolute Ecc were similar in both genders. In multivariable analysis, higher IL-6 level was independently associated with reduced systolic function (less negative Ecc) in the septum [regression coefficient = 1.03 per unit higher log IL-6, 95% confidence interval (CI) 0.26-1.79, P = 0.008] and inferior wall (regression coefficient = 1.65, 95% CI 0.74-2.56, P < 0.001), but not in the anterior wall (P = 0.27) or lateral wall (P = 0.52). Overall, there was an independent inverse association between IL-6 and global Ecc (regression coefficient = 0.94, 95% CI 0.37-1.51, P = 0.001). Compared with C-reactive protein, higher IL-6 level demonstrates a stronger independent association with reduced regional systolic function.
  
  
  CONCLUSIONS
  In asymptomatic men and women without documented cardiovascular disease, there is a strong, independent, inverse relationship between IL-6 and regional LV systolic function. These findings suggest that IL-6 may underlie the pathogenetic link between inflammation, LV dysfunction and incipient heart failure. The observed variable relationships between IL-6 and systolic function across different LV regions warrant further investigations.
authors.affiliation: Division of Cardiology, St. Michael's Hospital, University of Toronto, Toronto, ON, Canada.
authors.forename: Andrew T
authors.initials: AT
authors.lastname: Yan
authors.forename: Raymond T
authors.initials: RT
authors.lastname: Yan
authors.forename: Mary
authors.initials: M
authors.lastname: Cushman
authors.forename: Alban
authors.initials: A
authors.lastname: Redheuil
authors.forename: Russell P
authors.initials: RP
authors.lastname: Tracy
authors.forename: Donna K
authors.initials: DK
authors.lastname: Arnett
authors.forename: Boaz D
authors.initials: BD
authors.lastname: Rosen
authors.forename: Robyn L
authors.initials: RL
authors.lastname: McClelland
authors.forename: David A
authors.initials: DA
authors.lastname: Bluemke
authors.forename: Joao A C
authors.initials: JA
authors.lastname: Lima
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D050197:Atherosclerosis / Q000175:diagnosis* / Q000503:physiopathology; D015415:Biomarkers / Q000378:metabolism; D002097:C-Reactive Protein / Q000378:metabolism; D005260:Female; D006333:Heart Failure / Q000175:diagnosis*; D006801:Humans; D015850:Interleukin-6 / Q000378:metabolism*; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012044:Regression Analysis; D012307:Risk Factors; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis* / Q000378:metabolism; D016277:Ventricular Function, Left / Q000502:physiology
chemical_list: D015415:Biomarkers; D015850:Interleukin-6; D002097:C-Reactive Protein