title: Insulin resistance, subclinical left ventricular remodeling, and the obesity paradox: MESA (Multi-Ethnic Study of Atherosclerosis).
abstract: OBJECTIVE
  This study assessed whether impaired fasting glucose (IFG), insulin resistance, and waist-to-hip ratio (WHR) had effects on cardiac remodeling, independent of obesity, in the MESA (Multi-Ethnic Study of Atherosclerosis) trial.
  
  
  BACKGROUND
  Recent studies have suggested that central obesity and insulin resistance may be primary mediators of obesity-related cardiac remodeling independent of body mass index (BMI).
  
  
  METHODS
  We investigated 4,364 subjects without diabetes in the MESA trial. IFG (100 to 125 mg/dl) or insulin resistance (by homeostatic model assessment of insulin resistance [HOMA-IR]) and WHR were used for cardiometabolic phenotyping. Multivariate linear regression analysis was used to determine the effects of the cardiometabolic markers on left ventricular (LV) remodeling, assessed primarily through the LV mass-to-volume ratio obtained by cine cardiac magnetic resonance imaging.
  
  
  RESULTS
  Individuals with IFG were more likely to be older and hypertensive, with increased prevalence of cardiometabolic risk factors regardless of BMI. In each quartile of BMI, subjects with above-median HOMA-IR, above-median WHR, or IFG had a higher LV mass-to-volume ratio (p < 0.05 for all). HOMA-IR (p < 0.0001), WHR (p < 0.0001), and the presence of IFG (p = 0.04), but not BMI (p = 0.24), were independently associated with LV mass-to-volume ratio after adjustment for age, sex, hypertension, race, and dyslipidemia.
  
  
  CONCLUSIONS
  Insulin resistance and WHR were associated with concentric LV remodeling independent of BMI. These results support the emerging hypothesis that the cardiometabolic phenotype, defined by insulin resistance and central obesity, may play a critical role in LV remodeling independently of BMI.
authors.affiliation: Non-Invasive Cardiovascular Imaging Laboratory, Brigham and Women's Hospital, Boston, Massachusetts, USA.
authors.forename: Ravi V
authors.initials: RV
authors.lastname: Shah
authors.forename: Siddique A
authors.initials: SA
authors.lastname: Abbasi
authors.forename: Bobak
authors.initials: B
authors.lastname: Heydari
authors.forename: Carsten
authors.initials: C
authors.lastname: Rickers
authors.forename: David R
authors.initials: DR
authors.lastname: Jacobs
authors.forename: Lu
authors.initials: L
authors.lastname: Wang
authors.forename: Raymond Y
authors.initials: RY
authors.lastname: Kwong
authors.forename: David A
authors.initials: DA
authors.lastname: Bluemke
authors.forename: Joao A C
authors.initials: JA
authors.lastname: Lima
authors.forename: Michael
authors.initials: M
authors.lastname: Jerosch-Herold
mesh_terms: D000368:Aged; D050197:Atherosclerosis / Q000150:complications* / Q000208:ethnology / Q000503:physiopathology; D001786:Blood Glucose; D005006:Ethnicity; D005260:Female; D006352:Heart Ventricles / Q000503:physiopathology*; D006801:Humans; D007333:Insulin Resistance / Q000208:ethnology* / Q000502:physiology; D019028:Magnetic Resonance Imaging, Cine; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000150:complications* / Q000208:ethnology; D012307:Risk Factors; D020257:Ventricular Remodeling / Q000502:physiology*; D049629:Waist-Hip Ratio
chemical_list: D001786:Blood Glucose