title: A metabolically healthy obese phenotype in hispanic participants in the IRAS family study.
abstract: OBJECTIVE
  Some obese individuals appear to be protected from developing type 2 diabetes mellitus and cardiovascular disease (CVD). This has led to characterizing body size phenotypes based on cardiometabolic risk factors specifically as obese or overweight, and as metabolically healthy (MH) or metabolically abnormal (MA) based upon blood pressure, lipids, glucose homeostasis, and inflammatory parameters. The aim of this study was to measure the prevalence of and describe fat distribution across these phenotypes in a minority population.
  
  
  METHODS
  Hispanic participants (N = 1054) in the IRAS Family Study were categorized into different body size phenotypes. Computed tomography (CT) abdominal scans were evaluated for measures of nonalcoholic fatty liver disease (NAFLD) and abdominal fat distribution. Statistical models adjusting for familial relationships were estimated.
  
  
  RESULTS
  Seventy percent (70%) of the Hispanic cohort was overweight (32%) or obese (38%). Forty-one percent (n = 138) of overweight participants and 19% (n = 74) of obese participants met criteria for MH. Adjusted analyses showed the MH phenotype was associated with lower visceral adipose tissue (VAT) and higher liver density (indicating lower fat content) in obese participants (p = 0.0005 and p = 0.0002, respectively), and lower VAT but not liver density in overweight participants (p = 0.008 and p = 0.162, respectively) compared to their MA counterparts. Odds of NAFLD were reduced in MH obese (OR = 0.34, p = 0.0007) compared to MA obese. VAT did not differ between MH obese or overweight and normal weight groups.
  
  
  CONCLUSIONS
  These findings suggest that lower levels of visceral and liver fat, despite overall increased total body fat, may be a defining feature of MH obesity in Hispanic Americans.
authors: Department of Medicine, Section of Endocrinology and Metabolism, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA.
authors: Xanthia F
authors: XF
authors: Samaropoulos
authors: Kristen G
authors: KG
authors: Hairston
authors: Andrea
authors: A
authors: Anderson
authors: Steven M
authors: SM
authors: Haffner
authors: Carlos
authors: C
authors: Lorenzo
authors: Maria
authors: M
authors: Montez
authors: Jill M
authors: JM
authors: Norris
authors: Ann L
authors: AL
authors: Scherzinger
authors: Yii-Der Ida
authors: YD
authors: Chen
authors: Lynne E
authors: LE
authors: Wagenknecht
mesh_terms: D050153:Abdominal Fat / Q000000981:diagnostic imaging / Q000473:pathology; D000328:Adult; D050218:Body Fat Distribution; D002318:Cardiovascular Diseases / Q000453:epidemiology; D015331:Cohort Studies; D005260:Female; D006262:Health; D006630:Hispanic or Latino / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D008875:Middle Aged; D065626:Non-alcoholic Fatty Liver Disease / Q000453:epidemiology; D009765:Obesity / Q000000981:diagnostic imaging / Q000208:ethnology* / Q000378:metabolism*; D050177:Overweight / Q000000981:diagnostic imaging / Q000208:ethnology / Q000378:metabolism; D010641:Phenotype; D015995:Prevalence; D011859:Radiography; D014481:United States / Q000453:epidemiology; D055815:Young Adult