title: β-cell autoimmunity in overweight non-diabetic youth: any implications?
abstract: OBJECTIVE
  The presence of β-cell antibodies is associated with a high risk of type 1 diabetes. With increasing rates of obesity, the distinction between obese T1DM and T2DM has become difficult. Moreover, increasing body mass index (BMI) in at-risk children has been proposed not only as a possible contributor to T1DM by increasing insulin resistance, but also as exerting an effect via the immunomodulatory properties of certain adipokines. This study aimed to determine prevalence of β-cell autoantibodies (AA) in overweight non-diabetic children and assess insulin sensitivity and secretion derived from an oral glucose tolerance test (OGTT) in those with vs. without ß-cell AA.
  
  
  METHODS
  A total of 357 overweight (BMI > 85%) youths underwent OGTTs, dual energy X-ray absorptiometry (DEXA) and measurement of GAD65 and IA-2 AA according to the NIDDK harmonization assay. Using the same methodology, AA were measured in 90 normal weight, non-diabetic individuals.
  
  
  RESULTS
  About 1.9% of overweight and 4.4% of control normal weight children had evidence of β-cell autoimmunity, with GAD65 AA detected in all subjects but none with IA-2. Youth with positive vs. those with negative AA had higher leptin/adiponectin ratio, glucose at 60 min and C-peptide at 90 min.
  
  
  CONCLUSIONS
  These findings suggest that the prevalence of β-cell AA in overweight youth may be similar to that in non-overweight children. Further studies using standardized methods are required.
authors.affiliation: Division of Pediatric Endocrinology, Children's Hospital of Pittsburgh, Pittsburgh, PA 15201, USA. ingrid.libman@chp.edu
authors.forename: Ingrid M
authors.initials: IM
authors.lastname: Libman
authors.forename: E
authors.initials: E
authors.lastname: Barinas-Mitchell
authors.forename: S
authors.initials: S
authors.lastname: Marcovina
authors.forename: F
authors.initials: F
authors.lastname: Bacha
authors.forename: T
authors.initials: T
authors.lastname: Hannon
authors.forename: H
authors.initials: H
authors.lastname: Tfayli
authors.forename: S J
authors.initials: SJ
authors.lastname: Lee
authors.forename: S
authors.initials: S
authors.lastname: Bansal
authors.forename: R
authors.initials: R
authors.lastname: Robertson
authors.forename: S
authors.initials: S
authors.lastname: Arslanian
mesh_terms: D000293:Adolescent; D001323:Autoantibodies / Q000097:blood*; D016022:Case-Control Studies; D002648:Child; D005260:Female; D005951:Glucose Tolerance Test; D006801:Humans; D007328:Insulin / Q000378:metabolism; D007333:Insulin Resistance; D000078790:Insulin Secretion; D050417:Insulin-Secreting Cells / Q000276:immunology*; D008297:Male; D050177:Overweight / Q000276:immunology*
chemical_list: D001323:Autoantibodies; D007328:Insulin