title: Association of Exposure to Di-2-Ethylhexylphthalate Replacements With Increased Insulin Resistance in Adolescents From NHANES 2009-2012.
abstract: BACKGROUND
  Di-isononyl phthalate (DINP) and di-isodecyl phthalate (DIDP) are environmental chemicals increasingly used to replace di-2-ethylhexylphthalate (DEHP) and commonly found in processed foods. Phthalate exposures, in particular DEHP, have been associated with insulin resistance in adolescents, but there are no data regarding the two substitutes, DINP and DIDP.
  
  
  OBJECTIVE
  This study aimed to examine associations of DINP, DIDP, and DEHP with insulin resistance outcomes.
  
  
  METHODS
  This was a cross-sectional analysis of 2009-2012 National Health and Nutrition Examination Surveys (NHANES) composed of 356 fasting 12-19-year-olds.
  
  
  METHODS
  Insulin resistance as a categorical outcome expressed as homeostatic model assessment of insulin resistance (HOMA-IR), using a cut point of 4.39 to define insulin resistance. We also examined continuous HOMA-IR as an outcome in secondary analyses.
  
  
  RESULTS
  Controlling for demographic and behavioral factors, diet, age, body mass index, and urinary creatinine, for each log increase in DINP metabolite, a 0.08 (P = .001) increase in HOMA-IR was identified. Compared with the first tertile of DINP (23.4% adjusted prevalence), the third tertile was associated with a 34.4% prevalence (95% confidence interval [CI], 27.3-41.6%; P = .033) of insulin resistance. Similarly, compared with the first tertile of DEHP (20.5% adjusted prevalence), the third tertile had 37.7% prevalence (95% CI 29.8-45.6%; P = .003).
  
  
  CONCLUSIONS
  Urinary DINP concentrations were associated with increased insulin resistance in this cross-sectional study of adolescents. The previously identified association of DEHP with insulin resistance was also confirmed. Further, longitudinal studies are needed to confirm these associations, with the possibility to assess opportunities for intervention.
authors.affiliation: Departments of Pediatrics (T.M.A., L.T.), Environmental Medicine (L.T.), and Population Health (L.T.), New York University School of Medicine, New York, New York 10016; New York University Wagner School of Public Service (L.T.), New York, New York 10012; New York University Steinhardt School of Culture, Education and Human Development, Department of Nutrition, Food & Public Health (L.T.), New York, New York 10003; and New York University Global Institute of Public Health (L.T.), New York, New York 10003.
authors.forename: Teresa M
authors.initials: TM
authors.lastname: Attina
authors.affiliation: Departments of Pediatrics (T.M.A., L.T.), Environmental Medicine (L.T.), and Population Health (L.T.), New York University School of Medicine, New York, New York 10016; New York University Wagner School of Public Service (L.T.), New York, New York 10012; New York University Steinhardt School of Culture, Education and Human Development, Department of Nutrition, Food & Public Health (L.T.), New York, New York 10003; and New York University Global Institute of Public Health (L.T.), New York, New York 10003.
authors.forename: Leonardo
authors.initials: L
authors.lastname: Trasande
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D003430:Cross-Sectional Studies; D004051:Diethylhexyl Phthalate / Q000378:metabolism / Q000633:toxicity / Q000652:urine*; D004781:Environmental Exposure / Q000032:analysis* / Q000706:statistics & numerical data*; D005260:Female; D019649:Food Industry / Q000379:methods; D006801:Humans; D007333:Insulin Resistance; D008297:Male; D009749:Nutrition Surveys; D010795:Phthalic Acids / Q000378:metabolism / Q000633:toxicity / Q000652:urine*; D055815:Young Adult
chemical_list: D010795:Phthalic Acids; C012125:diisononyl phthalate; D004051:Diethylhexyl Phthalate; C042080:diisodecyl phthalate