title: Risk factors for decline in IQ in youth with type 1 diabetes over the 12 years from diagnosis/illness onset.
abstract: OBJECTIVE
  This study examined illness-related change in intelligence quotient (IQ) in a cohort of youth with type 1 diabetes studied prospectively from disease onset in childhood to follow-up 12 years later in late adolescence/early adulthood.
  
  
  METHODS
  Participants included type 1 diabetes patients (n = 95; mean age at follow-up 21.3 years) and healthy control participants (HCs; n = 67; mean age at follow-up 21.0 years) from a cohort followed prospectively. Measures included Wechsler Preschool and Primary Scale of Intelligence-Revised, Wechsler Intelligence Scale for Children-Revised, and Wechsler Abbreviated Scale of Intelligence and prospective collection of data on metabolic control history.
  
  
  RESULTS
  Young people with type 1 diabetes showed greater decline in verbal IQ (VIQ) and full-scale IQ (FSIQ), but not performance IQ (PIQ), than HCs. Within the diabetes group, a younger age at diabetes onset was associated with a decline in PIQ and FSIQ (P ≤ 0.001). A history of hypoglycemic seizures was associated with a decline in VIQ (P = 0.002). Long-term metabolic control was not associated with changes in IQ. Interaction terms were not significant, suggesting no moderating effect of one diabetes-related variable over another.
  
  
  CONCLUSIONS
  The presence of diabetes may negatively influence some aspects of IQ over time. Specific illness risk factors, such as an earlier age of disease onset and a history of hypoglycemic seizures, appear to put the young person at greater risk. Academic progress of children identified as at risk should be monitored and educational supports provided if necessary.
authors.affiliation: Telethon Kids Institute, University of Western Australia, Perth, Australia ashleigh.lin@telethonkids.org.au.
authors.forename: Ashleigh
authors.initials: A
authors.lastname: Lin
authors.affiliation: Department of Psychology, Royal Children's Hospital, Melbourne, Australia Department of Endocrinology and Diabetes, Royal Children's Hospital, Melbourne, Australia Murdoch Childrens Research Institute, Royal Children's Hospital, Melbourne, Australia.
authors.forename: Elisabeth A
authors.initials: EA
authors.lastname: Northam
authors.affiliation: Department of Endocrinology and Diabetes, Royal Children's Hospital, Melbourne, Australia Murdoch Childrens Research Institute, Royal Children's Hospital, Melbourne, Australia Department of Paediatrics, University of Melbourne, Royal Children's Hospital, Melbourne, Australia.
authors.forename: George A
authors.initials: GA
authors.lastname: Werther
authors.affiliation: Department of Endocrinology and Diabetes, Royal Children's Hospital, Melbourne, Australia Murdoch Childrens Research Institute, Royal Children's Hospital, Melbourne, Australia Department of Paediatrics, University of Melbourne, Royal Children's Hospital, Melbourne, Australia.
authors.forename: Fergus J
authors.initials: FJ
authors.lastname: Cameron
mesh_terms: D000293:Adolescent; D017668:Age of Onset; D001786:Blood Glucose / Q000378:metabolism; D016022:Case-Control Studies; D002648:Child; D003922:Diabetes Mellitus, Type 1 / Q000097:blood / Q000523:psychology*; D016883:Diabetic Ketoacidosis / Q000097:blood / Q000523:psychology; D005260:Female; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D007360:Intelligence; D008297:Male; D011446:Prospective Studies; D012307:Risk Factors; D014888:Wechsler Scales; D055815:Young Adult
chemical_list: D001786:Blood Glucose; D006442:Glycated Hemoglobin