title: The case for biennial retinopathy screening in children and adolescents.
abstract: OBJECTIVE
  Current guidelines recommend annual retinopathy screening 2 years after onset (for pubertal-onset type 1 diabetes) and after 5 years (or age 11, whichever is earlier) for prepubertal onset. Our aim was to describe the natural history of retinopathy and to explore optimal retinal screening intervals for children and adolescents (aged <20 years) screened according to these guidelines.
  
  
  METHODS
  More than 1,000 children and adolescents, followed longitudinally, were screened for retinopathy using seven-field stereoscopic fundus photography through dilated pupils. Of these, 668 had baseline and follow-up retinal screening. Using generalized estimating equations, we compared the risk of retinopathy with baselines at yearly intervals, in older and younger groups, in higher risk groups (diabetes duration >10 years or HbA(1c) >10% at any screening), and after stratification </=10 and <10 years in duration.
  
  
  RESULTS
  After 1 year, retinopathy did not increase significantly in the older group (n = 618, median HbA(1c) 8.7%, range 8.0-9.5), younger group (n = 50, median HbA(1c) 8.5%, range 8.0-9.2), or the higher-risk groups. Retinopathy increased significantly after 2 years in the older group (P = 0.003) but not until 6 years in the younger group (P = 0.01). In the group with HbA(1c) >10% recorded at any visit, retinopathy increased significantly after 2 years (P = 0.001) but not until 3 years in the group whose HbA(1c) was always </=10% (P = 0.003). After the second eye assessment, retinopathy did not increase significantly until 3 and 6 years later in the older and younger groups, respectively (P = 0.028 and 0.014).
  
  
  CONCLUSIONS
  These results suggest that adolescents (in reasonable metabolic control) could safely be screened every 2 years rather than the currently recommended 1-year interval. In younger children, the next screening interval could be >2 years later. Individuals with especially poor control, duration >10 years, or significant retinopathy should be screened more frequently.
authors.affiliation: Institute of Endocrinology and Diabetes, The Children's Hospital at Westmead, Locked Bag 4001, Sydney, NSW 2145, Australia. annm4@chw.edu.au
authors.forename: Ann
authors.initials: A
authors.lastname: Maguire
authors.forename: Albert
authors.initials: A
authors.lastname: Chan
authors.forename: Janine
authors.initials: J
authors.lastname: Cusumano
authors.forename: Stephen
authors.initials: S
authors.lastname: Hing
authors.forename: Maria
authors.initials: M
authors.lastname: Craig
authors.forename: Martin
authors.initials: M
authors.lastname: Silink
authors.forename: Neville
authors.initials: N
authors.lastname: Howard
authors.forename: Kim
authors.initials: K
authors.lastname: Donaghue
mesh_terms: D000293:Adolescent; D002648:Child; D003922:Diabetes Mellitus, Type 1; D003930:Diabetic Retinopathy / Q000453:epidemiology* / Q000517:prevention & control*; D018450:Disease Progression; D005451:Fluorescein Angiography; D006801:Humans; D008403:Mass Screening; D009517:New South Wales / Q000453:epidemiology