title: Retinal vascular geometry predicts incident renal dysfunction in young people with type 1 diabetes.
abstract: OBJECTIVE
  To examine the relationship between retinal vascular geometry parameters and development of incident renal dysfunction in young people with type 1 diabetes.
  
  
  METHODS
  This was a prospective cohort study of 511 adolescents with type 1 diabetes of at least 2 years duration, with normal albumin excretion rate (AER) and no retinopathy at baseline while attending an Australian tertiary-care hospital. AER was quantified using three overnight, timed urine specimen collections and early renal dysfunction was defined as AER >7.5 μg/min. Retinal vascular geometry (including length-to-diameter ratio [LDR] and simple tortuosity [ST]) was quantified from baseline retinal photographs. Generalized estimating equations were used to examine the relationship between incident renal dysfunction and baseline venular LDR and ST, adjusting for age, diabetes duration, glycated hemoglobin (A1C), blood pressure (BP), BMI, and cholesterol.
  
  
  RESULTS
  Diabetes duration at baseline was 4.8 (IQR 3.3-7.5) years. After a median 3.7 (2.3-5.7) years follow-up, 34% of participants developed incident renal dysfunction. In multivariate analysis, higher retinal venular LDR (odds ratio 1.7, 95% CI 1.2-2.4; quartile 4 vs. 1-3) and lower venular ST (1.6, 1.1-2.2; quartile 1 vs. 2-4) predicted incident renal dysfunction.
  
  
  CONCLUSIONS
  Retinal venular geometry independently predicted incident renal dysfunction in young people with type 1 diabetes. These noninvasive retinal measures may help to elucidate early mechanistic pathways for microvascular complications. Retinal venular geometry may be a useful tool to identify individuals at high risk of renal disease early in the course of diabetes.
authors.affiliation: The Children’s Hospital at Westmead, Westmead, Australia.
authors.forename: Paul Z
authors.initials: PZ
authors.lastname: Benitez-Aguirre
authors.forename: Muhammad Bayu
authors.initials: MB
authors.lastname: Sasongko
authors.forename: Maria E
authors.initials: ME
authors.lastname: Craig
authors.forename: Alicia J
authors.initials: AJ
authors.lastname: Jenkins
authors.forename: Janine
authors.initials: J
authors.lastname: Cusumano
authors.forename: Ning
authors.initials: N
authors.lastname: Cheung
authors.forename: Tien Yin
authors.initials: TY
authors.lastname: Wong
authors.forename: Kim C
authors.initials: KC
authors.lastname: Donaghue
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D003922:Diabetes Mellitus, Type 1 / Q000150:complications / Q000453:epidemiology*; D005260:Female; D006801:Humans; D007674:Kidney Diseases / Q000453:epidemiology* / Q000209:etiology; D008297:Male; D015999:Multivariate Analysis; D011446:Prospective Studies; D012171:Retinal Vessels / Q000002:abnormalities*; D055815:Young Adult