title: The Wisconsin Epidemiologic Study of Diabetic Retinopathy XXIII: the twenty-five-year incidence of macular edema in persons with type 1 diabetes.
abstract: OBJECTIVE
  To examine the 25-year cumulative incidence of macular edema (ME) and its relation to various risk factors.
  
  
  METHODS
  Population-based study.
  
  
  METHODS
  A total of 955 insulin-taking persons living in an 11-county area in southern Wisconsin with type 1 diabetes diagnosed before age 30 years who participated in baseline examinations (1980-1982) and at least 1 of 4 follow-up (4-, 10-, 14-, and 25-year) examinations (n=891) or died before the first follow-up examination (n=64).
  
  
  METHODS
  Stereoscopic color fundus photographs were graded using the modified Airlie House classification and the Early Treatment Diabetic Retinopathy Study retinopathy severity scheme. Competing risk of death was included in statistical models.
  
  
  METHODS
  Incidence of ME and clinically significant ME (CSME).
  
  
  RESULTS
  The 25-year cumulative incidence was 29% for ME and 17% for CSME. Annualized incidences of ME were 2.3%, 2.1%, 2.3%, and 0.9% in the first, second, third, and fourth follow-up periods of the study, respectively. In univariate analyses, the incidence of ME was associated with male sex, more severe diabetic retinopathy, higher glycosylated hemoglobin, proteinuria, higher systolic and diastolic blood pressure, and more pack-years of smoking. Multivariate analyses showed that the incidence of ME was related to higher baseline glycosylated hemoglobin (hazard ratio [HR] per 1% 1.17; 95% confidence interval [CI], 1.10-1.25; P<0.001) and higher systolic blood pressure (HR per 10 mmHg 1.15; 95% CI, 1.04-1.26; P=0.004) and marginally to proteinuria (HR 1.43; 95% CI, 0.99-2.08; P=0.06).
  
  
  CONCLUSIONS
  These data show that relatively high 25-year cumulative rates of incidence of ME were related to glycemia and blood pressure. The lower risk of incident ME in the last period of the study may reflect recent improvement in care.
authors.affiliation: Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin 53726-2336, USA. kleinr@epi.ophth.wisc.edu
authors.forename: Ronald
authors.initials: R
authors.lastname: Klein
authors.forename: Michael D
authors.initials: MD
authors.lastname: Knudtson
authors.forename: Kristine E
authors.initials: KE
authors.lastname: Lee
authors.forename: Ronald
authors.initials: R
authors.lastname: Gangnon
authors.forename: Barbara E K
authors.initials: BE
authors.lastname: Klein
mesh_terms: D000293:Adolescent; D000328:Adult; D001786:Blood Glucose / Q000032:analysis; D001794:Blood Pressure; D002648:Child; D002675:Child, Preschool; D003922:Diabetes Mellitus, Type 1 / Q000453:epidemiology*; D003930:Diabetic Retinopathy / Q000145:classification / Q000453:epidemiology* / Q000503:physiopathology; D016021:Epidemiologic Studies; D005260:Female; D006442:Glycated Hemoglobin / Q000032:analysis; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D008269:Macular Edema / Q000145:classification / Q000453:epidemiology* / Q000503:physiopathology; D008297:Male; D015995:Prevalence; D012307:Risk Factors; D014922:Wisconsin / Q000453:epidemiology
chemical_list: D001786:Blood Glucose; D006442:Glycated Hemoglobin