title: Diabetic vitrectomy in a large type 1 diabetes patient population: long-term incidence and risk factors.
abstract: OBJECTIVE
  Diabetic vitrectomy represents an end-point of diabetic retinopathy progression. This study was designed to estimate long-term incidence of diabetic vitrectomy and associated risk factors.
  
  
  METHODS
  Retrospective review of prospectively collected data from a large diabetes centre between 1996 and 2010. Surgical history was obtained from The Danish National Patient Register.
  
  
  RESULTS
  The population consisted of 3980 patients with type 1 diabetes. Median follow-up was 10.0 years. In total, 106 patients underwent diabetic vitrectomy in the observation period. Surgery indications were nonclearing vitreous haemorrhage (43%) or tractional retinal detachment (57%). The cumulative incidence rates of diabetic vitrectomy were 1.6% after 5 years and 2.9% after 10 years. When excluding patients with no or mild diabetic retinopathy, the corresponding rates were higher; 3.7% and 6.4%, respectively (p < 0.001, log-rank test). The risk of reaching diabetic vitrectomy increased in patients experiencing glycosylated haemoglobin A1c > 75 mmol/mol in the observation period (p < 0.001, hazard ratio: 3.9, Cox regression analysis). Systolic blood pressure ≥ 140 mmHg, diastolic blood pressure ≥ 90 mmHg, diabetes duration, age, gender and nephropathy were not associated with an increased risk of reaching diabetic vitrectomy (p > 0.05 for all variables).
  
  
  CONCLUSIONS
  Diabetic vitrectomy is rarely required in a type 1 diabetes population with varying degrees of retinopathy, but the risk increases markedly with poor metabolic control.
authors.affiliation: Department of Ophthalmology, Glostrup Hospital, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Christoffer
authors.initials: C
authors.lastname: Ostri
authors.forename: Morten
authors.initials: M
authors.lastname: la Cour
authors.forename: Henrik
authors.initials: H
authors.lastname: Lund-Andersen
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001786:Blood Glucose / Q000378:metabolism; D001794:Blood Pressure; D003718:Denmark / Q000453:epidemiology; D003922:Diabetes Mellitus, Type 1 / Q000097:blood / Q000453:epidemiology* / Q000601:surgery; D003928:Diabetic Nephropathies / Q000453:epidemiology; D003930:Diabetic Retinopathy / Q000097:blood / Q000453:epidemiology* / Q000601:surgery; D005260:Female; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D015994:Incidence; D017075:Laser Coagulation; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012042:Registries; D012189:Retrospective Studies; D012307:Risk Factors; D014821:Vitrectomy / Q000706:statistics & numerical data*; D055815:Young Adult
chemical_list: D001786:Blood Glucose; D006442:Glycated Hemoglobin; C517652:hemoglobin A1c protein, human
keywords: diabetes; diabetic retinopathy; diabetic vitrectomy; incidence; metabolic control; panretinal laser; risk factors; scatter laser; vitrectomy