title: Cross-sectional associations of blood elements, clotting factors, nephropathy, and retinal outcomes in long duration type 1 diabetes.
abstract: OBJECTIVE
  To determine the association of blood elements, selected clotting factors, and nephropathy with proliferative diabetic retinopathy (PDR) and macular edema (ME) in those with long duration type 1 diabetes.
  
  
  METHODS
  Participants (N = 442) were seen in 2005-2007 at the 25-year follow-up of a population-based study of diabetic retinopathy, and were eligible for this analysis. Fundus photographs were graded using a standard retinopathy severity scheme. Laboratory measures included hematocrit, white blood cell and platelet counts, serum fibrinogen, interleukin-6, and von Willebrand factor.
  
  
  RESULTS
  In models including duration of diabetes, hypertension, and diabetic nephropathy, only hematocrit was marginally associated with decreased odds of PDR (odds ratio 0.87; 95% confidence interval 0.74-1.01; P for trend per quintile = 0.06). Stratifying by nephropathy status, in those with and without nephropathy, there were no significant associations of any laboratory measures with PDR or ME. None of the variables we examined were associated with ME in individuals with or without nephropathy.
  
  
  CONCLUSIONS
  In persons with long duration type 1 diabetes, none of the blood elements or clotting factors were associated with increased odds of PDR or ME. Investigation of common pathways that lead to diabetic nephropathy and diabetic retinal outcomes should be a research priority in efforts to prevent vision-threatening complications of diabetes and nephropathy.
authors.affiliation: Department of Ophthalmology and Visual Sciences, University of Wisconsin School of Medicine and Public Health, Madison, WI 53726-2336, USA. kleinb@epi.ophth.wisc.edu
authors.forename: Barbara E K
authors.initials: BE
authors.lastname: Klein
authors.forename: Ronald
authors.initials: R
authors.lastname: Klein
authors.forename: Kerri P
authors.initials: KP
authors.lastname: Howard
authors.forename: Kristine E
authors.initials: KE
authors.lastname: Lee
mesh_terms: D000328:Adult; D003430:Cross-Sectional Studies; D003922:Diabetes Mellitus, Type 1 / Q000097:blood / Q000453:epidemiology*; D003928:Diabetic Nephropathies / Q000097:blood / Q000453:epidemiology*; D003930:Diabetic Retinopathy / Q000097:blood / Q000453:epidemiology*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005340:Fibrinogen / Q000378:metabolism*; D006400:Hematocrit; D006801:Humans; D015850:Interleukin-6 / Q000097:blood*; D007958:Leukocyte Count; D008297:Male; D016017:Odds Ratio; D010976:Platelet Count; D014922:Wisconsin / Q000453:epidemiology; D014841:von Willebrand Factor / Q000378:metabolism*
chemical_list: C508600:IL6 protein, human; D015850:Interleukin-6; D014841:von Willebrand Factor; D005340:Fibrinogen