title: Altered fibrin-clot properties are associated with retinopathy in type 2 diabetes mellitus.
abstract: OBJECTIVE
  The development and progression of diabetic retinopathy (DR) in type 2 diabetes mellitus (T2DM) have been associated with poor glycaemic control, long disease duration and other clinical features. However, the pathogenesis of the complication is still poorly understood. As the formation of dense fibrin clots resistant to lysis has been described in diabetes patients, this study tested the hypothesis that altered clot structure and function are associated with DR in T2DM patients.
  
  
  METHODS
  The study included 101 T2DM subjects without DR (NDR) and 60 with DR. Plasma fibrin-clot permeation was assessed using a pressure-driven system, and expressed as the permeation coefficient (K(s)), indicating pore size, and as the time required for a 50% decrease in clot turbidity (t(50%)) as a marker of susceptibility to fibrinolysis. All patients underwent ophthalmological examination. Clinical and biochemical co-variables were also measured. Determinants of DR were identified using stepwise, multivariable, logistic-regression analyses.
  
  
  RESULTS
  Patients with DR had lower clot permeability (K(s): 6.15 ± 1.18 vs. 7.53 ± 1.24 10(-9) cm(2); P < 0.0001) and slower fibrin-clot lysis (t(50%): 10.12 ± 1.24 vs. 9.12 ± 1.4 min; P < 0.0001) than NDR subjects. Logistic analysis revealed associations between DR and K(s), t(50%), fasting glucose and diabetes duration, as well as insulin treatment and statin non-use (P < 0.05). After adjusting for these variables as well as for age and gender, associations between K(s) and t(50%) with DR proved to be significant.
  
  
  CONCLUSIONS
  Formation of compact fibrin clots and impaired clot lysis are both associated with DR in T2DM patients. However, it is unclear whether these abnormalities lead to the development of DR or merely constitute a marker of its presence.
authors.affiliation: Department of Metabolic Diseases, Jagiellonian University Medical College, 15 Kopernika Street, 21-501, Krakow, Poland.
authors.forename: M
authors.initials: M
authors.lastname: Walus-Miarka
authors.forename: P
authors.initials: P
authors.lastname: Wolkow
authors.forename: K
authors.initials: K
authors.lastname: Cyganek
authors.forename: B
authors.initials: B
authors.lastname: Mirkiewicz-Sieradzka
authors.forename: M T
authors.initials: MT
authors.lastname: Malecki
authors.forename: A
authors.initials: A
authors.lastname: Undas
mesh_terms: D015415:Biomarkers / Q000378:metabolism; D003924:Diabetes Mellitus, Type 2 / Q000378:metabolism* / Q000503:physiopathology; D003925:Diabetic Angiopathies / Q000378:metabolism* / Q000503:physiopathology; D003930:Diabetic Retinopathy / Q000378:metabolism* / Q000503:physiopathology; D005260:Female; D005337:Fibrin / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012307:Risk Factors
chemical_list: D015415:Biomarkers; D005337:Fibrin