title: Thrombophilic risk factors in the pathogenesis of non-arteritic anterior ischemic optic neuropathy patients.
abstract: BACKGROUND
  Non-arteritic anterior ischemic optic neuropathy (N-AION) is caused by acute ischemic infarction of the optic nerve head, supplied by the posterior ciliary arteries. Thrombophilia is the tendency/predisposition to vascular thromboses of arteries and veins, and the existence of thrombophilic risk factors leads to blood hypercoagulability and potentially increased risk for thromboses.
  
  
  OBJECTIVE
  To investigate whether there is an association between N-AION and a wide spectrum of thrombophilic risk factors.
  
  
  METHODS
  Seventy-seven consecutive cases of confirmed N-AION and 60 age- and sex-matched consecutive controls constituted the study group. Fibrinogen levels, deficiency of proteins C, S, ATIII, lupus anticoagulant, activated protein C resistance, factor V Leiden, factor V H1299R, factor II G20210A, MTHFR C677T, MTHFR A1298C, GPIIIa A1/A2, and ACE I/D polymorphisms were analysed.
  
  
  RESULTS
  Statistical analysis of the plasma proteins in our study demonstrated that the only significant difference was the one concerning protein S levels. In particular, the mean value for N-AION patients was 78.8% +/- 21.2, and for the control group the mean value was 88% +/- 21.2 (p = 0.013). Despite the above-mentioned result, there was not any statistical difference between the two subgroups regarding actual protein S deficiency, as 9/77 (11.7%) patients and 4/60 (6.7%) controls had protein S levels below 60% (p = 0.32). In our study sample, homozygosity for MTHFR C677T polymorphism in the study group as a whole, and the presence of at least one A2 allele of GPIIIa in the subgroup of male patients as compared to healthy male controls, proved to be the most significant thrombophilic risk factors, with odds ratios of 16.78 (95% C.I 0.96-294.42, p = 0.054) and 4.6 (95% C.I 1.52-13.88, p = 0.007) respectively.
  
  
  CONCLUSIONS
  Screening for these polymorphisms would probably constitute a valuable procedure in N-AION patients, as they may have an important contribution to the pathogenesis of the disease.
authors.affiliation: University Eye Clinic of Ioannina, Kosti Palama 1, Anatoli, Ioannina, 45500, Greece.
authors.forename: Taxiarchis
authors.initials: T
authors.lastname: Felekis
authors.forename: Nikolaos I
authors.initials: NI
authors.lastname: Kolaitis
authors.forename: Georgios
authors.initials: G
authors.lastname: Kitsos
authors.forename: Georgios
authors.initials: G
authors.lastname: Vartholomatos
authors.forename: Konstantinos L
authors.initials: KL
authors.lastname: Bourantas
authors.forename: Ioannis
authors.initials: I
authors.lastname: Asproudis
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D050197:Atherosclerosis / Q000235:genetics / Q000378:metabolism; D001798:Blood Proteins / Q000235:genetics / Q000378:metabolism; D005260:Female; D006801:Humans; D006949:Hyperlipidemias / Q000235:genetics / Q000378:metabolism; D006973:Hypertension / Q000235:genetics; D008297:Male; D008875:Middle Aged; D018917:Optic Neuropathy, Ischemic / Q000209:etiology* / Q000235:genetics / Q000378:metabolism; D010088:Oxidoreductases / Q000235:genetics / Q000378:metabolism; D011110:Polymorphism, Genetic; D011446:Prospective Studies; D012307:Risk Factors; D019851:Thrombophilia / Q000453:epidemiology* / Q000235:genetics / Q000378:metabolism
chemical_list: D001798:Blood Proteins; D010088:Oxidoreductases