title: Relationship between progression to AIDS and thrombophilic abnormalities in HIV infection.
abstract: BACKGROUND
  HIV-infected patients are at increased risk of venous and arterial thrombosis. We hypothesized that acquired thrombophilic abnormalities that could predispose to thrombosis are most pronounced in patients in advanced stages of HIV infection.
  
  
  METHODS
  We included 109 consecutive HIV-infected patients in the study and tested them twice for currently known thrombophilic abnormalities at an interval of at least 3 months (median, 3 months; range, 3-12 months). Detailed information was collected about the date of diagnosis of HIV infection, HIV treatment, and previous episodes of venous and arterial thrombosis.
  
  
  RESULTS
  After HIV infection was diagnosed, 16% of the patients experienced symptomatic thrombosis (venous, 10%; arterial, 6%). Repeated measurements established protein C deficiency in 9% of the patients, increased factor VIII concentrations in 41%, high fibrinogen concentrations in 22%, and free protein S deficiency in 60%. Median factor VIII concentrations were higher in patients with AIDS (CD4 cell counts <2 x 10(8)/L) than in patients with a non-AIDS-defining illness (2260 IU/L vs 1 490 IU/L; P < 0.001), whereas median free protein S concentrations were lower (450 IU/L vs 580 IU/L; P < 0.001). Developing AIDS was associated with increasing factor VIII concentrations and decreasing free protein S concentrations. Increasing factor VIII concentrations were correlated with increasing fibrinogen concentrations and decreasing free protein S concentrations.
  
  
  CONCLUSIONS
  Multiple acquired and persistent thrombophilic abnormalities are more frequently observed in HIV-infected patients than in the healthy population. The frequencies of these thrombophilic abnormalities increase with the progression to AIDS. These findings may contribute to the high prevalence of venous and arterial thrombosis in HIV-infected patients.
authors.affiliation: Division of Haemostasis, Thrombosis and Rheology and Division of Infectious Diseases, Department of Internal Medicine, University Medical Center Groningen (UMCG), Groningen, The Netherlands. w.lijfering@int.umcg.nl
authors.forename: Willem M
authors.initials: WM
authors.lastname: Lijfering
authors.forename: Herman G
authors.initials: HG
authors.lastname: Sprenger
authors.forename: Rita R
authors.initials: RR
authors.lastname: Georg
authors.forename: Piet A
authors.initials: PA
authors.lastname: van der Meulen
authors.forename: Jan
authors.initials: J
authors.lastname: van der Meer
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000150:complications / Q000503:physiopathology; D000328:Adult; D000368:Aged; D005260:Female; D015658:HIV Infections / Q000150:complications* / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D018570:Risk Assessment; D019851:Thrombophilia / Q000453:epidemiology / Q000209:etiology*; D013927:Thrombosis / Q000453:epidemiology / Q000209:etiology*; D020246:Venous Thrombosis / Q000453:epidemiology / Q000209:etiology