Incidence of arteriovenous thrombosis and the role of anticardiolipin antibodies in hemodialysis patients.
BACKGROUND
Fistula thrombosis in patients on maintenance hemodialysis is an important morbidity factor. Arterial or venous thrombotic events have been described as complications in patients on regular hemodialysis and positive titers of anticardiolipin antibodies (ACLA). This study was designed to evaluate the prevalence of ACLA in hemodialysis patients and it's relation to arteriovenous fistula (AVF) thrombosis.


METHODS
218 patients with AVF on maintenance hemodialysis were studied prospectively during a period of 14 months for any episode of AVF thrombosis (AVFT), after ACLA was assayed by ELISA in 171 ones. Other risk factors for thrombosis such as presence of diabetes, hypotension during dialysis, using of erythropoietin (rEpo), fistula site, gender, age, dialysis duration, and type of dialyser membrane were accessed.


RESULTS
56% of the patients had IgG ACLA = 10 GPL which was significantly correlated with dialysis duration (23.18 +/- 24.56 months in patients with ACLA = 10 GPL vs 37.73 +/- 36.35 months in patients with 20 = IgG ACLA < 40 GPL). Within 14 months follow up, 39 episodes of AVFT occurred in 34 patients (15.8%). Dialysis duration prior to start of study was 29.16 +/- 22.04 months. In our patients radiocephalic AVFs showed more thrombosis than brachiocephalic ones (23% vs 10%, p = 0.01 by Chi-square). Age more than 50 years old was a risk factor for AVFT (p = 0.034 by Chi-square). Also erythropoietin use (p = 0.011 by chi-square) and ultrafiltration more than 3 liters (average value of 14 months) were correlated with AVFT (p = 0.042 by Chi-square), but there wasn't any correlation between diabetes, presence of ACLA, hypotension during dialysis, gender, and dialysis membranes with AVFT. Ultimately, logistic regression analysis of factors associated with thrombosis was done and only fistula site (p = 0.015, O.R. = 2.87), and Eprex use (p = 0.031, O.R. = 4.05) showed significant correlation with AVFT.


CONCLUSIONS
Although incidence of anticardiolipin antibodies was high in our patients, we found no correlation between IgG ACLA and AVFT. Instead, we found that radiocephalic fistulas and Eprex injection were risk factors for AVFT.
Jamshid
Roozbeh
R
Department of Medicine, Division of Nephrology, Shiraz University of Medical Science, Shiraz, Iran. roozbehj@hotmail.com
Reza
Serati Ali
SA
Abbas
Ghaderi
G
Raha
Afshariani
A
D017153:Antibodies, Anticardiolipin / Q000097:blood*; D002408:Catheters, Indwelling / Q000009:adverse effects*; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011446:Prospective Studies; D006435:Renal Dialysis / Q000295:instrumentation; D013927:Thrombosis / Q000097:blood* / Q000453:epidemiology* / Q000209:etiology
D017153:Antibodies, Anticardiolipin