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Published on: September 9, 2012
Risk factors for a first thrombotic event in antiphospholipid antibody carriers: a prospective multicentre follow-up
Amelia Ruffatti1, Teresa Del Ross, Manuela Ciprian
1Rheumatology Unit, Department of Clinical and Experimental Medicine, University of Padua, Padua, Italy. amelia.ruffatti@unipd.it
Objectives:
To assess risk factors for a first thrombotic event in confirmed antiphospholipid (aPL) antibody carriers and to evaluate the efficacy of prophylactic treatments.
Methods:
Inclusion criteria were age 18-65 years, no history of thrombosis and two consecutive positive aPL results. Demographic, laboratory and clinical parameters were collected at enrolment, once a year during the follow-up and at the time of the thrombotic event, whenever that occurred.
Results:
258 subjects were prospectively observed between October 2004 and October 2008. The mean ± SD follow-up was 35.0 ± 11.9 months (range 1-48). A first thrombotic event (9 venous, 4 arterial and 1 transient ischaemic attack) occurred in 14 subjects (5.4%, annual incidence rate 1.86%). Hypertension and lupus anticoagulant (LA) were significantly predictive of thrombosis (both at p<0.05) and thromboprophylaxis was significantly protective during high-risk periods (p<0.05) according to univariate analysis. Hypertension and LA were identified by multivariate logistic regression analysis as independent risk factors for thrombosis (HR 3.8, 95% CI 1.3 to 11.1, p<0.05, and HR 3.9, 95% CI 1.1 to 14, p<0.05, respectively).
Conclusions:
Hypertension and LA are independent risk factors for thrombosis in aPL carriers. Thromboprophylaxis in these subjects should probably be limited to high-risk situations.
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