Poster Session I: Epidemiology and public health

Abstract

P52 Protein Z levels and vascular thrombotic diseases: A meta-analysis F Sofi, F Cesari, S Fedi, GJ Broze, R Abbate, GF Gensini University of Florence, Florence, Italy, Washington University, Division of Hematology, St. Louis, United States of America Topic: Risk factors and risk prediction Objective: The relationship between protein Z levels and thrombosis is controversial. We performed a systematic review and meta-analysis of all the available studies to assess the association between protein Z and vascular thrombotic diseases. Methods: We conducted an electronic literature search through MedLine, Embase, Google Scholar, Web of Science, The Cochrane Library, bibliographies of retrieved articles and abstracts of congresses up to May, 2009. Studies were included if they analysed protein Z levels in patients with vascular thrombotic diseases. Results: After the review process 28 case-control studies (33 cohort of patients) were included in the final analysis. These studies included 4,218 patients with thrombotic diseases as compared to 4,778 controls. The cumulative analysis for all the studies under a fixed-effects model showed that patients with low protein Z levels are at increased risk of occurring a thrombotic event (OR 1.87, 95%CI 1.62-2.15; p<0.00001). By subgrouping studies according to the different type of the disease, low protein Z levels were found to be a significant risk factor for arterial vascular diseases (OR 1.86, 95%CI 1.51-2.27; p<0.00001), and pregnancy complications (OR 3.42, 95%CI 2.51-4.66; p<0.00001) whereas only a limited significance for venous thromboembolic diseases (OR 1.28, 95%CI 1.00-1.65; p1⁄40.05) was reported. Conclusion:This is the first meta-analysis that attempted to evaluate the role of protein Z on the occurrence of thrombotic events. The present results suggest, in an overall population of more than 4,000 patients, a possible implication for low levels of this coagulatory protein on the pathogenesis of thrombosis.