title: Statins, aspirin and risk of venous thromboembolic events in breast cancer patients.
abstract: Venous thromboembolic events (VTE's) are associated with decreased survival in breast cancer patients. Studies suggested that statins reduce the risk of VTE's in the general population. Low dose Aspirin reduces risk of VTE's in high risk populations. The Breast Cancer in Northern Israel Study is a case-control study of consecutive breast cancer cases diagnosed in northern Israel and matched controls. The present analysis was limited to cases with breast cancer enrolled in the study. Data was extracted from Clalit Health Services (CHS) database and from computerized pharmacy records. Out of 3,585 patients enrolled, 261 (7.3%) had a VTE during median follow up of 4.2 years. The 1 and 2 year cumulative incidence was 2.64 and 3.65%. 55.7% of patients used statins, predominantly simvastatin (75.8%). 44.5% used aspirin. In multivariate analysis neither statins nor aspirin use was associated with a reduced risk for a VTE. Unadjusted HR for statin and aspirin was 1.461 (1.018-2.096) and 1.293 (0.846-1.976), respectively, and the adjusted HR were 0.86 (0.648-1.14) and 1.013 (0.737-1.392). Results were similar when only simvastatin use was assessed. Metastatic disease, chemotherapy, age, BMI and presence of comorbidities were significantly associated with risk of VTE's. Our study is the first to look at the effect of statins and aspirin on the incidence of VTE's in patients with breast cancer. In our cohort, statin and aspirin use did not decrease the risk for a VTE. Our results might be explained by use of low potency statins (simvastatin and pravastatin) and by alternate mechanisms for VTE formation in patients with cancer.
authors.affiliation: Department of Oncology, Clalit Health Services, Lin and Carmel Medical Centers, 35 Rotchild St., Haifa, Israel, ayeletshai1@gmail.com.
authors.forename: Ayelet
authors.initials: A
authors.lastname: Shai
authors.forename: Hedy S
authors.initials: HS
authors.lastname: Rennert
authors.forename: Ofer
authors.initials: O
authors.lastname: Lavie
authors.forename: Muona
authors.initials: M
authors.lastname: Ballan-Haj
authors.forename: Arie
authors.initials: A
authors.lastname: Bitterman
authors.forename: Mariana
authors.initials: M
authors.lastname: Steiner
authors.forename: Shoshana
authors.initials: S
authors.lastname: Keren
authors.forename: Gad
authors.initials: G
authors.lastname: Rennert
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D001241:Aspirin / Q000008:administration & dosage*; D015992:Body Mass Index; D001943:Breast Neoplasms / Q000453:epidemiology*; D016022:Case-Control Studies; D016208:Databases, Factual; D005260:Female; D005343:Fibrinolytic Agents / Q000008:administration & dosage*; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000008:administration & dosage*; D007557:Israel; D008875:Middle Aged; D012307:Risk Factors; D013923:Thromboembolism / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control
chemical_list: D005343:Fibrinolytic Agents; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D001241:Aspirin