Association between cardiovascular risk factors and venous thromboembolism in the elderly

Background: The preponderance of the evidence supports no association between traditional cardiovascular risk factors and venous thromboembolism (VTE), other than obesity. There are limited data in older people. Objectives: To investigate whether cardiovascular risk factors (body mass index, smoking, alcohol intake, hypertension, and diabetes) are associated with the risk of VTE in elderly and to assess the combined effect between cardiovascular risk factors and genetic risk factors for VTE (factor V Leiden/prothrombin 20210A, positive family history of VTE, and non-O blood group). Methods: The Age and Thrombosis, Acquired and Genetic risk factors in the Elderly study is a multicenter case-control study performed in Vermont, USA and Leiden, the Netherlands, comprising 401 cases with first VTE and 431 control subjects, all aged >= 70 years. To assess the risk of VTE, odds ratios (OR) with 95% confidence intervals (Cis) were calculated, adjusting for potential confounders. Results: Both height and weight were positively associated with VTE risk: the ORs were 2.2 (95% CI, 1.2-3.9) and 1.5 (95% CI, 1.0-2.4) in the top quartile for height and weight separately. This risk was more pronounced for unprovoked VTE. Smoking, alcohol intake, and diabetes were not associated with VTE. Higher systolic and diastolic blood pressure and hypertension were associated with a decreased risk of VTE. In the presence of a genetic predisposition, height and weight further increased the risk of VIE. Conclusions: In the elderly, height and weight are positively associated with the risk of VTE. With genetic predisposition, higher levels of height and weight further increase the risk of VTE.