Obesity is not associated with recurrent venous thromboembolism in elderly patients: Results from the prospective SWITCO65+ cohort study

BACKGROUND: Whether obesity is associated with recurrent venous thromboembolism (VTE) in elderly patients is unknown. OBJECTIVES: To examine the association between two obesity measures, the body mass index (BMI) and the waist circumference (WC), and recurrent VTE in elderly patients. PATIENTS/METHODS: We studied 986 patients aged ≥65 years with an acute VTE from a prospective multicenter cohort study (09/2009-12/2013). The BMI was determined and categorized as <25, 25 to <30, or ≥30 kg/m(2). The WC was categorized as <80 cm in women (w)/<94 cm in men (m), 80 to <88 cm (w)/94 to <102 cm (m), or ≥88 cm (w)/≥102 cm (m). We examined the association between the BMI and the WC and the time to a first symptomatic recurrent VTE using competing risk regression, adjusting for known risk factors of VTE recurrence and periods of anticoagulation. RESULTS: The mean follow-up was 28 months. The 3-year cumulative incidence of recurrent VTE did not vary by BMI and was 17.6% for a BMI <25 kg/m(2), 11.5% for a BMI 25 to <30 kg/m(2), and 16.9% for a BMI ≥30 kg/m(2) (P = 0.09). The 3-year cumulative incidence of recurrent VTE did not vary by WC. After adjustment, neither the BMI (sub-hazard ratio [SHR] 1.02, 95% confidence interval [CI 0.98–1.05]) nor the WC (SHR 1.01, 95% CI 0.99–1.02) was associated with recurrent VTE. CONCLUSIONS: Measures of body weight were not associated with recurrent VTE in our cohort. Obesity does not appear to be a predictor of recurrent VTE in the elderly.