BACKGROUND: In patients with incident heart failure, the risk of venous thromboembolism (VTE), defined as pulmonary embolism (PE) and/or deep venous thrombosis (DVT), is sparsely described, especially potential sex differences. We conducted an observational study to evaluate risk of VTE among male and female heart failure patients.
METHODS: Population-based cohort study of patients diagnosed with incident heart failure during 2000-2015, identified by record linkage between nationwide registries in Denmark. Using a pseudo-value approach, we calculated relative risks [RR] of VTE at 1 and 3 years of follow-up. Crude VTE risk for males and females are reported and contrasted after adjustment for established clinical risk factors for VTE.
RESULTS: A total of 32,330 heart failure patients were included, of which 15,238 (47%) were females. For the combined endpoint of VTE, female sex was associated with a higher risk (1-year adjusted RR: 1.30, 95% confidence interval [CI]: 0.97-1.73; 3-year adjusted RR: 1.34, 95% CI: 1.07-1.67) compared to male patients. For the individual endpoints of PE and DVT after 1-year of follow-up, female sex was only associated with a higher risk of PE and not DVT, compared to male patients. However, female sex was associated with a higher risk of both PE and DVT after 3 years of follow-up.
CONCLUSIONS: Among incident heart failure patients, female sex is associated with a higher risk of VTE, mainly driven by an excess risk of PE. This finding may help improve clinical decision-making regarding VTE prophylaxis in patients with heart failure.