Anticoagulant treatment of cancer patients with pulmonary embolism in the real world: Actual use of low-molecular-weight heparin in cancer

BACKGROUND: Since 2004, guidelines recommend long-term treatment with low-molecular-weight heparin (LMWH) in patients with cancer and pulmonary embolism (PE). We assessed the proportion of cancer patients with PE actually treated with LMWH and the duration of anticoagulant treatment in the Netherlands. METHODS: A retrospective cohort study in patients that were hospitalised for PE between 1998-2008. Patients with PE were selected from national hospital discharge records, after linkage to a national pharmacy database. Cancer patients with PE were matched for age, sex and year of diagnosis of PE to subjects with PE without cancer. RESULTS: 600 cancer patients with PE were matched to 1200 patients with PE without cancer. Long-term LMWH was prescribed in 82 (13.7%) of the cancer patients and in eight (0.7%) of the cancer-free patients (p < 0.001); all the other patients received vitamin K antagonists (VKA). From 1998-2008, there was an increase in the use of LMWH in cancer patients: in 2007-2008, LMWH was prescribed in 42 (32%) cases, compared with one (1.7%) of the cancer patients with PE in 1998-1999. Median duration of treatment was 5.8 months (interquartile range 3.1-8.8) in cancer patients, compared with 7.0 months (4.9-11) in patients without cancer (p < 0.001), a difference that persisted after adjustment for mortality.