Summary
The EXCLAIM study enrolled hospitalised acutely ill medical patients with age >40
years and recently-reduced mobility into a trial of extended-duration anticoagulant
thromboprophylaxis. This post-hoc analysis evaluated the impact of age on patient
outcomes. After completion of open-label therapy with enoxaparin 40 mg once-daily
(10 ± 4 days), eligible patients underwent randomisation to receive double-blind therapy
of enoxaparin (n=2,975) or placebo (n=2,988) for 28 ± 4 days. During follow-up, the
venous thromboembolism (VTE) risk increased with age in both treatment groups. In
patients with age >75 years, those who received extended-duration enoxaparin had lower
incidence of VTE (2.5% vs 6.7%; absolute difference [AD] [95% confidence interval]:
−4.2% [−6.5, −2.0]), proximal deep-vein thrombosis (2.5% vs 6.6%; AD −4.1 % [−6.2,
−2.0]), and symptomatic VTE (0.3% vs 1.5%; AD −1.2% [−2.2, −0.3]), in comparison to
those who received placebo. In patients with age ≤75 years, those who received enoxaparin
had reduced VTE (2.4% vs 2.8%; AD −0.4% [−1.5, 0.7]) and symptomatic VTE (0.2% vs
0.7%; AD −0.6% [−1.0, −0.1]) in comparison to those who received placebo. In both
age subgroups, patients who received enoxaparin had increased rates of major bleeding
versus those who received placebo: age >75 years (0.6% vs 0.2%; AD +0.3% [−0.2, 0.9],
respectively); age ≤75 years (0.7% vs 0.2%; AD +0.5% [0.1, 0.9]). Patients in both
age subgroups that received enoxaparin had similar low bleeding rates (0.6% and 0.7%,
respectively). VTE risk increased with age, though the bleeding risk did not. Patients
with age >75 years had a more favourable benefit-to-harm profile than younger patients.
Keywords
Venous thromboembolism - pulmonary embolism - deep-vein thrombosis - enoxaparin -
thromboprophylaxis