Low-molecular-weight heparin was more cost-effective than unfractionated heparin for treating deep venous thrombosis in several clinical settings
ACP J Club. 1999 Mar-April;130:53. doi:10.7326/ACPJC-1999-130-2-053
Rodger M, Bredeson C, Wells PS, et al. Cost-effectiveness of low-molecular-weight heparin and unfractionated heparin in treatment of deep vein thrombosis. CMAJ. 1998 Oct 20;159:931-8.
What is the relative cost-effectiveness of 4 treatment strategies for deep venous thrombosis (DVT) (unfractionated heparin [UFH] for inpatients, low- molecular-weight heparin [LMWH] for inpatients, LMWH in a clinic setting for eligible patients and LMWH for the patients who needed hospital treatment, and LMWH in a clinic setting for eligible patients and UFH for the patients who needed hospital treatment)?
A decision-analytic incremental cost-effectiveness analysis.
A tertiary teaching hospital in Ottawa, Ontario, Canada.
All patients who had been hospitalized with a confirmed primary or secondary discharge diagnosis of DVT in 1995 to 1996 (n = 105). By using criteria from previous controlled trials, chart analysis showed that 56 patients (mean age 56 y) were eligible for outpatient clinic treatment and 49 patients (mean age 69 y) required hospital treatment.
Patient data were used to assess theoretical treatment outcomes and costs with all 4 strategies using meta-analysis. All patients were followed for 3 months.
Main cost and outcome measures
Meta-analysis provided data on recurrences of DVT, major hemorrhage, and mortality. Actual costs for UFH were taken from charts. Costs for initial treatment, major hemorrhage, and recurrences within 3 months (drugs, monitoring, inpatient costs based on charts, and clinic costs for injections and assessments) were included. Recurrence costs were based on actual costs of treating with UFH. Costs were in 1995 Canadian (Cdn) dollars. Sensitivity analyses were done.
Meta-analysis showed that LMWH compared with UFH reduced the risk for recurrence (4.4% vs 7.0%, P < 0.05) and death (4.1% vs 6.0%, P < 0.05) and showed a trend toward decreased major hemorrhage (1.2 vs 2.3%). Base-case analyses showed that UFH had case costs of Cdn $3313/inpatient and a 7% mortality rate at 3 months and that LMWH had costs of $3150/inpatient and a 4.7% mortality rate. Outpatient LMWH and inpatient UFH had costs of $2634/patient and a 6.0% mortality rate; outpatient LMWH and inpatient LMWH had costs of $2546/patient and a mortality rate of 4.7%. Sensitivity analyses did not change the results of the study.
In hospital, clinic, or home settings, low-molecular-weight heparin was more cost-effective than unfractionated heparin for the treatment of deep venous thrombosis.
Source of funding: No external funding.
For correspondence: Dr. M.A. Rodger, Ottawa General Hospital, Suite 7209, 501 Smyth Road, Ottawa, Ontario K1H 8L6, Canada. FAX 613-737-8861.
Rodger and colleagues confirm that LMWH is more cost-effective than UFH. They used meta-analysis to evaluate the efficacy and safety and patient-specific case-costing data to measure the costs. Their results are not surprising because all previous studies have concluded that LMWH was at least as effective as UFH and had a lower rate of complications, had shorter nursing time, and required less laboratory monitoring. Although the meta-analysis methods were not explained and the cost evaluation was based on a single center, these results are directly useful for the treatment of any patient with DVT. Outpatient treatment with LMWH is preferred.
The next steps for optimization of the treatments with LMWH will depend on answers to the following questions: Will the cost for the treatment of DVT calculated by Rodger and colleagues decrease again with a once-daily LMWH regimen (1)? Can the cost-effectiveness of LMWH observed in patients with DVT be extrapolated to other situations in which LMWH has already been shown to be clinically efficacious, such as unstable angina (2) or pulmonary embolism (3)? In Europe, we have had experience with LMWH for > 15 years. Managing patients with DVT at home is not associated with a higher rate of treatment failure or complications (4). Overuse is possible, however—for example, in patients with "hot red legs" and no accurate diagnosis of DVT or in patients who could reasonably change to oral anticoagulants.
The study gives physicians confirmation of the superiority of LMWH over UFH in terms of efficacy, complication rates, and cost. Patients with uncomplicated DVT should be treated with LMWH at home. The battle is over!
Jean-Francois Bergmann, MD
Hôpital LariboisièreUniversity Paris VIIParis, France
1. Charbonnier BA, Fiessenger JN, Banga JD, et al. Comparison of a once daily with a twice daily subcutaneous low molecular weight heparin regimen in the treatment of deep vein thrombosis. FRADOXI group. Thromb Haemost. 1998;79:897-901.
2. Mark DB, Cowper PA, Berkowitz SD, et al. Economic assessment of low-molecular-weight heparin (enoxaparin) versus unfractionated heparin in acute coronary syndrome patients: results from the ESSENCE randomized trial. Efficacy and Safety of Subcutaneous Enoxaparin in Non-Q wave Coronary Events [unstable angina or non-Q wave myocardial infarction]. Circulation. 1998;97:1702-7.
3. Simonneau G, Sors H, Charbonnier B, et al. A comparison of low-molecular-weight heparin with unfractionated heparin for acute pulmonary embolism. The THESEE Study Group. N Engl J Med. 1997;337:663-9.
4. Koopman MM, Prandoni P, Piovella F, et al. Treatment of venous thromboembolism with intravenous unfractionated heparin administered in the hospital as compared with subcutaneous low-molecular-weight heparin. N Engl J Med. 1996;334:682-7.