Current issues of ACP Journal Club are published in Annals of Internal Medicine


Economics

Costs and survival were higher for acute MI treated with t-PA compared with streptokinase

ACP J Club. 1996 Jan-Feb;124:25. doi:10.7326/ACPJC-1996-124-1-025


Source Citation

Mark DB, Hlatky MA, Califf RM, et al. Cost effectiveness of thrombolytic therapy with tissue plasminogen activator as compared with streptokinase for acute myocardial infarction. N Engl J Med. 1995 May 25;332: 1418-24. [PubMed ID: 7723799]


Abstract

Objective

To determine the cost-effectiveness of accelerated tissue plasminogen activator (t-PA) compared with streptokinase in acute myocardial infarction (MI).

Design

Cost-effectiveness analysis using data on mortality and use of resources from the Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries (GUSTO) study and on life expectancy from the Duke Cardiovascular Disease Database.

Setting

1081 hospitals in 15 countries.

Patients

41 021 patients in the GUSTO study provided data for survival. Data on the use of medical resources during the initial hospitalization were provided by the 23 105 U.S. patients, and data on the use of medical resources and quality of life for the 12-month follow-up were provided by a random sample of 2600 U.S. patients.

Intervention

Patients were assigned to t-PA, streptokinase with intravenous heparin, streptokinase with subcutaneous heparin, or t-PA and streptokinase.

Main Cost and Outcome Measures

1-year survival, projected life expectancy beyond 1 year, and incremental cost-effectiveness ratio (expressed as the additional lifetime costs required to add 1 extra year of life with t-PA vs streptokinase therapy). The analysis assumed no additional treatment costs because of t-PA after the first year and projected an increased life expectancy for t-PA of 0.14 years per patient.

Main Results

Survival at 30 days was 92.7% in the streptokinase group and 93.7% in the t-PA group (P = 0.001) and after 1 year was 89.9% and 91.0%, respectively (P = 0.006). With a projected increased life expectancy in the t-PA group of 0.14 years of life per patient, an observed incremental cost of $2845 per patient, and a discount rate of 5%, the comparative primary cost-effectiveness ratio for the use of t-PA instead of streptokinase was $32 678 per year of life saved. The use of t-PA was most cost-effective in older patients and least cost-effective in younger patients. At all ages, the use of t-PA in anterior MIs was more cost-effective than in inferior MIs. The cost-effectiveness values were most sensitive to a lowering of the projected long-term survival benefits of t-PA and to large increases in projected medical visits for patients in the t-PA group after 1 year. The results were not sensitive to additional costs associated with higher rates of disabling stroke in the t-PA group, as noted in the GUSTO study.

Conclusion

The comparative primary cost-effectiveness ratio for the use of tissue plasminogen activator instead of streptokinase was $32 678 per year of life saved.

Sources of funding: Agency for Health Care Policy and Research; Genentech; the National Heart, Lung, and Blood Institute; the Robert Wood Johnson Foundation.

For article reprint: Dr. D.B. Mark, P.O. Box 3485, Duke University Medical Center, Durham, NC 27710, USA. FAX 919-668-7060.


Commentary

The economic effect of a medical service can be measured by its incremental cost-effectiveness (additional cost per additional unit of health outcome) compared with that of conventional medical care. The cost-effectiveness of streptokinase compared with no thrombolytic therapy is as low as $10 000 for definite anterior infarction (1) and generally between $5300 and $21 000 per year of life saved (2). In this study, Mark and colleagues measure the additional cost of using t-PA instead of streptokinase for acute MI. Their conclusion is consistent with the incremental cost-effectiveness of many generally accepted medical services. These results are consistent with the Canadian analysis of Goel and Naylor (3). Assuming that the cost and effect of accelerated t-PA in community practice would be similar to those in the GUSTO protocol, the results imply that t-PA should be used instead of streptokinase.

Mark and colleagues and others (1), however, emphasize that the cost-effectiveness of t-PA depends on the age of the patient and the location of the MI. For example, the cost-effectiveness of t-PA for an inferior MI in a person aged < 40 years would be $203 071 per year of life saved. Also, the lower the probability that a patient is actually having an MI, the worse the cost-effectiveness ratio (1).

The decision to use t-PA, or for that matter streptokinase, depends on whether the resources to obtain these additional outcomes are available, in light of competing demands on the resources. The question of whether the additional cost of t-PA can be justified by its additional effectiveness must be addressed by clinical and health policy decision-makers as they influence practice patterns through guidelines, coverage decisions, and other mechanisms.

John Eisenberg, MD
Georgetown UniversityWashington, DC, USA


References

1. Midgette AS, Wong JB, Beshansky JR, et al. Cost-effectiveness of streptokinase for acute myocardial infarction: a combined meta-analysis and decision analysis of the effects of infarct location and of likelihood of infarction. Med Decis Making. 1994;14:108-17.

2. Goldman L. Cost and quality of life: thrombolysis and primary angioplasty. J Am Coll Cardiol. 1995; 25:38S-41S.

3. Goel V, Naylor CD. Potential cost effectiveness of intravenous tissue plasminogen activator versus streptokinase for acute myocardial infarction. Can J Cardiol. 1992; 8:25-8.