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


Economics

Pravastatin cost was £20 375 (U.S. $34 640) per life-year gained for primary prevention among men with increased risk for cardiovascular disease

ACP J Club. 1998 May-June;128:80. doi:10.7326/ACPJC-1998-128-3-080


Source Citation

Caro J, Klittich W, McGuire A, et al. The West of Scotland coronary prevention study: economic benefit analysis of primary prevention with pravastatin. BMJ. 1997 Dec 13;315: 1577-82.


Abstract

Objective

To determine the cost-effectiveness of pravastatin in the prevention of cardiovascular disease in men who have hypercholesterolemia.

Design

An economic model from a government-payer perspective that compared pravastatin with no primary intervention by using data from the West of Scotland Coronary Prevention Study.

Setting

Scotland.

Patients

A theoretical cohort of men (age range 45 to 64 y) who have hypercholesterolemia, no evidence of previous myocardial infarction, and a mean cholesterol level of 7.0 mmol/L.

Intervention

Pravastatin, 40 mg/d, was compared with no primary intervention during the trial. Both groups received dietary advice.

Main cost and outcome measures

The main outcome was the transition from health to cardiovascular disease. The cost per life-year gained was calculated by using the costs of the initial care for each type of cardiovascular event, of giving pravastatin, and of monitoring patients. Only direct costs (1996 British pounds) were used; these were discounted at 6%.

Main results

Over 5 years, cardiovascular disease would be prevented in 318 of 10 000 men who received pravastatin (33 immediate deaths, 138 first nonfatal myocardial infarctions, 68 hospital admissions for angina, 33 revascularizations, and 47 nonfatal strokes or transient ischemic attacks). The discounted cost-effectiveness ratio was £20 375 per life-year gained; the undiscounted cost-effectiveness ratio was £8121. To prevent 1 transition from health to cardiovascular disease, 32 men would need to start treatment. For the 40% of men whose 10-year risk for coronary heart disease was > 20%, 23 men would need to start treatment to prevent 1 transition to cardiovascular disease, and the discounted cost per life-year gained was £13 995 (undiscounted cost per life-year gained was £5601). Sensitivity analyses were used to vary the discount rate; initial risk for cardiovascular disease; costs of the drug, monitoring, and subsequent care; efficacy of prevention; and patient age. The discounted cost-effectiveness ratio was particularly influenced by the estimate of the reduction of risk for cardiovascular disease (£37 788 and £13 419 for a 12% and 33% reduction in risk, respectively) and the cost of the drug. The discounted cost per life-year gained remained < £20 000 for 44% of the combinations tested in sensitivity analyses; it was < £40 000 for 94% of the combinations tested.

Conclusions

In an economic model based on a randomized controlled trial, pravastatin prevented 318 cardiovascular events per 10 000 men. The cost-effectiveness ratio was £20 375 per life-year gained.

Source of funding: In part, Bristol-Myers Squibb.

For article reprint: Dr. J. Caro, Caro Research, 336 Baker Avenue, Concord, MA 01742, USA. FAX 978-371-2445. E-mail jcaro@caroresearch.com.


Commentary

The effectiveness of statins in primary and secondary prevention of coronary heart disease is now well established, but given the size of the potentially treatable population and the purchase price of statins, high-quality evidence on cost-effectiveness has been eagerly awaited. Economic analysis from the Scandinavian Simvastatin Survival Study has provided clear evidence of the cost-effectiveness of simvastatin in secondary prevention (1). However, cost-effectiveness evidence for primary prevention has been scant and unattractive (2, 3), with 1 modeling study estimating an average cost per life-year saved of £136 000 (U.S. $230 000) (2). Now Caro and colleagues have produced cost-effectiveness results derived from the West of Scotland Coronary Prevention Study, which provides better evidence.

The main strength of the analysis is that it is based mainly on outcome and resource data from a large clinical trial and is supplemented by disease-specific survival estimates obtained from a population record-linkage study to predict life-years gained. Costs for follow-up after a coronary event were omitted, and some unit costs seem low, such as £190 ($320) for the first hospital admission for a transient ischemic attack. However, this has a small effect on the results and is likely to result in more conservative estimates.

The overall cost per life-year gained (£20 375 [U.S. $34 640], falling to £13 995 [U.S. $23 790] among the 40% at highest risk) is substantially more favorable and robust than previous estimates. However, the authors' conclusion that the cost “is not prohibitive overall” will depend on the health care system and remains debatable in the United Kingdom National Health Service.

Alastair Gray, DPhil
University of OxfordOxford, England, UK

Alastair Gray, DPhil
University of Oxford
Oxford, England, UK


References

1. Johannesson M, Jönsson B, Kjekshus J, et al. Cost effectiveness of simvastatin treatment to lower cholesterol levels in patients with coronary heart disease. Scandinavian Simvastatin Survival Study Group. N Engl J Med. 1997;336:332-6.

2. Pharoah PD, Hollingworth W. Cost effectiveness of lowering cholesterol concentration with statins in patients with and without pre-existing coronary heart disease: life table method applied to health BMJ. 1996;312:1443-8.

3. Ul Haq I, Ramsay LE, Pickin DM, et al. Lipid-lowering for prevention of coronary heart disease: what policy now? Clin Sci Colch. 1996;91:399-413.