Clinical Questions: What is the cost-effectiveness of pravastatin (Pravachol) treatment for patients at high risk of complications from high cholesterol who are 65 to 74 years of age?
Setting: Outpatient (any)
Study Design: Cost-effectiveness analysis
Synopsis: The Australian researchers conducting this study used data from the Long-term Intervention with Pravastatin in Ischaemic Disease (LIPID) study conducted in the early 1990s to estimate the relative cost of treating high-risk patients with pravastatin to lower their risk of mortality and hospitalization (from the viewpoint of the health care system). The 9,014 patients had a history of a myocardial infarction or unstable angina, had cholesterol levels ranging from 115 to 271 mg per dL (3 to 7 mmol per L), and were randomly assigned to treatment with placebo or pravastatin (40 mg daily) for six years.
This analysis evaluated the cost-effectiveness of the treatment in patients 65 to 74 years of age compared with younger patients. To determine cost, the researchers used actual data on hospitalizations, office visits, diagnostic tests, nursing home stays, and medications (costs were to the Australian health care system). No utilities were used to evaluate outcomes (i.e., effect of treatment on quality of life was not evaluated). The analysis was based on a drop in all-cause mortality from 20.6 to 16.3 percent in older patients and from 9.8 to 7.5 percent in younger patients. This translates into an additional 4.7 to 4.8 months of life in the average patient.
The average cost in American dollars per patient for treatment was $3,693 for older patients and $3,845 for younger patients. These costs were somewhat offset in both groups by decreases in the costs of other medications, hospitalizations, and other costs. The overall additional cost of treatment was lower for older patients ($1,650) compared with younger patients ($2,730). For every 1,000 patients 65 to 74 years of age, pravastatin treatment for six years prevented 43 deaths at a cost of $1.6 million, or $42,767 per life saved. In the younger patient group, 31 deaths were prevented at a cost of $2.7 million, or $128,782 per life saved. These estimates were not adjusted for quality, and the quality of a life saved in the younger group could be better than that of a life saved in the older group. As a result, quality-adjusted life estimates, which take more into account the viewpoint of the patient, could be different from these estimates.
Bottom Line: From the viewpoint of a health care system, it is cost-effective to treat high-risk patients 65 years and older with pravastatin no matter what their initial cholesterol level (more so than for younger patients). The increased cost of treatment is partially offset by savings in other areas. This analysis did not take into account any effect on quality of the life extension by pravastatin. (Level of evidence: 2c)