Cost-effectiveness of cholesterol lowering. Results from the Scandinavian Simvastatin Survival Study (4S)

Research trends in contemporary health economics: a scientometric analysis on collective content of specialty journals

INTRODUCTION

Health economics is a thriving sub-discipline of economics. Applied health economics research is considered essential in the health care sector and is used extensively by public policy makers. For scholars, it is important to understand the history and status of health economics-when it emerged, the rate of research output, trending topics, and its temporal evolution-to ensure clarity and direction when formulating research questions.

METHODS

Nearly 13,000 articles were analysed, which were found in the collective publications of the ten most specialised health economic journals. We explored this literature using patterns of term co-occurrence and document co-citation.

RESULTS

The research output in this field is growing exponentially. Five main research divisions were identified: (i) macroeconomic evaluation, (ii) microeconomic evaluation, (iii) measurement and valuation of outcomes, (iv) monitoring mechanisms (evaluation), and (v) guidance and appraisal. Document co-citation analysis revealed eighteen major research streams and identified variation in the magnitude of activities in each of the streams. A recent emergence of research activities in health economics was seen in the Medicaid Expansion stream. Established research streams that continue to show high levels of activity include Child Health, Health-related Quality of Life (HRQoL) and Cost-effectiveness. Conversely, Patient Preference, Health Care Expenditure and Economic Evaluation are now past their peak of activity in specialised health economic journals. Analysis also identified several streams that emerged in the past but are no longer active.

CONCLUSIONS

Health economics is a growing field, yet there is minimal evidence of creation of new research trends. Over the past 10 years, the average rate of annual increase in internationally collaborated publications is almost double that of domestic collaborations (8.4% vs 4.9%), but most of the top scholarly collaborations remain between six countries only.

HMG CoA reductase inhibitors (statins) for people with chronic kidney disease not requiring dialysis

BACKGROUND

Cardiovascular disease is the most frequent cause of death in people with early stages of chronic kidney disease (CKD), and the absolute risk of cardiovascular events is similar to people with coronary artery disease. This is an update of a review first published in 2009 and updated in 2014, which included 50 studies (45,285 participants).

OBJECTIVES

To evaluate the benefits and harms of statins compared with placebo, no treatment, standard care or another statin in adults with CKD not requiring dialysis.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies up to 4 October 2023. Studies in the Register are identified through searches of CENTRAL, MEDLINE, EMBASE, conference proceedings, the International Clinical Trials Registry Platform (ICTRP) Search Portal and ClinicalTrials.gov. An updated search will be undertaken every three months.

SELECTION CRITERIA

Randomised controlled trials (RCTs) and quasi-RCTs that compared the effects of statins with placebo, no treatment, standard care, or other statins, on death, cardiovascular events, kidney function, toxicity, and lipid levels in adults with CKD (estimated glomerular filtration rate (eGFR) 90 to 15 mL/min/1.73 m2) were included.

DATA COLLECTION AND ANALYSIS

Two or more authors independently extracted data and assessed the study risk of bias. Treatment effects were expressed as mean difference (MD) for continuous outcomes and risk ratios (RR) for dichotomous benefits and harms with 95% confidence intervals (CI). The risk of bias was assessed using the Cochrane risk of bias tool, and the certainty of the evidence using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

MAIN RESULTS

We included 63 studies (50,725 randomised participants); of these, 53 studies (42,752 participants) compared statins with placebo or no treatment. The median duration of follow-up was 12 months (range 2 to 64.8 months), the median dosage of statin was equivalent to 20 mg/day of simvastatin, and participants had a median eGFR of 55 mL/min/1.73 m2. Ten studies (7973 participants) compared two different statin regimens. We were able to meta-analyse 43 studies (41,273 participants). Most studies had limited reporting and hence exhibited unclear risk of bias in most domains. Compared with placebo or standard of care, statins prevent major cardiovascular events (14 studies, 36,156 participants: RR 0.72, 95% CI 0.66 to 0.79; I2 = 39%; high certainty evidence), death (13 studies, 34,978 participants: RR 0.83, 95% CI 0.73 to 0.96; I² = 53%; high certainty evidence), cardiovascular death (8 studies, 19,112 participants: RR 0.77, 95% CI 0.69 to 0.87; I² = 0%; high certainty evidence) and myocardial infarction (10 studies, 9475 participants: RR 0.55, 95% CI 0.42 to 0.73; I² = 0%; moderate certainty evidence). There were too few events to determine if statins made a difference in hospitalisation due to heart failure. Statins probably make little or no difference to stroke (7 studies, 9115 participants: RR 0.64, 95% CI 0.37 to 1.08; I² = 39%; moderate certainty evidence) and kidney failure (3 studies, 6704 participants: RR 0.98, 95% CI 0.91 to 1.05; I² = 0%; moderate certainty evidence) in people with CKD not requiring dialysis. Potential harms from statins were limited by a lack of systematic reporting. Statins compared to placebo may have little or no effect on elevated liver enzymes (7 studies, 7991 participants: RR 0.76, 95% CI 0.39 to 1.50; I² = 0%; low certainty evidence), withdrawal due to adverse events (13 studies, 4219 participants: RR 1.16, 95% CI 0.84 to 1.60; I² = 37%; low certainty evidence), and cancer (2 studies, 5581 participants: RR 1.03, 95% CI 0.82 to 1.30; I² = 0%; low certainty evidence). However, few studies reported rhabdomyolysis or elevated creatinine kinase; hence, we are unable to determine the effect due to very low certainty evidence. Statins reduce the risk of death, major cardiovascular events, and myocardial infarction in people with CKD who did not have cardiovascular disease at baseline (primary prevention). There was insufficient data to determine the benefits and harms of the type of statin therapy.

AUTHORS' CONCLUSIONS

Statins reduce death and major cardiovascular events by about 20% and probably make no difference to stroke or kidney failure in people with CKD not requiring dialysis. However, due to limited reporting, the effect of statins on elevated creatinine kinase or rhabdomyolysis is unclear. Statins have an important role in the primary prevention of cardiovascular events and death in people who have CKD and do not require dialysis. Editorial note: This is a living systematic review. We will search for new evidence every three months and update the review when we identify relevant new evidence. Please refer to the Cochrane Database of Systematic Reviews for the current status of this review.

Quality of health economic evaluations for the ACC/AHA stable ischemic heart disease practice guideline: A systematic review

BACKGROUND

The American College of Cardiology/American Heart Association (ACC/AHA) recently published a rigorous framework to guide integration of economic data into clinical guidelines. We assessed the quality of economic evaluations in a major ACC/AHA clinical guidance report.

METHODS

We systematically identified cost-effectiveness analyses (CEAs) of RCTs cited in the ACC/AHA 2012 Guideline for the Diagnosis and Management of Patients with Stable Ischemic Heart Disease. We extracted: (1) study identifiers; (2) parent RCT information; (3) economic analysis characteristics; and (4) study quality using the Quality of Health Economic Studies instrument (QHES).

RESULTS

Quality scores were categorized as high (≥75 points) or low (<75 points). Of 1,266 citations in the guideline, 219 were RCTs associated with 77 CEAs. Mean quality score was 81 (out of 100) and improved over time, though 29.9% of studies were low-quality. Cost-per-QALY was the most commonly reported primary outcome (39.0%). Low-quality studies were less likely to report study perspective, use appropriate time horizons, or address statistical and clinical uncertainty. Funding was overwhelmingly private (83%). A detailed methodological assessment of high-quality studies revealed domains of additional methodological issues not identified by the QHES.

CONCLUSIONS

Economic evaluations of RCTs in the 2012 ACC/AHA ischemic heart disease guideline largely had high QHES scores but methodological issues existed among "high-quality" studies. Because the ACC/AHA has generally been more systematic in its integration of scientific evidence compared to other professional societies, it is likely that most societies will need to proceed more cautiously in their integration of economic evidence.

Cost-Effectiveness of Atorvastatin for the Prevention of Coronary and Stroke Events: An Economic Analysis of the Anglo-Scandinavian Cardiac Outcomes Trial—Lipid-Lowering Arm (ASCOT-LLA)

Background

The aim of this study is to assess the cost-effectiveness of the lipid-lowering arm of the Anglo-Scandinavian Cardiac Outcomes Trial (ASCOT-LLA) where patients from seven countries with hypertension and no history of coronary heart disease (CHD) were randomized to receive 10 mg atorvastatin or placebo.

Design

Economic analysis of a randomized controlled trial.

Methods

Data on resource use were aggregated for all patients during the entire trial period (median 3.3 years) and multiplied with unit costs for Sweden and the UK. The total number of cardiovascular events and procedures avoided was used as the measure of effectiveness.

Results

Patients treated with atorvastatin had an additional net costs of 449 ϵ (4114 SEK) in Sweden and 414 ϵ (£260) in the UK, but fewer events per patient (0.097 compared to 0.132). The incremental cost-effectiveness ratios were 12673 ϵ (116119 SEK) and 11693 ϵ (£7349) per event avoided.

Conclusion

Based on comparisons with the WOSCOPS and 4S studies, atorvastatin at 10 mg to treat patients as in the ASCOT study, appears to be a cost-effective strategy. Eur J Cardiovasc Prev Rehabil 12:29-36 © 2005 The European Society of Cardiology

Rosuvastatin is Cost-Effective in Treating Patients to Low-Density Lipoprotein-Cholesterol Goals Compared with Atorvastatin, Pravastatin and Simvastatin: Analysis of the Stellar Trial

Background

Rosuvastatin calcium (CRESTOR®) has demonstrated superior efficacy in reducing low-density lipoprotein cholesterol (LDL-C). However, healthcare providers and authorities require information on its cost-effectiveness in the treatment of dyslipidaemia.

Design

A retrospective pharmacoeconomic analysis was performed using data from the Statin Therapies for Elevated Lipid Levels compared Across doses to Rosuvastatin (STELLAR) trial. The cost-effectiveness of rosuvastatin 10-40 mg was compared with atorvastatin 10-80 mg, pravastatin 10-40 mg and both branded and generic simvastatin 10-80 mg in achieving Third Joint European Task Force LDL-C goals in patients with hypercholesterolaemia.

Methods

The analysis was conducted from the perspective of the UK National Health Service, using clinical data from the STELLAR trial and drug acquisition costs. Cost-effectiveness was compared using incremental cost-effectiveness ratios (ICERs), with sensitivity analyses applied to both efficacy and cost parameters.

Results

In terms of patients achieving goal, rosuvastatin 10 mg dominated (was more effective at equal or lower cost) atorvastatin 10 and 20 mg, pravastatin 20 and 40 mg, branded simvastatin 10-80 mg and generic simvastatin 40 and 80 mg. Where rosuvastatin 10 mg did not dominate, ICERs ranged from £36 to £162 per extra patient to goal. Rosuvastatin 20 and 40 mg were cost-effective compared with milligram-equivalent and higher doses of other branded statins. Sensitivity analyses showed that the results were robust to variations in both statin efficacy and price.

Conclusion

In patients with hypercholesterolaemia, rosuvastatin is a cost-effective statin option in treating to LDL-C goals. Eur J Cardiovasc Prev Rehabil 12:18-28 © 2005 The European Society of Cardiology

A Systematic Review of Cardiovascular Outcomes-Based Cost-Effectiveness Analyses of Lipid-Lowering Therapies

BACKGROUND

Previous reviews have evaluated economic analyses of lipid-lowering therapies using lipid levels as surrogate markers for cardiovascular disease. However, drug approval and health technology assessment agencies have stressed that surrogates should only be used in the absence of clinical endpoints.

OBJECTIVE

The aim of this systematic review was to identify and summarise the methodologies, weaknesses and strengths of economic models based on atherosclerotic cardiovascular disease event rates.

METHODS

Cost-effectiveness evaluations of lipid-lowering therapies using cardiovascular event rates in adults with hyperlipidaemia were sought in Medline, Embase, Medline In-Process, PubMed and NHS EED and conference proceedings. Search results were independently screened, extracted and quality checked by two reviewers.

RESULTS

Searches until February 2016 retrieved 3443 records, from which 26 studies (29 publications) were selected. Twenty-two studies evaluated secondary prevention (four also assessed primary prevention), two considered only primary prevention and two included mixed primary and secondary prevention populations. Most studies (18) based treatment-effect estimates on single trials, although more recent evaluations deployed meta-analyses (5/10 over the last 10 years). Markov models (14 studies) were most commonly used and only one study employed discrete event simulation. Models varied particularly in terms of health states and treatment-effect duration. No studies used a systematic review to obtain utilities. Most studies took a healthcare perspective (21/26) and sourced resource use from key trials instead of local data. Overall, reporting quality was suboptimal.

CONCLUSIONS

This review reveals methodological changes over time, but reporting weaknesses remain, particularly with respect to transparency of model reporting.

HMG CoA reductase inhibitors (statins) for people with chronic kidney disease not requiring dialysis

BACKGROUND

Cardiovascular disease (CVD) is the most frequent cause of death in people with early stages of chronic kidney disease (CKD), for whom the absolute risk of cardiovascular events is similar to people who have existing coronary artery disease. This is an update of a review published in 2009, and includes evidence from 27 new studies (25,068 participants) in addition to the 26 studies (20,324 participants) assessed previously; and excludes three previously included studies (107 participants). This updated review includes 50 studies (45,285 participants); of these 38 (37,274 participants) were meta-analysed.

OBJECTIVES

To evaluate the benefits (such as reductions in all-cause and cardiovascular mortality, major cardiovascular events, MI and stroke; and slow progression of CKD to end-stage kidney disease (ESKD)) and harms (muscle and liver dysfunction, withdrawal, and cancer) of statins compared with placebo, no treatment, standard care or another statin in adults with CKD who were not on dialysis.

SEARCH METHODS

We searched the Cochrane Renal Group's Specialised Register to 5 June 2012 through contact with the Trials' Search Co-ordinator using search terms relevant to this review.

SELECTION CRITERIA

Randomised controlled trials (RCTs) and quasi-RCTs that compared the effects of statins with placebo, no treatment, standard care, or other statins, on mortality, cardiovascular events, kidney function, toxicity, and lipid levels in adults with CKD not on dialysis were the focus of our literature searches.

DATA COLLECTION AND ANALYSIS

Two or more authors independently extracted data and assessed study risk of bias. Treatment effects were expressed as mean difference (MD) for continuous outcomes (lipids, creatinine clearance and proteinuria) and risk ratio (RR) for dichotomous outcomes (major cardiovascular events, all-cause mortality, cardiovascular mortality, fatal or non-fatal myocardial infarction (MI), fatal or non-fatal stroke, ESKD, elevated liver enzymes, rhabdomyolysis, cancer and withdrawal rates) with 95% confidence intervals (CI).

MAIN RESULTS

We included 50 studies (45,285 participants): 47 studies (39,820 participants) compared statins with placebo or no treatment and three studies (5547 participants) compared two different statin regimens in adults with CKD who were not yet on dialysis. We were able to meta-analyse 38 studies (37,274 participants).The risk of bias in the included studies was high. Seven studies comparing statins with placebo or no treatment had lower risk of bias overall; and were conducted according to published protocols, outcomes were adjudicated by a committee, specified outcomes were reported, and analyses were conducted using intention-to-treat methods. In placebo or no treatment controlled studies, adverse events were reported in 32 studies (68%) and systematically evaluated in 16 studies (34%).Compared with placebo, statin therapy consistently prevented major cardiovascular events (13 studies, 36,033 participants; RR 0.72, 95% CI 0.66 to 0.79), all-cause mortality (10 studies, 28,276 participants; RR 0.79, 95% CI 0.69 to 0.91), cardiovascular death (7 studies, 19,059 participants; RR 0.77, 95% CI 0.69 to 0.87) and MI (8 studies, 9018 participants; RR 0.55, 95% CI 0.42 to 0.72). Statins had uncertain effects on stroke (5 studies, 8658 participants; RR 0.62, 95% CI 0.35 to 1.12).Potential harms from statin therapy were limited by lack of systematic reporting and were uncertain in analyses that had few events: elevated creatine kinase (7 studies, 4514 participants; RR 0.84, 95% CI 0.20 to 3.48), liver function abnormalities (7 studies, RR 0.76, 95% CI 0.39 to 1.50), withdrawal due to adverse events (13 studies, 4219 participants; RR 1.16, 95% CI 0.84 to 1.60), and cancer (2 studies, 5581 participants; RR 1.03, 95% CI 0.82 to 130).Statins had uncertain effects on progression of CKD. Data for relative effects of intensive cholesterol lowering in people with early stages of kidney disease were sparse. Statins clearly reduced risks of death, major cardiovascular events, and MI in people with CKD who did not have CVD at baseline (primary prevention).

AUTHORS' CONCLUSIONS

Statins consistently lower death and major cardiovascular events by 20% in people with CKD not requiring dialysis. Statin-related effects on stroke and kidney function were found to be uncertain and adverse effects of treatment are incompletely understood. Statins have an important role in primary prevention of cardiovascular events and mortality in people who have CKD.

Economic Evaluation of Lipid-Lowering Therapy in the Secondary Prevention Setting in the Philippines

OBJECTIVE

To determine the cost-effectiveness of lipid-lowering therapy in the secondary prevention of cardiovascular events in the Philippines.

METHODS

A cost-utility analysis was performed by using Markov modeling in the secondary prevention setting. The models incorporated efficacy of lipid-lowering therapy demonstrated in randomized controlled trials and mortality rates obtained from local life tables. Average and incremental cost-effectiveness ratios were obtained for simvastatin, atorvastatin, pravastatin, and gemfibrozil. The costs of the following were included: medications, laboratory examinations, consultation and related expenses, and production losses. The costs were expressed in current or nominal prices as of the first quarter of 2010 (Philippine peso). Utility was expressed in quality-adjusted life-years gained. Sensitivity analyses were performed by using variations in the cost centers, discount rates, starting age, and differences in utility weights for stroke.

RESULTS

In the analysis using the lower-priced generic counterparts, therapy using 40 mg simvastatin daily was the most cost-effective option compared with the other therapies, while pravastatin 40 mg daily was the most cost-effective alternative if the higher-priced innovator drugs were used. In all sensitivity analyses, gemfibrozil was strongly dominated by the statins.

CONCLUSIONS

In secondary prevention, simvastatin or pravastatin were the most cost-effective options compared with atorvastatin and gemfibrozil in the Philippines. Gemfibrozil was strongly dominated by the statins.

Cost-effectiveness of statins revisited: lessons learned about the value of innovation

BACKGROUND

The economic evaluation of statins has undergone a development from risk-factor-based models to modeling of hard end points in clinical trials with a shift back to risk-factor models after increased confidence in their predictive power has now been established. At this point, we can look back on the historical economic data on simvastatin to see what lesson regarding reimbursement we can learn.

METHODS

Historical data on the usage and sales of simvastatin in Sweden were combined with published epidemiological and clinical data to calculate the social value of simvastatin to the present day and to make projection until projected until 2018. The distribution of the social surplus was calculated by taking the costs born by society and the producer of the drug into consideration.

RESULTS

The cost of simvastatin fell drastically following patent expiration, although the number of treated patients has continued to grow. Presently, the use of simvastatin is close to cost neutrality taking direct and indirect cost savings from reduced morbidity into account. However, the major part of the social surplus generated comes from the value of improved quality-adjusted survival. Of the social surplus generated, the producer appropriated 20-43% of the value during the on-patent period, a figure dropping to 1% following loss of exclusivity. The total producer surplus between 1987 and 2018 is 2-5% of the total social surplus.

CONCLUSION

Only a small part of the surplus value generated was appropriated by the producer. A regulatory and reimbursement approach that favors early market access and coverage with evidence development as opposed to long-term trials as a pre-requisite for launch is more attractive from both a company and social perspective.

Medication therapy management and condition care services in a community-based employer setting

PURPOSE

A program in which health-system pharmacists and pharmacy technicians provide medication therapy management (MTM), wellness, and condition care (disease management) services under contract with local businesses is described.

SUMMARY

The health-system pharmacy department's Center for Medication Management contracts directly with company benefits departments for defined services to participating employees. The services include an initial wellness and MTM session and, for certain patients identified during the initial session, ongoing condition care. The initial appointment includes a medication history, point-of-care testing for serum lipids and glucose, body composition analysis, and completion of a health risk assessment. The pharmacist conducts a structured MTM session, reviews the patient's test results and risk factors, provides health education, discusses opportunities for cost savings, and documents all activities on the patient's medication action plan. Eligibility for the condition care program is based on a diagnosis of diabetes, hypertension, asthma, heart failure, or hyperlipidemia or elevation of lipid or glucose levels. Findings are summarized for employers after the initial wellness screening and at six-month intervals. Patients receiving condition care sign a customized contract, establish goals, attend up to four MTM sessions per year, and track their information on a website; employers may offer incentives for participation. When pharmacists recommend adjustments to therapy or cost-saving changes, it is up to patients to discuss these with their physician. A survey completed by each patient after the initial wellness session has indicated high satisfaction. Direct cost savings related to medication changes have averaged $253 per patient per year. Total cost savings to companies in the first year of the program averaged $1011 per patient. For the health system, the program has been financially sustainable. Key laboratory values indicate positive clinical outcomes.

CONCLUSION

A business model in which health-system pharmacists provide MTM and condition care services for company employees has demonstrated successful outcomes in terms of patient satisfaction, cost savings, and clinical benefits.

Costs and consequences of clopidogrel versus aspirin for secondary prevention of ischaemic events in (high-risk) atherosclerotic patients in Sweden: a lifetime model based on the CAPRIE trial and high-risk CAPRIE subpopulations

BACKGROUND

Antiplatelet therapy plays a central role in the prevention of atherothrombotic events. Both acetylsalicylic acid (aspirin) and clopidogrel have been shown to reduce the risk of recurrent cardiovascular events in various subgroups of patients with vascular disease.

OBJECTIVE

To estimate the cost effectiveness of clopidogrel versus aspirin in Sweden for the prevention of atherothrombotic events based on CAPRIE trial data. The focus of this study is on two high-risk subpopulations: (i) patients with pre-existing symptomatic atherosclerotic disease; and (ii) patients with polyvascular disease.

METHODS

A Markov model combining clinical, epidemiological and cost data was used to assess the economic value of clopidogrel compared with aspirin during a patient's lifetime. A societal perspective was used, with costs stated in Swedish kronor (SEK), year 2007 values. For the first 2 years, the clinical input for the model was based on the relevant subpopulations in the CAPRIE trial. Thereafter, transition probabilities were extrapolated, taking account of increased risks related to age and to a history of events. Cost effectiveness of 2 years of therapy is presented as cost per life-year gained (LYG) and as cost per QALY. Univariate and multivariate sensitivity analyses were performed to investigate robustness of results.

RESULTS

For patients resembling the total CAPRIE population, who were treated with clopidogrel, the expected cost per LYG was SEK217,806 and the cost per QALY was estimated at SEK169,154. For the high-risk CAPRIE subpopulations, costs per QALY were lowest for patients with pre-existing symptomatic atherosclerotic disease (SEK38,153). Using a 'willingness-to-pay' perspective indicated that treatment with clopidogrel instead of aspirin in high-risk patients is associated with a high probability for cost effectiveness; 81% using a threshold of SEK100,000 per QALY and 98% using a threshold of SEK500,000 per QALY. Overall, the results appeared to be robust over the sensitivity analyses performed.

CONCLUSION

When considering the cost-effectiveness categorization as proposed by the Swedish National Board of Health and Welfare, clopidogrel appears to be associated with costs per QALY that range from intermediate in the total CAPRIE population to low in high-risk atherosclerotic patients.

Cost-effectiveness of intensive atorvastatin therapy in secondary cardiovascular prevention in the United Kingdom, Spain, and Germany, based on the Treating to New Targets study

The Treating to New Targets (TNT) clinical trial found that intensive 80 mg atorvastatin (A80) treatment reduced cardiovascular events by 22% when compared to 10 mg atorvastatin (A10) treatment. We evaluated the cost-effectiveness of intensive A80 vs A10 treatment in the United Kingdom (UK), Spain, and Germany. A lifetime Markov model was developed to predict cardiovascular disease-related events, costs, survival, and quality-adjusted life-years (QALYs). Treatment-specific event probabilities were estimated from the TNT clinical trial. Post-event survival, health-related quality of life, and country-specific medical-care costs were estimated using published sources. Intensive treatment with A80 increased both the per-patient QALYs and corresponding costs of care, when compared to the A10 treatment, in all three countries. The incremental cost per QALY gained was <euro> 9,500, <euro> 21,000, and <euro> 15,000 in the UK, Spain, and Germany, respectively. Intensive A80 treatment is estimated to be cost-effective when compared to A10 treatment in secondary cardiovascular prevention.

An economic evaluation of a perindopril-based blood pressure lowering regimen for patients who have suffered a cerebrovascular event

OBJECTIVES

Cerebrovascular disease (or stroke) is one of the main causes of long-term disability and the second leading cause of death worldwide. The economic impact of stroke is clearly seen, as it is the largest single cause of bed occupancy in hospitals in England and accounts for 6% of hospital costs. This analysis is the first to quantify the economic consequences of a blood pressure lowering regimen based on the PROGRESS study (perindopril-based regimen), for reducing future cardiovascular events.

DESIGN

A Markov decision analytical model was used to estimate the cost per quality adjusted life year (QALY) of blood pressure lowering in the treatment of patients presenting with a cerebrovascular event. The health states are based upon Barthel indices for which resource utilisation and health benefits have previously been estimated.

SETTING

The participants for the economic analysis were obtained from the PROGRESS study database. 6,105 clinical study participants were recruited through both primary and secondary care centres.

PARTICIPANTS

The mean age was 64 years; 70% were male in the original study.

INTERVENTIONS

In the PROGRESS study, blood pressure lowering by a perindopril-based regimen was compared to standard care.

MAIN OUTCOME MEASURES

Cost per quality adjusted life year for the duration of the study (4 years) and for a time span of 20 years.

RESULTS

Using only direct hospital medical costs, the cost per QALY for a perindopril based regimen is pound 6,927 for the base study period and pound 10,133 for a 20-year time period. These results are sensitive to the cost of perindopril, the cost of the stroke unit, length of stay, and to a lesser extent, the cost of indapamide.

CONCLUSIONS

This analysis demonstrates a cost-effective treatment for patients suffering a cerebrovascular event with a blood pressure lowering regimen. The findings of this study are in line with current decisions and guidance by the national institute for health and clinical excellence (NICE) in England.

Economic evaluations of cholesterol-lowering drugs: a critical and systematic review

The wide availability of economic evaluations and their increasing importance for decision making emphasises the need for economic evaluations that are methodologically sound. The aim of this review was to provide users of economic evaluations of cholesterol-lowering drugs with an insight into the quality of these evaluations. By focusing on the most relevant studies, the gap between research and policy making may be narrowed. A systematic review was conducted. All Dutch and English publications on economic evaluations of cholesterol-lowering drugs were identified by searching PubMed, the Centre for Reviews and Dissemination database (CRD), the NHS Economic Evaluation Database (NHS EED), the Health Technology Assessment database (HTA) and the Database of Abstracts of Reviews of Effects (DARE). A search strategy was set up to identify the articles to be included. The quality of these articles was assessed using Drummond's checklists. The scoring was performed by at least two reviewers. When necessary, disagreement between these reviewers was decided upon in a consensus meeting. We calculated an average quality score for the included articles. The search identified 1390 articles, of which 23 were included. Most studies measured the costs per life-year gained. The overall score per study was disappointing and varied between 2.7 and 7.7, with an average of 5.5. Most studies scored high on the measurement of costs and consequences, whereas the establishment of effectiveness left room for improvement. Only two studies included a well performed incremental analysis. This study noted an increase of quality of economic evaluations over time, suggesting the value of cost-effectiveness studies for policy decisions increases over time. In general, piggy-back evaluations tended to score higher on quality and may therefore be more valuable in decision making.

Effectiveness calculation in economic analysis: the case of statins for cardiovascular disease prevention

OBJECTIVES

This report aimed to evaluate the calculation of estimates of effectiveness in cost effectiveness analyses of statins for cardiovascular disease prevention.

METHODS

Methodological aspects were reviewed of seven primary studies (based on trial results) and 12 secondary modelling studies (extrapolated) on the cost effectiveness of statin treatment, published between 1995 and 2002. Estimates of life years gained were extracted and compared with estimates calculated using the Dutch male life table of 1996-2000.

RESULTS

Of the seven primary modelling analyses, six showed all the essential data. They estimated that 3 to 5.6 years (average 4.6 years) of statin treatment resulted in 0.15 to 0.41 years (average 0.3 years) saved over a lifetime time horizon. In contrast none of the 12 secondary modelling studies provided transparent results. They assumed lifelong treatment, leading to life table estimations of 2.4 and 2.0 (undiscounted) years saved for 40 and 60 year olds, with peak savings at around the mean age of death: 75-80 years. With 5% discounting, these effects reduced to 0.4 and 0.8 years respectively.

CONCLUSION

Reporting of essential data and assumptions on statin treatment was poor for secondary modelling analyses and satisfactory for primary modelling studies. Secondary modeling studies made assumptions on long term effectiveness that were hard to justify with the available evidence, and that led to the majority of life years saved at high ages. Further standardisation in economic analyses is important to guarantee transparency and reproducibility of results.

Analytic considerations in economic evaluations of multinational cardiovascular clinical trials

OBJECTIVES

The growing number of economic evaluations that use data collected in multinational clinical trials raises numerous questions regarding their execution and interpretation. Although recommendations for conducting economic evaluations have been widely disseminated, relatively little guidance has been given for conducting economic evaluations alongside clinical trials, particularly multinational trials.

METHODS

Building on a literature review that was conducted in preparation for an expert workshop, we evaluated a subset of methodological issues related to conducting economic evaluations alongside multinational clinical trials.

RESULTS

We found wide variation in the types of costs included as part of the analyses and in the methods used to assign costs to hospitalization events. Furthermore, we found that the extrapolation of costs and survival outcomes beyond the trial period is an inconsistent practice and is often not dependent on whether a survival benefit was observed in the trial or on the epidemiology or practice patterns in the country to which the findings are directed.

CONCLUSIONS

Although the limited sample size precluded a quantitative analysis of trial characteristics and their associations with the methodologies employed, our findings highlight the need for more guidance to analysts regarding the execution of economic evaluations using data from multinational clinical trials. As the research community grapples with the complexities of methodological and logistical issues involved in multinational economic evaluations, the development of a standardized format to report the basic methodological characteristics of such studies would help to improve transparency and comparability for other analysts and decision-makers.

Cost effectiveness of statins in coronary heart disease

INTRODUCTION

Statin therapy reduces the rate of coronary heart disease, but high costs in combination with a large population eligible for treatment ask for priority setting. Although trials agree on the size of the benefit, economic analyses of statins report contradictory results. This article reviewed cost effectiveness analyses of statins and sought to synthesise cost effectiveness ratios for categories of risk of coronary heart disease and age.

METHODS

The review searched for studies comparing statins with no treatment for the prevention of either cardiovascular or coronary heart disease in men and presenting cost per years of life saved as outcome. Estimates were extracted, standardised for calendar year and currency, and stratified by categories of risk, age, and funding source

RESULTS

24 studies were included (from 50 retrieved), yielding 216 cost effectiveness ratios. Estimated ratios increase with decreasing risk. After stratification by risk, heterogeneity of ratios is large varying from savings to $59 000 per life year saved in the highest risk category and from 6500 dollars to 490,000 dollars in the lowest category. The pooled estimates show values of 21571 dollars per life year saved for a 10 year coronary heart disease risk of 20% and 16862 dollars per life year saved for 10 year risk of 30%.

CONCLUSION

Statin therapy is cost effective for high levels of risk, but inconsistencies exist at lower levels. Although the cost effectiveness of statins depends mainly on absolute risk, important heterogeneity remains after adjusting for absolute risk. Economic analyses need to increase their transparency to reduce their vulnerability to bias and increase their reproducibility.

Cost effectiveness of adding ezetimibe to atorvastatin therapy in patients not at cholesterol treatment goal in Canada

INTRODUCTION

This analysis compared the cost effectiveness of adding ezetimibe to atorvastatin therapy versus atorvastatin titration or adding cholestyramine (a resin) for patients at high risk of a coronary artery disease (CAD) event who did not reach target cholesterol levels on their current atorvastatin dosage. The primary analysis focused on 65-year-old patients with low-density lipoprotein cholesterol (LDL-C) levels of 3.1 or 3.6 mmol/L with a treatment goal of <2.5 mmol/L, classified as very high risk according to the 2000 Canadian Guidelines for Management and Treatment of Hyperlipidaemia.

METHODS

A previously developed Markov model was utilised to capture the cost and clinical consequences of lipid-lowering therapy in primary and secondary prevention of CAD. Comparisons between treatment strategies were made using ICERs (cost per QALY) from a Canadian Ministry of Health perspective. The effects of lipid-lowering therapies were based on clinical trial data. The risks of CAD events were estimated using Framingham Heart Study risk equations. Treatment costs and the costs of acute and long-term care for CAD events were included in the analysis. Costs (Canadian dollar, 2002 values) and outcomes were discounted at 5% per annum.

RESULTS

Ezetimibe added to atorvastatin therapy compared with treatment with the most common fixed atorvastatin daily dosage (10 mg) or with common atorvastatin titration strategies (up to 20 mg daily; up to 40 mg daily) resulted in cost per QALY estimates ranging from 25,344 to 44,332 Canadian dollars. The addition of ezetimibe to atorvastatin therapy was less costly and more effective than the addition of cholestyramine (dominant).

CONCLUSION

Our analysis suggests that adding ezetimibe to atorvastatin for patients not achieving treatment goals with their current atorvastatin dose produces greater clinical benefits than treatment with a fixed-dose atorvastatin or atorvastatin titration at an increased overall cost. The cost-effectiveness ratios provide strong evidence for the adoption of ezetimibe within the Canadian healthcare system.

Can economic evaluations be made more transferable?

Several commentators have identified the lack of generalisability and transferability of economic evaluation results. The aims of this study were: (a) to develop a checklist to assess the level of generalisability and transferability of economic evaluations; (b) to assess the generalisability and transferability of economic evaluations between the UK and France using the checklist; (c) to identify reasons for any lack of transferability and generalisability; (d) to assess how the transferability and generalisability of economic evaluations can be improved; and (e) to outline ways in which databases of economic evaluations and journals can assist in this area. The checklist was developed using previous work and the templates of the NHS EED and CODECS databases. A sub-checklist of essential items was then derived. Validation of the two checklists was undertaken with Health Economists participating in the EURONHEED project. Economic evaluations involving the UK and France were then located and assessed using the checklist. A summary score for each study was calculated based on the percentage of correctly reported (applicable) points, and the results in the empirical analysis compared to identify differences. The extended checklist includes 42 items, and the sub-checklist 16 items. Twenty-five economic evaluations met the inclusion criteria for the empirical analysis. In the extended checklist the mean score was 66.9+/-13.6%. The results for the sub-checklist were very similar. The analysis revealed that costing, assessments of generalisability by the author(s), assessment of data variability, discounting, study population, and the reporting of effectiveness are areas that need more attention. Differences in cost-effectiveness results are often accounted for by price or organisational differences. The developed checklists are useful in assessing the generalisability and transferability of economic evaluations. In order to improve the generalisability and transferability of economic evaluations authors need to be more explicit and detailed in describing and reporting their studies. If they are to provide added value to their users, international databases of economic evaluations should systematically assess the generalisability and transferability of studies. Further research is in progress on producing a weighted version of the checklist.

Long-Term Cost Effectiveness of Early and Sustained Dual Oral Antiplatelet Therapy With Clopidogrel Given for Up to One Year After Percutaneous Coronary Intervention

OBJECTIVES

This study sought to evaluate the long-term cost effectiveness of a clopidogrel loading strategy before percutaneous coronary intervention (PCI) followed by continued treatment for one year.

BACKGROUND

The Clopidogrel for the Reduction of Events During Observation (CREDO) trial, a randomized trial of 2,116 patients, showed the effectiveness of antiplatelet therapy with clopidogrel 300 mg before PCI and 75 mg daily for one year afterward compared with placebo load and placebo days 29 to 365 in reducing the combined risk of death, myocardial infarction, and stroke. All patients received clopidogrel on days 1 to 28 and aspirin on days 1 to 365.

METHODS

All hospitalizations were assigned a diagnosis-related group. Associated costs were estimated three ways (including professional costs): 1) Medicare costs, 2) MEDSTAT costs, and 3) blend with Medicare for those age > or = 65 years and MEDSTAT for those age <65 years. Clopidogrel 75 mg cost 3.22 dollars. Life expectancy in trial survivors was estimated using external data. Confidence intervals were assessed by bootstrap.

RESULTS

The primary composite end point occurred in 89 (8.45%) clopidogrel patients and in 122 (11.48%) placebo patients (relative risk reduction [RRR] 26.9%; 95% confidence interval [CI] 3.9% to 44.4%). The number of life-years gained (LYG) with clopidogrel was 0.1526 (95% CI 0.0263 to 0.2838) using Framingham data and 0.1920 (95% CI 0.054 to 0.337) using Saskatchewan data. Average total costs were 664 dollars higher for the clopidogrel arm (95% CI -461 dollars to 1,784 dollars). The incremental cost-effectiveness ratios (ICERs) based on Framingham data ranged from 3,685 dollars/LYG to 4,353 dollars/LYG, with over 97% of bootstrap-derived ICER estimates below 50,000 dollars/LYG. The ICERs based on Saskatchewan data were 2,929 dollars/LYG to 3,460 dollars/LYG, with over 98% of estimates below 50,000 dollars/LYG.

CONCLUSIONS

Platelet inhibition with clopidogrel loading before PCI followed by therapy for one year is highly cost effective.

Cost-effectiveness of simvastatin in people at different levels of vascular disease risk: economic analysis of a randomised trial in 20,536 individuals

BACKGROUND

Statin therapy reduces the rates of heart attack, stroke, and revascularisation among a wide range of individuals. Reliable assessment of its cost-effectiveness in different circumstances is needed.

METHODS

20,536 adults (aged 40-80 years) with vascular disease or diabetes were randomly allocated 40 mg simvastatin daily (10,269) or placebo (10,267) for an average of 5 years. Comparisons were made of hospitalisation and statin costs (2001 UK prices) during the scheduled treatment period between all simvastatin-allocated versus all placebo-allocated participants. Cost-effectiveness was estimated among different categories of participant.

FINDINGS

Allocation to simvastatin was associated with a highly significant 22% (95% CI 16-27; p<0.0001) proportional reduction in hospitalisation costs for all vascular events, with similar proportional reductions in every subcategory of participant studied. During an average of 5 years, estimated absolute reductions in vascular event costs per person allocated 40 mg simvastatin daily ranged from UK 847 pounds sterling (SE 137) in the highest risk quintile studied to 264 pounds sterling (48) in the lowest. Mean excess cost of statin therapy among participants allocated simvastatin was 1497 pounds sterling (8), with similar absolute increases in every subcategory. Costs of preventing a major vascular event with 40 mg simvastatin daily ranged from 4500 pounds sterling (95% CI 2300-7400) among participants with a 42% 5-year major vascular event rate to 31,100 pounds sterling (22,900-42,500) among those with a 12% rate (corresponding to 5-year major coronary event rates of 22% and 4%, respectively).

INTERPRETATION

Statin therapy is cost effective for a wider range of individuals with vascular disease or diabetes than previously recognised (particularly with lower-priced generics). It would be appropriate to consider reducing the estimated level of vascular event risk at which statin therapy is recommended.

Cost of lipid lowering in patients with coronary artery disease by Case Method Learning

Objectives:This investigation was undertaken to study the costs of a Case Method Learning (CML) -supported lipid-lowering strategy in secondary prevention of coronary artery disease (CAD) in primary care.

Methods:This prospective randomized controlled trial in primary care with an additional external specialist control group in Södertälje, Stockholm County, Sweden, included 255 consecutive patients with CAD. Guidelines were mailed to all general practitioners (GPs; n=54) and presented at a common lecture. GPs who were randomized to the intervention group participated in recurrent CML dialogues at their primary health-care centers during a 2-year period. A locally well-known cardiologist served as a facilitator. Assessment of low-density lipoprotein (LDL) cholesterol was performed at baseline and after 2 years. Analysis according to intention-to-treat—intervention and control groups (n=88)—was based on group affiliation at baseline. The marginal cost of lipid lowering comprised increased cost of lipid-lowering drugs in the intervention group compared with the primary care control group, cost of attendance of the GP's in the intervention group, and cost of time for preparation, travel, and seminars of the facilitator. Costs are as of 2002 with an exchange rate 1 US$=9.5 SEK (Swedish Crowns).

Results:Patients in the primary care intervention group had their LDL cholesterol reduced by 0.5 (confidence interval [CI], 0.1–0.9) mmol/L compared with the primary care control group (p<.05). No change occurred in controls. LDL cholesterol in the external specialist control group decreased by 0.6 (CI, 0.4–0.8) mmol/L. The cost of the educational intervention represented only 2 percent of the drug cost. The cost of lipid lowering in the intervention group, including the cost of the educational intervention, was actually lower than that of patients treated at the specialist clinic—106 US$ per mmol decrease in LDL cholesterol in the intervention group and 153 US$ per mmol decrease in LDL cholesterol in the specialist group. EuroQol 5D Index, which gives an estimate of global health-related quality of life, was 0.80 (CI, 0.75–0.85) in the present cohort.

Conclusions:The additional cost of CML was only 2 percent of the drug cost. Assuming the same gain in life expectancy per millimole decrease in LDL cholesterol as in the 4S-study gives a cost per gained quality-adjusted life year of US$ 24,000. This finding indicates that the CML-supported lipid-lowering strategy is cost-effective. The low cost of CML in primary care should probably warrant its use in the improvement of the quality of care in other major chronic diseases.

Conducting economic evaluations alongside multinational clinical trials: toward a research consensus

Demand for economic evaluations in multinational clinical trials is increasing, but there is little consensus about how such studies should be conducted and reported. At a workshop in Durham, North Carolina, we sought to identify areas of agreement about how the primary findings of economic evaluations in multinational clinical trials should be generated and presented. In this paper, we propose a framework for classifying multinational economic evaluations according to (a) the sources of an analyst's estimates of resource use and clinical effectiveness and (b) the analyst's method of estimating costs. We review existing studies in the cardiology literature in the context of the proposed framework. We then describe important methodological and practical considerations in conducting multinational economic evaluations and summarize the advantages and disadvantages of each approach. Finally, we describe opportunities for future research. Delineation of the various approaches to multinational economic evaluation may assist researchers, peer reviewers, journal editors, and decision makers in evaluating the strengths and limitations of particular studies.

Variability of cost-effectiveness estimates for pharmaceuticals in Western Europe: lessons for inferring generalizability

OBJECTIVES

It has long been suggested that, whereas the results of clinical studies of pharmaceuticals are generalizable from one jurisdiction to another, the results of economic evaluations are location dependent. There has been, however, little study of the causes of variation, whether differences in study results among countries are systematic, or whether they are important for decision making.

METHODS

A literature search was conducted to identify economic evaluations of pharmaceuticals conducted in two or more European countries. The studies identified were then classified by methodological type and analyzed to assess their level of variability and to identify the main causes of variation. Assessments were also made of the extent to which differences in study results among countries were systematic and whether they would lead to a different decision, assuming a range of values of the threshold willingness-to-pay for a life-year or quality-adjusted life-year (QALY).

RESULTS

In total 46 intercountry drug comparisons were identified, 29 in multicountry studies and 17 in comparable single country studies that were considered to be sufficiently similar in terms of methodology. The type of study (i.e., trial-based or modeling study) had some impact on variability, but the most important factor was the extent of variation across countries in effectiveness, resource use or unit costs, allowed by the researcher's chosen methodology. There were few systematic differences in study results among countries, so a decision maker in country B, on seeing a recent economic evaluation of a new drug in country A, would have little basis on which to predict whether the drug, if evaluated, would be more or less cost-effective in his or her country. Given the extent of variation in cost-effectiveness estimates among countries, the importance of this for decision making depends on decision makers' thresholds in willingness-to-pay for a QALY or life-year. If a cost-effectiveness threshold (i.e., willingness-to-pay) for a life-year or QALY of dollar 50,000 were assumed, the same conclusion regarding cost-effectiveness would be reached in most cases.

CONCLUSION

This review shows that cost-effectiveness results for pharmaceuticals vary from country to country in Western Europe and that these variations are not systematic. In addition, constraints imposed by analysts may reduce apparent variability in the estimates. The lessons for inferring generalizability are not straightforward, although the implications of variation for decision making depend critically on the cost-effectiveness thresholds applying in Western Europe.

Estimating survival for cost-effectiveness analyses: a case study in atherothrombosis

BACKGROUND

Economic evaluations typically require estimates of survival beyond the limited follow-up in clinical trials. The objective of this study was to demonstrate a data-driven approach to deriving these estimates.

METHODS

To provide survival estimates for analyses of the CAPRIE trial, data were obtained from Saskatchewan on more than 50,000 patients like those in the trial: diagnosed with peripheral arterial disease (PAD), myocardial infarction, or ischemic stroke between 1985 and 1995; follow-up to December 31, 2000. Mean survival was estimated by integrating the full survival curve derived by applying hazard functions over time. Cox proportional hazards analyses were carried out in each of four periods defined to ensure proportionality.

RESULTS

Adjusting for mean age in CAPRIE, mean survival ranged from 12.1 years after index stroke to 13.6 years after diagnosis of PAD. Comorbidities reduced mean survival by 1 to 2 years. Subsequent events had a marked detrimental effect, decreasing life-expectancy by 50% or more, and disease in multiple vascular beds led to survival of less than 5 years.

DISCUSSION

These analyses demonstrate the analytic methods required to accurately estimate survival. The trial ages were much lower than in the observational study. Thus, the estimates are optimistic for the general population.

CONCLUSIONS

Accurate valuation of interventions depends on valid survival estimates. These analyses confirm that survival is significantly reduced in patients with atherothrombotic disease, particularly with additional comorbidities.

Cost-effectiveness of clopidogrel in acute coronary syndromes in Sweden: a long-term model based on the CURE trial

OBJECTIVES

The purpose of this study was to evaluate the long-term cost-effectiveness of clopidogrel on top of standard therapy (including ASA) in patients with acute coronary syndromes without ST-segment elevation in Sweden.

METHODS AND RESULTS

Incremental cost-effectiveness ratios (ICER) were assessed using a Markov model with transition probabilities estimated from the Swedish hospital discharge and cause of death registers. Patients were assumed to be treated for 1 year, with treatment effects (RR = 0.8) and costs taken from the Clopidogrel in Unstable Angina to prevent Recurrent ischaemic Events Trial. Two scenarios were analysed: with patients similar to those in the trial and with patients similar to those from the register. In the first scenario, the predicted net direct cost was 160 euro and the net total cost -54 euro, which with an incremental survival of 0.12 years give the ICER of 1365 euro per life-year gained from the health care payer perspective (including direct costs) and cost savings from the societal perspective (also including indirect costs). The net costs in the second scenario were 149 euro, giving an ICER of 1009 euro for both perspectives.

CONCLUSIONS

Adding clopidogrel to standard therapy including ASA is cost-effective in the studied setting and compares favourably with other cardiovascular treatment and prevention strategies.

Cost effectiveness of HMG-CoA reductase inhibitors in the management of coronary artery disease: the problem of under-treatment

HMG-CoA reductase inhibitors significantly reduce the risk of coronary artery disease (CAD) events and CAD-related mortality in patients with and without established CAD. Consequently, HMG-CoA reductase inhibitors have a central role within recommendations for lipid-modifying therapy. However, despite these guidelines, only one-third to one-half of eligible patients receive lipid-lowering therapy and as few as one-third of these patients achieve recommended target serum levels of low density lipoprotein-cholesterol. The underuse of HMG-CoA reductase inhibitors in eligible patients has important implications for mortality, morbidity and cost, given the enormous economic burden associated with CAD; direct healthcare costs, estimated at US $16-53 billion (2000 values) in the US and 1.6 billion pound (1996 values) in the UK alone, are largely driven by inpatient care. Hospitalization costs are reduced by treatment with HMG-CoA reductase inhibitors, particularly in high-risk groups such as patients with CAD and diabetes mellitus in whom net cost savings may be achieved. HMG-CoA reductase inhibitors are underused because of institutional factors and clinician and patient factors. Also, the vast number of patients eligible for treatment means that the use of HMG-CoA reductase inhibitors is undoubtedly limited by budgetary considerations. Secondary prevention in CAD using HMG-CoA reductase inhibitors is certainly cost effective. Primary prevention with HMG-CoA reductase inhibitors is also cost effective in many patients, depending upon CAD risk and drug dosage. As new, more powerful, HMG-CoA reductase inhibitors come to market, and the established HMG-CoA reductase inhibitors come off patent, the identification of the most cost-effective therapy becomes increasingly complex. Research in to the relative cost effectiveness of alternative HMG-CoA reductase inhibitors, taking full account of the institutional, clinician and patient barriers to uptake should be undertaken to identify the most appropriate role for the new therapies.

Cost-effectiveness of ezetimibe coadministration in statin-treated patients not at cholesterol goal: application to Germany, Spain and Norway

BACKGROUND

Despite the growing use of statins, many hypercholesterolaemic patients fail to reach their lipid goal and remain at elevated risk of coronary heart disease (CHD). Alternative treatment strategies, such as ezetimibe coadministration and statin titration, can help patients achieve greater lipid control, and thereby lower their CHD risk. But is it cost effective to more aggressively lower cholesterol levels across a broad range of current statin users?

METHODS

Using a decision-analytic model based on epidemiological and clinical trials data, we project the lifetime benefit and cost of alternative lipid-lowering treatment strategies for CHD and non-CHD diabetic patients in Germany, Spain and Norway.

RESULTS

It is projected that from 40% to 76% of these patients who have failed to reach their lipid goal with their current statin treatment will be able to reach their goal with ezetimibe coadministration; this represents a gain of up to an additional absolute 14% who will be able to reach their goal compared with a 'titrate to goal' strategy where patients are titrated in order to reach their lipid goal (up to the maximum approved dose). For CHD patients, the estimated incremental cost-effectiveness ratio for ezetimibe coadministration is under Euro 18 000 per life-year gained (Euro/LYG) and 26 000 Euro/LYG compared with strategies based on the observed titration rates and the aggressive 'titrate to goal' strategy, respectively; for non-CHD diabetic patients, these ratios are under 26 000 Euro/LYG and 48 000 Euro/LYG for ezetimibe coadministration compared with the two titration strategies.

CONCLUSION

Compared with statin titration, ezetimibe coadministration is projected to be cost effective in the populations and countries studied.

Pharmacoeconomic evaluation of testing for angiotensin-converting enzyme genotype before starting ??-hydroxy-??-methylglutaryl coenzyme A reductase inhibitor therapy in men

This study aimed to assess the potential cost-effectiveness of screening men for their angiotensin-converting enzyme (ACE)-genotype before starting statin therapy. We used a combination of decision-analytic and Markov modelling techniques to evaluate the long-term incremental clinical and economic effects associated with genetic testing of men with hypercholesterolemia before starting treatment with statins. The study was performed from a health care payer perspective. We used data from the Rotterdam study, a prospective population-based cohort study in the Netherlands, which was started in 1990 and included 7983 subjects aged 55 years and older. Men treated with cholesterol-lowering drugs at baseline or with a baseline total cholesterol > or = 6.5 mmol/l were included. The ratio of difference in lifelong costs between the screening strategy and the no screening strategy to difference in life expectancy between these strategies was calculated. We also performed a cost-utility analysis. The base case was a 55-year-old man with hypercholesterolemia who was initially untreated. Several univariate sensitivity analyses were performed. All costs were discounted with an annual rate of 5%. Screening men for their ACE-genotype was the dominant strategy for the base case analysis, because the screening strategy saved money (851 Euro), but life expectancy was not changed. Screening was the dominant strategy for all age-groups in our cohort. Even in 80-year-old subjects, with the shortest life-expectancy, it was cheaper to screen than to give lifelong treatment to men with a DD genotype without success. Even if all DD subjects were treated with other (non-statin) cholesterol-lowering drugs, screening remained the cost-effective strategy. The results of the cost-utility analysis were similar. Discounting the effects with 5% per year also had no major impact on the conclusions. If other studies confirm that men with the DD genotype do not benefit from treatment with statins, screening for ACE genotype in men most likely will be a cost-effective strategy before initiating statin therapy.

Examining within-country variation of maternity costs in the context of a multicountry, multicentre randomised controlled trial

Understanding why healthcare costs vary between patients and between health facilities is important in guiding health policy decisions as well as in research. However, there is no comprehensive framework that analysts commonly use for expressing and examining causes of cost variation in the field of healthcare. The aim of this study is to better understand the size and causes of within-country healthcare cost variation, through presenting evidence for size and sources of such variations for two countries (Cuba and Thailand) in the context of a randomised controlled trial on antenatal care. The article separates total costs into their two components: unit costs and health service use. Unit costs are further separated into input quantity per patient visit or day, and the prices of these resources. The results show that the main determinant of average cost is the staffing pattern and productivity, whereas the main determinants of health service use include the model of antenatal care being practised and the risk status and illnesses suffered by patients. However, variations in inpatient health service use between facilities are largely related to unexplainable variations in practice between facilities, irrespective of the trial arm. In conclusion, cost variations have important implications for the design of clinical trials and for policy makers using evidence from trials in planning health services and budgets.

The value of clopidogrel in addition to standard therapy in reducing atherothrombotic events

The recent multinational, randomised, prospective studies Clopidogrel in Unstable Angina to Prevent Recurrent Events (CURE), Percutaneous Coronary Intervention substudy of CURE (PCI-CURE) and Clopidogrel for the Reduction of Events During Observation (CREDO) have demonstrated the clinical efficacy and safety of clopidogrel for the treatment of patients with non-ST-segment elevation acute coronary syndromes (ACS), including those undergoing percutaneous coronary intervention. In these settings, clopidogrel significantly reduces the risk of atherothrombotic events, with relative risk reductions of 20-30% (absolute risk reduction 1.9-3.0%). Health economic evaluations based on data from these studies conducted in Europe and the United States have clearly demonstrated the cost-effectiveness of clopidogrel in combination with aspirin compared with aspirin alone for the management of ACS. Within-trial evaluations based on CURE and PCI-CURE data showed that treatment with clopidogrel on top of standard therapy reduced the cost of initial hospitalisation as well as the total cost associated with hospitalisations. Long-term economic analyses based on the CURE study demonstrate that clopidogrel is cost saving in the Netherlands and that the cost per life-year gained (LYG) in other European countries is between Euros 549 and Euros 5048. In the United States, the cost per LYG for clopidogrel has been assessed at US dollars 6173 on the basis of CURE, US dollars 5910 for PCI-CURE and US dollars 3685 for CREDO, all of which are considerably lower than that associated with common cardiovascular benchmarks. The results are robust and consistent across different countries using varying costing strategies and estimates of survival. In conclusion, these data demonstrate that clopidogrel in combination with aspirin for the management of ACS is both clinically effective and cost-effective in this setting.

Unit costs in international economic evaluations: resource costing of the Schizophrenia Outpatient Health Outcomes Study

OBJECTIVE

We present unit costs corresponding to resource information collected in the Schizophrenia Outpatient Health Outcomes (SOHO) Study.

METHOD

The SOHO study is a 3-year, prospective, observational study of health outcomes associated with antipsychotic treatment in out-patients treated for schizophrenia. The study is being conducted across 10 European countries (Denmark, France, Germany, Greece, Ireland, Italy, the Netherlands, Portugal, Spain and the UK) and includes over 10,800 patients and over 1000 investigators. To identify the best available unit costs of hospital admissions, day care and psychiatrist out-patient visits, a tariff-based approach was used.

RESULTS

Unit costs were obtained for nine of the 10 countries and were adjusted to 2000 price levels by consumer price indices and converted to US dollars using purchasing power parity rates (and on to Euro).

CONCLUSION

The paper illustrates the need to balance the search for sound unit costs with pragmatic solutions in the costing of international economic evaluations.

Cytomegalovirus disease following liver transplantation: an analysis of prophylaxis strategies

BACKGROUND

Cytomegalovirus (CMV) infection is an important cause of morbidity and mortality following liver transplantation. Though oral ganciclovir may be used as a prophylactic agent, there is some debate as to whether prophylaxis should be given universally or to targeted 'high risk' sub-groups. We, therefore, analysed the cost-effectiveness of both prophylactic strategies.

METHODS

We performed a retrospective cross-sectional study of adult liver transplant (LT) recipients who developed CMV disease in 1997 and estimated the morbidity and costs associated with disease in these patients. These costs were compared with the estimated cost (based on a previous multi-centre study) of using oral ganciclovir prophylaxis in order to assess the potential cost-effectiveness of introducing different prophylactic regimes.

RESULTS

Universal and targeted prophylaxis would both have prevented all the likely mortality (2 deaths) from CMV disease in that year. The net cost of applying a targeted prophylaxis strategy would have been 206,275 pounds, (i.e. 103,137 pounds per death avoided). The cost per life year saved would have been 15,674 pounds.

CONCLUSION

We suggest that LT units should identify patients at high risk for the development of CMV disease and adopt a targeted prophylactic strategy.

Statin therapy in the elderly: does it make good clinical and economic sense?

HMG-CoA reductase inhibitors (statins) have been established as the dominant treatment for coronary heart disease (CHD). This dominance is based on an impressive body of clinical trial evidence showing significant benefits in primary prevention of cardiovascular events in individuals at risk for CHD and in secondary prevention of such events in patients with CHD and high or normal plasma cholesterol levels. There is, however, significant room for improvement in the treatment of CHD with respect both to drug efficacy and to the disparity between evidence-based medicine and actual clinical practice particularly in relation to treatment strategies for the elderly. Current statins fall short of requirements for 'ideal' lipid-lowering treatment in several respects; 'super' statins and other agents currently in development may satisfy more of these requirements. Moreover, available therapies are not applied optimally, because of physician nonacceptance and/or patient noncompliance; thus, the majority of patients with CHD or its risk factors still have cholesterol levels that exceed guideline targets. There is also evidence that older patients with CHD, or at high risk of CHD, are undertreated - possibly because of concerns regarding the increased likelihood of adverse events or drug interactions or doubts regarding the cost effectiveness of statin therapy in this population. This group is of particular clinical relevance, since it is showing a proportionate rapid expansion in most national populations. To address their potential healthcare needs, the ongoing Pravastatin in the Elderly at Risk (PROSPER) study is assessing the effects of pravastatin in elderly patients (5804 men and women aged 70-82 years) who either have pre-existing vascular disease or are at significant risk for developing it, with the central hypothesis that statin therapy (pravastatin 40 mg/day) will diminish the risk of subsequent major vascular events compared with placebo. After a 3.2-year treatment period, a primary assessment will be made of the influence of statin treatment on major cardiovascular events (a combination of CHD death, nonfatal myocardial infarction, and fatal or nonfatal stroke). Optimal deployment of the currently available agents and of newer agents (no matter how well they satisfy requirements for ideal treatment) ultimately depends on the establishment of an evidence base and may require far-reaching educational programmes that change the way risk factor management is viewed by caregivers and patients alike.

Assessing the appropriateness of combining economic data from multinational clinical trials

Because of the potential for large variability among countries in the utilization and cost of health care resources, it is important to assess the appropriateness of combining economic data across the countries in a multinational clinical economic trial. We show how available tests for interaction can be applied to economic endpoints, including cost-effectiveness ratios and net health benefits. This analysis includes a characterization of possible interactions being quantitative or qualitative in nature. In the absence of interaction, a pooled estimate of the economic endpoint should be representative of the participating countries. We explore the analytic issues by further analysing data from the Scandinavian Simvastatin Survival Study (4S).

Smoking: can we really make a difference?

The enormous health benefits of stopping smoking are now well established. Doctors have a vital role in motivating smokers and initiating quit attempts. The mainstay of National Health Service smoking cessation strategy should be the routine provision of brief opportunistic intervention in primary care, backed up by referral to a specialist smoking cessation service. There is an urgent need to increase substantially the numbers of smokers referred by general practitioners, other members of the primary care team, and those working in acute hospital trusts, to specialist smoking cessation services and for better channels of communication between the various agencies. Use of pharmacotherapy (nicotine replacement therapy or bupropion) in combination with behavioural support achieves higher cessation rates than either component alone and is the most effective way of helping smokers to stop. Smokers who quit often relapse and hence will need repeated help.

Health economics in the Hypertension Optimal Treatment (HOT) study: costs and cost-effectiveness of intensive blood pressure lowering and low-dose aspirin in patients with hypertension

OBJECTIVES

To investigate the marginal cost-effectiveness of different targets for the reduction of blood pressure and the cost-effectiveness of adding acetylsalicylic acid (ASA) to the treatment of hypertension.

DESIGN

Patients with hypertension were randomized to three target groups for blood pressure; < or =90, < or =85 and < or =80 mmHg. Patients were also randomly assigned ASA and placebo. The average follow-up time was 3.8 years. The direct costs for drugs, visits, hospitalizations, and side-effects were calculated and related to clinical outcome.

SETTING

Resource utilization data from all the 26 countries in the study were pooled, and Swedish unit costs were applied to the aggregated resource utilization.

SUBJECTS

A total of 18 790 patients, 50-80 years of age (mean 61.5 years), with a diastolic blood pressure between 100 and 115 mmHg (mean 105 mmHg).

INTERVENTIONS

Antihypertensive treatment with the long-acting calcium antagonist felodipine was given to all patients. Additional therapy and dose increments in four further steps were prescribed to reach the randomized target blood pressure. Fifty per cent of the patients were randomized to a low dose, 75 mg daily, of acetylsalicylic acid.

MAIN OUTCOME MEASURES

Direct health care costs, major cardiovascular (CV) events (myocardial infarction and stroke) and CV death.

RESULTS

The average cost of drugs and visits increased with more intensive treatment. The increase in treatment costs was partly but not fully offset by a nonsignificant reduction in the cost of CV hospitalizations. For patients with diabetes there were no significant differences in total cost between the target groups. The cost of avoiding a major CV event was negative in the base case analysis, SEK -10 360 (CI: -78 195, 75 630), and SEK 18 450 (CI: -88 789, 192 980) in a sensitivity analysis. For patients on ASA, costs were slightly but significantly higher than for patients on placebo. The estimates of the cost of avoiding a major CV event varied between SEK 41 600 and SEK 477 400, with very wide confidence intervals.

CONCLUSIONS

The treatment cost increases as the target for hypertension treatment is lowered. In patients with diabetes, intensive treatment to a lower target is cost-effective. Because of the nonsignificant difference in events, no conclusion can be made for all patients in the study. Furthermore, no conclusive evidence was found regarding the cost-effectiveness of adding ASA to the treatment of hypertension.

Cost-effectiveness of primary prevention of coronary heart disease through risk factor intervention in 60-year-old men from the county of Stockholm--a stochastic model of exercise and dietary advice

BACKGROUND

Recent screenings show a high prevalence of cardiovascular risk factors in the county of Stockholm. Primary prevention may be a way to lower the risk burden of coronary heart disease, but we must establish that preventive programs are cost-effective.

METHODS

Through the use of a stochastic Markov model, which predicts reduction in coronary heart disease events based on risk factor reductions, this study evaluates the results of a previous controlled trial in middle-aged men comparing dietary advice, exercise, and the combination of both applied to an observed cohort of 60-year-old men in the county of Stockholm.

RESULTS

The model predicts lower costs and higher effectiveness for dietary advice compared to the alternatives. Assuming a declining effect of the intervention, dietary advice saves 0.0228 life-years compared to no intervention. If no decline is assumed, the corresponding figure is 0.0997 life-years. From the societal perspective, the added costs are 2,892 Swedish Kronor (SEK) and 14,106 SEK for the two modeling assumptions, resulting in a cost-effectiveness of 127,065 SEK per life-year gained (LYG) and 141,555 SEK/LYG. These figures are below what is generally thought of as cost-effective.

CONCLUSION

Based on the model, dietary advice appears to be the most cost-effective of the studied interventions.

A model to assess the cost effectiveness of statins in achieving the UK National Service Framework target cholesterol levels

BACKGROUND

Coronary heart disease (CHD) is a public health priority in the UK. The National Service Framework (NSF) has set standards for the prevention, diagnosis and treatment of CHD, which include the use of cholesterol-lowering agents aimed at achieving targets of blood total cholesterol (TC) < 5.0 mmol/L and low density lipoprotein-cholesterol (LDL-C) < 3.0 mmol/L. In order to achieve these targets cost effectively, prescribers need to make an informed choice from the range of statins available.

AIM

To estimate the average and relative cost effectiveness of atorvastatin, fluvastatin, pravastatin and simvastatin in achieving the NSF LDL-C and TC targets.

DESIGN

Model-based economic evaluation.

METHODS

An economic model was constructed to estimate the number of patients achieving the NSF targets for LDL-C and TC at each dose of statin, and to calculate the average drug cost and incremental drug cost per patient achieving the target levels. The population baseline LDL-C and TC, and drug efficacy and drug costs were taken from previously published data. Estimates of the distribution of patients receiving each dose of statin were derived from the UK national DIN-LINK database.

RESULTS

The estimated annual drug cost per 1000 patients treated with atorvastatin was pound 289000, with simvastatin pound 315000, with pravastatin pound 333000 and with fluvastatin pound 167000. The percentages of patients achieving target are 74.4%, 46.4%, 28.4% and 13.2% for atorvastatin, simvastatin, pravastatin and fluvastatin, respectively. Incremental drug cost per extra patient treated to LDL-C and TC targets compared with fluvastatin were pound 198 and pound 226 for atorvastatin, pound 443 and pound 567 for simvastatin and pound 1089 and pound 2298 for pravastatin, using 2002 drug costs.

CONCLUSIONS

As a result of its superior efficacy, atorvastatin generates a favourable cost-effectiveness profile as measured by drug cost per patient treated to LDL-C and TC targets. For a given drug budget, more patients would achieve NSF LDL-C and TC targets with atorvastatin than with any of the other statins examined.

Do HEDIS measures reflect cost-effective practices?

PURPOSE

Whether the Health Plan Employer Data and Information Set (HEDIS) performance measures for managed care plans encourage a cost-effective use of society's resources has not been quantified. Our study objectives were to examine the cost-effectiveness evidence for the clinical practices underlying HEDIS 2000 measures and to develop a list of practices not reflected in HEDIS that have evidence of cost effectiveness.

DATA SOURCES

Two databases of economic evaluations (Harvard School of Public Health Cost-Utility Registry and the Health Economics Evaluation Database) and two published lists of cost-effectiveness ratios in health and medicine.

STUDY SELECTION

For each of the 15 "effectiveness of care" measures in HEDIS 2000, we searched the data through 1998 for cost-effectiveness ratios of similar interventions and target populations. We also searched for important interventions with evidence of cost-effectiveness (<$20,000 per life-year [LY] or quality-adjusted life year [QALY] gained), which are not included in HEDIS. All ratios were standardized to 1998 dollars. The data were collected and analyzed during fall 2000 to summer 2001.

DATA EXTRACTION

Cost-effectiveness ratios reporting outcomes in terms of cost/LY or cost/QALY gained were included if they matched the intervention and population covered by the HEDIS measure.

DATA SYNTHESIS

Evidence was available for 11 of the 15 HEDIS measures. Cost-effectiveness ranges from cost saving to $660,000/LY gained. There are numerous non-HEDIS interventions with some evidence of cost effectiveness, particularly interventions to promote healthy behaviors.

CONCLUSIONS

HEDIS measures generally reflect cost-effective practices; however, in a number of cases, practices may not be cost effective for certain subgroups. Data quality and availability as well as study perspective remain key challenges in judging cost effectiveness. Opportunities exist to refine existing measures and to develop additional measures, which may promote a more efficient use of societal resources, although more research is needed on whether these measures would also satisfy other desirable attributes of HEDIS.

Daily dosing versus alternate-day dosing of simvastatin in patients with hypercholesterolemia

STUDY OBJECTIVE

To compare the efficacy of daily simvastatin administration with that of alternate-day therapy at double the daily dose.

DESIGN

Nonrandomized, before-after comparison trial.

SETTING

Outpatient clinic of a Veterans Affairs medical center.

PATIENTS

Fifteen men with hyperlipidemia.

INTERVENTION

The simvastatin regimen for patients with a low-density lipoprotein cholesterol (LDL) level at their established National Cholesterol Education Program goal was converted from daily dosing to double the daily dose given every other day for 8 weeks.

MEASUREMENTS AND MAIN RESULTS

Baseline laboratory values were obtained for patients receiving daily simvastatin therapy After 8 weeks of alternate-day therapy, follow-up laboratory values were obtained and assessed for efficacy and toxicity. The LDL-lowering effect of the daily dosing regimen was compared with that of the alternate-day dosing regimen. Paired t tests were computed to compare LDL concentrations before and after the study using a 95% confidence interval. No statistically significant difference was observed.

CONCLUSION

Alternate-day dosing of simvastatin may be an effective alternative to daily dosing.

The cost-effectiveness of ramipril in the treatment of patients at high risk of cardiovascular events: a Swedish sub-study to the HOPE study

OBJECTIVE

To evaluate if long-term treatment with ramipril is cost-effective in patients at high risk of cardiovascular events.

DESIGN

Randomized double-blind and placebo controlled. Information was gathered prospectively for a number of direct medical, direct nonmedical and indirect costs.

SETTING AND SUBJECT

This is a sub-study to the Heart Outcomes Prevention Evaluation (HOPE) study performed in Swedish patients. All Swedish centres (19; n= 554) were invited to take part and 18 centres agreed to do so (n=537). The patients were managed in a specialist setting with a mean follow-up period of 4.5 years. Main outcome measures. The number of life-years saved was derived from the global HOPE study (n=9297) and subsequently the estimated life expectancy of those who completed the clinical study alive was added to the calculation. Direct medical costs related to cardiovascular disease only were considered in the primary analysis, whilst all kinds of costs and costs for all kinds of diseases were included in subsequent analyses. The cost of added years of life, according to the future cost method, was included in sensitivity analyses.

RESULTS

The cost per life-year gained was SEK 16 600 (Euro 1940) when direct medical costs for cardiovascular reasons only were considered and SEK 45 400 (Euro 5300) when direct medical costs for all diseases were considered. The corresponding costs when direct nonmedical and indirect cost were added to the estimate were SEK 16 100 (Euro 1880) and SEK 54 600 (Euro 6380), respectively. When the future cost method was applied, the cost per life-year gained was SEK 208 300 (Euro 24 300).

CONCLUSION

Ramipril is highly cost-effective in the treatment of patients at high risk of cardiovascular events.

Costs for screening, intervention and hospital treatment generated by the Malmö Preventive Project: a large-scale community screening programme

OBJECTIVES

The purpose of this study was to estimate retrospectively the costs of health care resources used in the Malmö Preventive Project, Sweden and estimate the costs of in-patient care that were avoided because of early intervention.

SETTING AND SUBJECTS

A large-scale community intervention programme was conducted from 1974 to 1992 in Malmö, Sweden with the aim of reducing morbidity and mortality of cardiovascular diseases (CVD), alcohol related illnesses, and breast cancer. Between 1974 and 1992, 33 336 male and female subjects were screened for hypertension, hyperlipidaemia, type-2 diabetes and alcohol abuse. Intervention programmes that included life-style modifications, follow-up visits with physicians and nurses and drug therapy were offered to about 25% of screened subjects.

METHODS

Recruitment costs were generated through out the screening period. Intervention costs were estimated for 5 years after screening. Excess in-patient care costs were estimated by subtracting hospital consumption for an unscreened, matched cohort from that of the screened cohort over follow-up periods of 13-19 years. Intervention and excess in-patient care costs were estimated until 1996.

RESULTS

The net expenditures for recruitment and intervention was SEK253 million and saved costs for in-patient care of SEK143 millions (1998 prices). Considering the opportunity cost of the resources used in the study, the net cost rises to about SEK200 millions.

CONCLUSIONS

The results suggest that only part of the intervention costs were offset by reduction in future morbidity health care costs. This is in line with results from prospective analyses of other primary prevention programmes.

Design, analysis and presentation of multinational economic studies: the need for guidance

Over the last decade, there has been a proliferation in the number of economic evaluations of pharmaceuticals to meet the growing demand for information about the economic benefits of healthcare technologies. The majority of these studies have been commissioned by pharmaceutical companies for the purposes of drawing attention to the resource and quality-of-life aspects of new or existing products. Such information has become important in overcoming a new obstacle, namely the demonstration of cost effectiveness (the so-called 'fourth hurdle'), in addition to the three well-established criteria of quality, tolerability and efficacy. To ensure the maintenance of standards, guidance for economic evaluations has emerged lately in the form of guidelines, regulations, principles, policies and positions. Drummond outlined three purposes of these guidelines, as follows: as a requirement prior to reimbursement, as statements of methodological standards, and as a statement of ethical standards. Such guidelines are designed to assist both the economic analyst and the decision-maker. In laying out the state of the art regarding the methodology of economic evaluation, guidelines assist the analyst in performing high-quality, scientifically valid studies, and assist the decision-maker in properly interpreting and assessing their quality. In response to these growing requirements for cost-effectiveness data globally, it has become increasingly common for economic evaluations to be conducted on an international scale. However, the recommendations in pharmacoeconomics guidelines regarding the manner in which these multinational economic evaluations should be designed, analysed and presented are too limited to be of any real value. This article examines the various issues that must be taken into consideration when conducting multinational studies, and provides a review of the techniques and approaches that have been suggested to date. It concludes with recommendations for potential inclusion in future sets of pharmacoeconomic guidelines.

Economics of drug treatment: for which patients is it costeffective to lower cholesterol?

Today's society places a great emphasis on value for money, so medical interventions must not only be shown to be effective but also be proved to be costeffective. Drug treatment is no exception. In health economics, costeffectiveness is calculated differently depending on the indication and the perspective. For cholesterol-lowering drugs (as an example) there is a difference between primary and secondary intervention. In primary prevention, the cut off value for absolute risk when treatment is costeffective varies with age and sex, but in secondary prevention, although treatment is costeffective for all groups of patients, costeffectiveness varies with age, sex, cholesterol concentration, and other risk factors. There are three complementary approaches to economic assessment of secondary prevention-analysis of the whole population, subgroup analysis, and modelling.