Which statin is most efficient for the treatment of hypercholesterolemia? A cost-effectiveness analysis

Optimal statin type and dosage for vascular patients

Statins are an essential component of the management of patients suffering from vascular diseases. As there is neither any consensus nor any guidelines regarding this issue, we aimed to define the optimal statin type and dosage for these patients. MEDLINE was searched for studies comparing different statin types and dosages for vascular patients. In the absence of adverse effects, rosuvastatin or atorvastatin ≥ 20 mg/d is the optimal statin type and dosage for vascular patients. The management of statin-induced adverse events and the options for statin-intolerant patients are also discussed. Routine statin treatment is associated with several beneficial effects in vascular patients whether managed conservatively or undergoing open vascular surgery/endovascular interventions. If possible, statins should not be discontinued before open or endovascular procedures and treatment should be resumed as soon as possible. Future studies should evaluate the effects of an increased statin loading dose prior to vascular procedures.

How inducing covariation in simulated HDL-C, triglyceride, and total cholesterol data affects Framingham risk equation results

OBJECTIVE

To assess the effect of inducing covariation among simulated high-density lipoprotein (HDL-C), triglyceride, and total cholesterol values on Framingham risk equation results.

METHODS

National Health and Nutrition Examination Survey (NHANES) data were used to estimate means and standard deviations for HDL-C, triglyceride, and total cholesterol for all Type II diabetic patients (N = 293) and patients with metabolic syndrome (N = 2303). NHANES data were also used to estimate correlations between HDL-C, triglyceride, and total cholesterol. Data were simulated and bootstrapped for 1000 replications of the numbers of patients in NHANES. Four-year risks of coronary heart disease were estimated using the Framingham risk equation that includes a nonlinear Weibull function. The differences in means, with and without correlation, were compared to zero to determine whether not inducing correlation was associated with bias. The ratios of variances with and without correlation were compared to one to determine whether not inducing correlation was associated with a different level of precision. All simulation results were compared with bootstrapping results.

RESULTS

Bootstrapping maintained the correlation in the original data. Inducing correlation leads to more precise estimates that are closer to the bootstrapped estimates for Framingham equations not including triglycerides. Using the Framingham equation for women with triglycerides, the correlated simulation data produce less precise estimates than the uncorrelated data; the uncorrelated data are more precise than the bootstrapped results.

CONCLUSION

Not inducing correlation can affect results that combine multiple simulated parameters using nonlinear functions. Researchers engaged in modeling should consider the value of inducing correlation in their simulated data.

Methods for integrating medication compliance and persistence in pharmacoeconomic evaluations

OBJECTIVES

Suboptimal compliance and failure to persist with drug treatments are important determinants of therapeutic nonresponse and are of potential economic significance. The present article aims to describe the methodologies that may be appropriate for integrating noncompliance and nonpersistence in economic evaluations.

METHODS

MEDLINE and NHS-EED were searched for economic evaluations published in the period between 1997 and 2005. Articles were included if they explored the dependence of cost-effectiveness results on varying levels of some form of compliance-related measure. The different methodologies used were reviewed and articles were appraised critically. Alternative methodological approaches are proposed, illustrated by an example of the impact of different persistence rates on a treatment's cost-effectiveness.

RESULTS

Ten articles were selected for inclusion. These were generally scant on detail relating to how compliance/persistence was assessed and what the impact was on health outcomes. The methods used included Markov models and decision analyses. Markov models allow for persistence to be included directly in the analysis, as patients transit during each cycle. Net-benefit regression models are well suited for analyzing prospective and retrospective studies where patient-level data are available, whereas discrete event simulations have the potential to offer more flexibility.

CONCLUSIONS

Compliance and/or persistence are not included routinely in pharmacoeconomic analyses, despite their potential impact. Where compliance and/or persistence are included, a lack of methodological rigor and consistency in definitions often limits the usefulness of the analyses. The analytical techniques discussed in this article should serve as a basis for developing guidelines on appropriate methodology.

A review of health care models for coronary heart disease interventions

This article reviews models for the treatment of coronary heart disease (CHD). Whereas most of the models described were developed to assess the cost effectiveness of different treatment strategies, other models have also been used to extrapolate clinical trials, for capacity and resource planning, or to predict the future population with heart disease. In this paper we investigate the use of modelling techniques in relation to different types of health intervention, and we discuss the assumptions and limitations of these approaches. Many of the models reviewed in this paper use decision tree models for acute or short term interventions, and Markov or state transition models for chronic or long term interventions. Discrete event simulation has, however, been used for more complex whole system models, and for modelling resource-constrained interventions and operational planning. Nearly all of the studies in our review used cohort-based models rather than population based models, and therefore few models could estimate the likely total costs and benefits for a population group. Most studies used de novo purpose built models consisting of only a small number of health states. Models of the whole disease system were less common. The model descriptions were often incomplete. We recommend that the reporting of model structure, assumptions and input parameters is more explicit, to reduce the risk of biased reporting and ensure greater confidence in the model results.

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.

A pharmacoeconomic evaluation of statins in the treatment of hypercholesterolaemia in the primary care setting in Spain

BACKGROUND

Cardiovascular disease is one of the leading causes of death and it has been shown that primary prevention with the HMG-CoA reductase inhibitor (statin) lipid-lowering drugs can reduce cardiovascular events. Acquisition costs vary between statins and this may be an important consideration in the overall cost effectiveness (CE) of different options.

OBJECTIVE

To perform a CE study of the main statins used in Spain for primary prevention of cardiovascular disease in patients with high cholesterol levels [corrected]

STUDY DESIGN

The CE analysis was based on an open-label, prospective, naturalistic, randomised intervention study under usual care conditions in primary care settings in patients with high cholesterol levels (total cholesterol [TC] >240 mg/dL, low-density lipoprotein cholesterol [LDL-C] >160 mg/dL) and one or more cardiovascular risk factors. The analysis was conducted from the perspective of the Spanish National Health System; the year of costing was 2001.

PATIENTS

A total of 161 patients (49.7% males), mean age 65 +/- 10.3 years, without evidence of cardiovascular disease were included in the study. Of those, 82.1% were hypertensive, 37.1% had diabetes mellitus and 17.9% were smokers.

INTERVENTIONS

Forty-eight patients received oral atorvastatin 10 mg/day, 32 received fluvastatin 40 mg/day, 44 received simvastatin 20 mg/day and 37 patients received pravastatin 20 mg/day for 6 months.

MAIN MEASUREMENTS AND RESULTS

After 6 months, the therapeutic goals of LDL-C control, according to the recommendations of the Spanish Society of Arteriosclerosis--Consensus-2000, were reached in 62.5%, 43.8%, 45.5% and 40.5% of patients treated with atorvastatin, fluvastatin, simvastatin and pravastatin, respectively. The average CE ratio, expressed as the cost in euros (euro) per patient achieving the therapeutic goals, was euros 424.3 for atorvastatin, euros 503.5 for fluvastatin, euros 527.0 for simvastatin and euros 683.4 for pravastatin. The incremental CE ratios for atorvastatin versus fluvastatin and simvastatin were euros 238.9 and euros 149.5, respectively, per additional patient reaching therapeutic goals. Atorvastatin, fluvastatin and simvastatin all dominated pravastatin.

CONCLUSIONS

All the statins studied have been shown to be effective for reducing both TC and LDL-C levels. In this study, atorvastatin was the most efficient drug, with the best CE ratio (cost per patient reaching therapeutic goals). Atorvastatin was more effective and less costly than pravastatin, and when compared with fluvastatin or simvastatin the additional cost per additional patient achieving therapeutic goals was <euros 250.

Dyslipidemia

The major goal in treatment of patients with dyslipidemia is to decrease the short- and long-term incidence of cardiovascular events, including myocardial infarction, unstable angina, stroke, and death. A second goal in patients with severe hypertriglyceridemia is to decrease the risk of acute pancreatitis. Improvement of the lipid profile can be achieved through a combination of aggressive lifestyle modification and effective drug therapy. Treatment should be tailored to the individual patient, based on the specific lipid abnormalities, the presence or absence of pre-existing coronary artery or other atherosclerotic vascular disease, and an assessment of overall cardiovascular risk.

[Cost-effectiveness of atorvastatin against simvastatin as hypolipemic treatment in hypercholesterolemic patients in primary care]

OBJECTIVE

To perform an economics evaluation of lipid-lowering therapy with atorvastatin and simvastatin in patients with hypercholesterolemia in primary care setting.

DESIGN

Cost-effectiveness analysis (CEA) has been carried out by means of an open, random, prospective, "real world" study, with hypercholesterolemic patients (total cholesterol [TC] > 240 mg/dl and cLDL > 160 mg/dl).

PATIENTS

A total of 92 patients were included (44.8% males), with a mean age of 64.9 +/- 9.4 years old (mean +/- standard deviation). 41.4% were diabetics, 62.1% hypertensives and 16.1% smokers.

INTERVENTIONS

Patients were allocated to simvastatin 20 mg/day (44) and atorvastatin. 10 mg/day (48) for 6 months. ASSESSMENT AND MAIN RESULTS: Both therapies reduced significantly cLDL, TC and triglycerides at the end of the study. Atorvastatin reduced lipids faster than simvastatin at 3 months (p < 0.05), but significant differences could not be observed at 6 months. Atorvastatin reduced cLDL levels by 21.5 +/- 13.2% and 23.8 +/- 13.9% at 3 and 6 months, respectively, versus 16.4 +/- 14.2% and 22.8 +/- 10.8% with simvastatin. By these reductions, 54.2% of patients treated with atorvastatin and 50.0% of those allocated to simvastatin reached therapeutic goals of cLDL control. Atorvastatin 10 mg was more cost-effective than simvastatin 20 mg; 95,406 versus 101,335 pts per patient reaching therapeutic goals, respectively, which means that simvastatin need an extra cost of 24,833 pts per patient reaching therapeutic goals to be as efficient as atorvastatin. Sensitivity analysis to control for uncertainty confirmed the results of cost-effectiveness analysis.

CONCLUSIONS

Both statins were effective as lipid-lowering agents. However, atorvastatin 10 mg was more efficient than simvastatin 20 mg due to a better cost-effectiveness ratio.