Henry J A, Rivas C A
St Mary's Hospital, London, England.
Pharmacoeconomics. 1997 Jun;11(6):515-37. doi: 10.2165/00019053-199711060-00002.
Cost-effectiveness studies are a useful tool in drug-choice decisions. They are appropriate when alternative therapies have different levels of effectiveness, as with antidepressants. The calculation of cost effectiveness is similar to that used by some authors to determine whether a drug should be included in a formulary, so it clearly has immediate practical application and potential acceptability. However, the actual acceptability of cost-effectiveness studies has been hampered by a lack of conformity over study objectives, methodology and use of available data, and this significantly affects results. Studies that focus on the same location and setting, and conducted at the same time, frequently provide different results in their conclusions, depending on the assumptions and viewpoints, and the effects of sampling error. For example, dosage can affect purchase price calculations, but also compliance and efficacy, which are important considerations. Moreover, conclusions based on cost disadvantages of new drugs are not appropriate for planning for the future, since a drug's market price tends to fall with time and increasing demand. Appropriate use of outcome measures is important, and treatment failures, as well as successes, should be considered. Cost-effectiveness analysis has been used to demonstrate an important point: even when the appropriate use of antidepressants and specialty care increases medical costs, it improves value for money. A variety of drugs for one indication should be available to the prescriber, as the most cost-effective one may differ between patient subpopulations. Many costs of morbidity, adverse effects and secondary effects of antidepressants remain to be properly quantified, but are likely to have an important influence on cost effectiveness. These costs are likely to be higher for tricyclic antidepressants than the newer reversible inhibitors of monoamine oxidase and selective serotonin (5-hydroxytryptamine; 5-HT) reuptake inhibitors. Costing in some areas of health is relatively straightforward. Depression is among the most difficult areas to cost because of its gradation in severity, its chronic and recurrent nature, and its subtle effects on working capacity. Quantification of differences resulting from the use of different drugs has many pitfalls. Until now, each cost analysis of depression has differed from the last, and most have placed excessive reliance on poorly substantiated and hypothetical assumptions. More in-depth studies are required to define the most cost-effective policies for recommendation to healthcare decision-makers and antidepressant drug prescribers. Compliance, adverse effects, and safety in overdose are important factors. The impact of indirect costs also needs to be addressed.
成本效益研究是药物选择决策中的一种有用工具。当替代疗法具有不同的疗效水平时，如抗抑郁药，这种方法就很适用。成本效益的计算与一些作者用于确定一种药物是否应纳入处方集的方法类似，因此它显然具有直接的实际应用价值和潜在的可接受性。然而，成本效益研究的实际可接受性受到研究目标、方法和可用数据使用方面缺乏一致性的阻碍，这显著影响了研究结果。在相同地点和环境、同时进行的研究，由于假设和观点以及抽样误差的影响，其结论往往会得出不同的结果。例如，剂量会影响购买价格的计算，但也会影响依从性和疗效，而这些都是需要考虑的重要因素。此外，基于新药成本劣势得出的结论并不适合未来规划，因为药物的市场价格往往会随着时间和需求的增加而下降。正确使用结果指标很重要，治疗失败和成功都应予以考虑。成本效益分析已被用于证明一个重要观点：即使合理使用抗抑郁药和专科护理会增加医疗成本，但它能提高性价比。对于一种适应症，应该为开处方者提供多种药物，因为最具成本效益的药物可能因患者亚群而异。抗抑郁药的许多发病成本、不良反应和继发效应仍有待恰当量化，但可能会对成本效益产生重要影响。三环类抗抑郁药的这些成本可能高于新型可逆单胺氧化酶抑制剂和选择性5-羟色胺再摄取抑制剂。在某些健康领域进行成本核算相对简单。由于抑郁症严重程度的分级、其慢性和复发性本质以及对工作能力的微妙影响，抑郁症是最难进行成本核算的领域之一。量化使用不同药物所产生的差异存在许多陷阱。到目前为止，每次抑郁症成本分析都与上一次不同，而且大多数分析过度依赖缺乏充分依据的假设。需要进行更深入的研究，以确定最具成本效益的政策，供医疗保健决策者和抗抑郁药开处方者参考。依从性、不良反应和过量用药时的安全性都是重要因素。间接成本的影响也需要加以解决。
