Yu Wei, Ren Xinhua S, Lee Austin F, Herz Lawrence, Huang Yu-Hui, Kazis Lewis E
Health Economics Resource Center, VA Palo Alto Health Care System, Menlo Park, California 94025, USA.
Pharmacoeconomics. 2006;24(12):1233-48. doi: 10.2165/00019053-200624120-00007.
Olanzapine and risperidone are two commonly prescribed atypical antipsychotics for schizophrenia. Prior studies have shown inconsistent results in terms of advantage in cost saving in prescribing these agents. Our preliminary analysis showed that a small percentage of intensive healthcare utilizers had substantial impact on healthcare costs. This study analysed the cost effects of olanzapine and risperidone among those who had intensive utilisation of medical care prior to drug initiation, and the relationship between the choice of the two drugs and patients' co-morbid condition.
We retrospectively investigated patients first treated with either risperidone or olanzapine between 1 April 1999 and 31 March 2000. According to patients' medication history during the 6 months prior to initial prescription of a study medication we categorised patients into three groups: (i) not receiving olanzapine or risperidone; (ii) not receiving any atypical antipsychotic agent; or (iii) not receiving any antipsychotic agent. We then compared the difference in cost saving by type of care in the 10% most expensive patients through bivariate and multivariate analyses. Based on the records of 18 499 patients with schizophrenia prescribed either olanzapine or risperidone between 1 April 1999 and 31 March 2000 we defined intensive users of healthcare as those who incurred an annual total cost in the top tenth percentile. We measured co-morbidity by number of diseases, and healthcare costs ($US, 1998-2001 values) in the year prior and the year after treatment initiation in six categories of care (inpatient medical/surgical, inpatient psychiatric care, other inpatient, outpatient psychiatric care, other outpatient and outpatient pharmacy).
The top 10% most expensive patients accounted for about half of the total cost of the entire cohort and had nearly a 40% cost reduction for the year after treatment initiation versus the prior year, while the entire cohort increased cost between 2% and 12%. Compared with those prescribed olanzapine, patients prescribed risperidone had more medical co-morbidities, higher inpatient medical/surgical costs and lower psychiatric costs. Patients taking olanzapine had greater cost reduction in inpatient psychiatric care, whereas those taking risperidone had greater reduction in inpatient medical/surgical care.
Among the top 10% most expensive patients, olanzapine and risperidone treatments were associated with comparable cost reductions in inpatient care. The choice of agent was associated with patients' co-morbid condition and was correlated with cost reduction in inpatient medical/surgical or psychiatric care.
奥氮平和利培酮是两种常用于治疗精神分裂症的非典型抗精神病药物。先前的研究表明，在使用这些药物节省成本方面，结果并不一致。我们的初步分析显示，一小部分频繁使用医疗服务者对医疗成本有重大影响。本研究分析了在开始用药前频繁使用医疗服务者中奥氮平和利培酮的成本效果，以及这两种药物的选择与患者共病情况之间的关系。
我们回顾性调查了1999年4月1日至2000年3月31日期间首次接受利培酮或奥氮平治疗的患者。根据患者在研究药物初始处方前6个月的用药史，我们将患者分为三组：（i）未接受奥氮平或利培酮；（ii）未接受任何非典型抗精神病药物；或（iii）未接受任何抗精神病药物。然后，我们通过双变量和多变量分析比较了10%最昂贵患者中不同类型医疗服务的成本节省差异。基于1999年4月1日至2000年3月31日期间18499例开具奥氮平或利培酮的精神分裂症患者的记录，我们将频繁使用医疗服务者定义为年度总成本处于前十分位数的患者。我们通过疾病数量衡量共病情况，并在治疗开始前一年和开始后一年的六类医疗服务（住院医疗/外科、住院精神科护理、其他住院、门诊精神科护理、其他门诊和门诊药房）中测量医疗成本（美元，1998 - 2001年数值）。
最昂贵的10%患者占整个队列总成本的约一半，与治疗前一年相比，治疗开始后一年成本降低了近40%，而整个队列的成本增加了2%至12%。与开具奥氮平的患者相比，开具利培酮的患者有更多的医疗共病，住院医疗/外科成本更高，精神科成本更低。服用奥氮平的患者在住院精神科护理方面成本降低幅度更大，而服用利培酮的患者在住院医疗/外科护理方面成本降低幅度更大。
在最昂贵的10%患者中，奥氮平和利培酮治疗在住院护理方面的成本降低效果相当。药物的选择与患者的共病情况有关，并且与住院医疗/外科或精神科护理的成本降低相关。
