Chen Lei, McCombs Jeffrey S, Park Jinhee
Department of Pharmaceutical Economics and Policy, School of Pharmacy, University of Southern California, Los Angeles, CA, USA.
Value Health. 2008 May-Jun;11(3):487-96. doi: 10.1111/j.1524-4733.2007.00262.x.
Duration of drug therapy is a key measure of drug effectiveness in schizophrenia. The Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE) trial found that only olanzapine achieved a longer time to all-cause-discontinuation (TTAD) than a standard therapy comparator. This study compares the TTAD achieved when using alternative antipsychotics to treat patients with schizophrenia in real-world practice settings.
A total of 219,504 episodes of antipsychotic therapy initiated in the years 2000 to 2002 were identified using data from the California Medicaid (Medi-Cal) program. To capture the full range of treatment scenarios facing clinicians, four episode types were included: restarting therapy using the drug used in the preceding episode; restarting therapy using a different medication (delayed switches); switching therapy without a break in therapy; and augmentation. TTAD and changes in therapy were analyzed using ordinary least squares and logistic regressions and Cox proportional hazards models.
Atypical antipsychotics consistently achieved longer TTAD and reduced switching rates relative to conventional antipsychotics. Differences in TTAD favoring atypical antipsychotics were 13 to 15 days in restart episodes; 28 to 36 days for delayed switching episodes; 41 to 52 days in switching episodes; and 59 to 63 days for augmentation (P < 0.0001 for all estimates). Differences between the atypical antipsychotics were smaller than reported in other studies and may not be clinically significant.
This study confirms two results from the CATIE study: Patients with schizophrenia frequently do not achieve stable, long-term drug therapy regardless of the specific drug used, and olanzapine achieved longer TTAD than conventional drugs. However, this study also found that patients treated with risperidone and quetiapine also achieved longer TTAD than patients treated with conventional antipsychotics.
药物治疗时长是衡量精神分裂症药物疗效的关键指标。临床抗精神病药物干预有效性试验（CATIE）发现，只有奥氮平的全因停药时间（TTAD）比标准治疗对照药更长。本研究比较了在现实临床环境中使用其他抗精神病药物治疗精神分裂症患者时的TTAD。
利用加利福尼亚医疗补助（Medi-Cal）项目的数据，确定了2000年至2002年启动的总共219,504次抗精神病药物治疗疗程。为涵盖临床医生面临的所有治疗场景，纳入了四种疗程类型：使用上一疗程所用药物重新开始治疗；使用不同药物重新开始治疗（延迟换药）；不间断治疗直接换药；以及增效治疗。使用普通最小二乘法、逻辑回归和Cox比例风险模型分析TTAD和治疗变化情况。
与传统抗精神病药物相比，非典型抗精神病药物始终具有更长的TTAD并降低了换药率。在重新开始治疗的疗程中，非典型抗精神病药物在TTAD上的优势为13至15天；延迟换药疗程为28至36天；直接换药疗程为41至52天；增效治疗疗程为59至63天（所有估计值P<0.0001）。非典型抗精神病药物之间的差异小于其他研究报告的差异，可能无临床意义。
本研究证实了CATIE研究的两个结果：无论使用何种具体药物，精神分裂症患者通常都无法实现稳定、长期的药物治疗，且奥氮平的TTAD比传统药物更长。然而，本研究还发现，使用利培酮和喹硫平治疗的患者的TTAD也比使用传统抗精神病药物治疗的患者更长。
