Morrato Elaine H, Dodd Sheri, Oderda Gary, Haxby Dean G, Allen Richard, Valuck Robert J
Pharmaceutical Outcomes Research Program, Department of Clinical Pharmacy, School of Pharmacy, University of Colorado Health Sciences Center, Denver, Colorado 80262, USA.
Clin Ther. 2007 Jan;29(1):183-95. doi: 10.1016/j.clinthera.2007.01.002.
This study was conducted to estimate the prevalence of antipsychotic polypharmacy among fee-for service state Medicaid beneficiaries initiating antipsychotic drug therapy and to investigate psychiatric and demographic predictors of such polypharmacy.
This was a retrospective cohort study employing Medicaid claims data from California, Nebraska, Oregon, Utah, and Wyoming for patients who filled >1 antipsychotic prescription between 1998 and 2003 and who were continuously eligible for benefits from 180 days before to 1 year after the index antipsychotic claim. Antipsychotic Polypharmacy was defined as initiation of multiple antipsychotic medications or at least 60 consecutive days of concomitant antipsychotic medication overlapping the index antipsychotic prescription at any time during the 365 days after the index drug claim. Primary and secondary diagnosis codes (International Classification of Diseases, Ninth Revision, Clinical Modification) were used to identify patients with mental disorders and mental health-related hospitalizations. Multivariate logistic regression, with adjustment for sex, age, race/ethnicity, state, mental health diagnoses, hospitalization, year, and type of index antipsychotic, was performed to identify predictors of polypharmacy. A multivariate Cox proportional hazards model was used to compare the cumulative incidence of polypharmacy by index antipsychotic drug.
The study cohort consisted of 55,481 individuals with > or =1 prescription claim for an antipsychotic drug. The mean prevalence of long-term antipsychotic polypharmacy in the year after initiating antipsychotic medication was 6.4%. Approximately half of those with polypharmacy were started on multiple antipsychotic drugs and half were started on monotherapy but received > or =2 antipsychotic drugs concomitantly in the year after drug initiation. Among the stronger predictors of polypharmacy were a diagnosis of schizophrenia (odds ratio [OR] = 2.95; 95% Cl, 2.43-3.58), recent mental health hospitalization (OR = 1.17; 95% Cl, 1.02-1.33), and the number of mental health diagnoses (OR = 1.07 per diagnosis; 95% CI, 1.06-1.08). Polypharmacy was more likely among male than female patients (OR = 1.26; 95% Cl, 114-1.39) and among those between the ages of 18 and 24 years. The cumulative incidence of polypharmacy was greater among patients initiating clozapine compared with those initiating other antipsychotics (P < 0.001).
In these fee-for-service Medicaid beneficiaries from 5 states, the prevalence of chronic antipsychotic polypharmacy was low in the year after the initiation of therapy. Polypharmacy was more common in patients with indicators of more severe mental illness.
本研究旨在估算在接受按服务付费的州医疗补助计划的受益人群中，开始抗精神病药物治疗时联用多种抗精神病药物的比例，并探究此类联用的精神科及人口统计学预测因素。
这是一项回顾性队列研究，利用加利福尼亚州、内布拉斯加州、俄勒冈州、犹他州和怀俄明州的医疗补助计划理赔数据，研究对象为在1998年至2003年间开具过1份以上抗精神病药物处方，且在索引抗精神病药物理赔日期前180天至理赔后1年持续符合受益条件的患者。联用多种抗精神病药物的定义为：在索引药物理赔后的365天内，开始使用多种抗精神病药物，或在任何时间至少连续60天同时使用与索引抗精神病药物处方重叠的抗精神病药物。使用主要和次要诊断编码（国际疾病分类第九版，临床修订本）来识别患有精神障碍和与心理健康相关住院治疗的患者。进行多变量逻辑回归分析，对性别、年龄、种族/族裔、州、心理健康诊断、住院治疗、年份和索引抗精神病药物类型进行调整，以确定联用多种抗精神病药物的预测因素。使用多变量Cox比例风险模型比较不同索引抗精神病药物联用多种抗精神病药物的累积发生率。
研究队列包括55481名开具过至少1份抗精神病药物处方的个体。开始抗精神病药物治疗后一年中长期联用多种抗精神病药物的平均比例为6.4%。联用多种抗精神病药物的患者中，约一半开始时使用多种抗精神病药物，另一半开始时接受单一疗法，但在开始用药后的一年中同时接受了至少2种抗精神病药物。联用多种抗精神病药物的较强预测因素包括精神分裂症诊断（优势比[OR]=2.95；95%可信区间[CI]，2.43-3.58）、近期心理健康住院治疗（OR=1.17；95%CI，1.02-1.33）以及心理健康诊断的数量（每个诊断的OR=1.07；95%CI，1.06-1.08）。男性患者比女性患者更易联用多种抗精神病药物（OR=1.26；95%CI，1.14-1.39），18至24岁的患者也是如此。与开始使用其他抗精神病药物的患者相比，开始使用氯氮平的患者联用多种抗精神病药物的累积发生率更高（P<0.001）。
在这5个州接受按服务付费的医疗补助计划的受益人群中，治疗开始后一年慢性联用多种抗精神病药物的比例较低。联用多种抗精神病药物在患有更严重精神疾病指标的患者中更为常见。
