Valuck Robert J, Morrato Elaine H, Dodd Sheri, Oderda Gary, Haxby Dean G, Allen Richard
University of Colorado at Denver and Health Sciences Center, School of Pharmacy, Denver, CO 80262, USA.
Curr Med Res Opin. 2007 Oct;23(10):2567-76. doi: 10.1185/030079907X233214.
To characterize healthcare costs associated with antipsychotic polypharmacy and to investigate predictors of high-cost patients.
A retrospective cohort study using Medicaid claims data from California, Nebraska, Oregon, Utah, and Wyoming evaluated 55 383 fee-for-service patients with antipsychotic prescriptions between 1998 and 2002. Polypharmacy was defined as initiating multiple antipsychotic drugs or concomitant antipsychotic therapy (>or=60 days). Healthcare costs (drug and non-drug) were summed for 365 days following index antipsychotic claim. Adjusted mean costs were compared to antipsychotic monotherapy. Logistic regression was performed to identify predictors of high-cost patients (top quintile) with regard to patient age, gender, race/ethnicity, mental disorders, hospitalization, index antipsychotic, concomitant psychotropic drugs, and polypharmacy.
The average annual prevalence of antipsychotic polypharmacy was 6%. 70-80% of total healthcare expenditures for polypharmacy patients were drug-related. Polypharmacy was associated with significantly higher drug expenditures ($1716-2079) in the year following drug initiation than monotherapy even after adjusting for case mix and index antipsychotic (p < 0.05). Differences in non-drug expenditures versus monotherapy were smaller and varied by state ranging from a $77 increase in California (p < 0.001) to a $211 savings in Utah (p = 0.02). In California, polypharmacy alone (OR = 2.69; 95% CI: 2.30-3.16) or in combination with concomitant psychotropics (OR = 6.26; 95% CI: 5.51-7.11) was associated with greater likelihood of being a high-cost patient than monotherapy.
Cost savings from limiting antipsychotic polypharmacy could be significant. Caution must be taken in ensuring reductions in polypharmacy do not lead to unintended consequences or shift care to more costly alternatives. Study limitations, including the known shortcomings of claims data and differences across state Medicaid programs, should be considered when interpreting the results of this or any multi-state study.
描述与抗精神病药物联合使用相关的医疗费用，并调查高费用患者的预测因素。
一项回顾性队列研究使用了来自加利福尼亚州、内布拉斯加州、俄勒冈州、犹他州和怀俄明州的医疗补助索赔数据，评估了1998年至2002年间55383名接受抗精神病药物处方的按服务收费患者。联合用药被定义为开始使用多种抗精神病药物或同时进行抗精神病治疗（≥60天）。在首次抗精神病药物索赔后的365天内汇总医疗费用（药物和非药物）。将调整后的平均费用与抗精神病药物单一疗法进行比较。进行逻辑回归以确定高费用患者（最高五分位数）在患者年龄、性别、种族/民族、精神障碍、住院情况、首次抗精神病药物、同时使用的精神药物和联合用药方面的预测因素。
抗精神病药物联合使用的年平均患病率为6%。联合用药患者的总医疗支出中有70 - 80%与药物相关。即使在调整病例组合和首次抗精神病药物后，联合用药在开始用药后的一年中与比单一疗法显著更高的药物支出（1716 - 2079美元）相关（p < 0.05）。与单一疗法相比，非药物支出的差异较小，且因州而异，从加利福尼亚州增加77美元（p < 0.001）到犹他州节省211美元（p = 0.02）。在加利福尼亚州，单独联合用药（OR = 2.69；95% CI：2.30 - 3.16）或与同时使用的精神药物联合使用（OR = 6.26；95% CI：5.51 - 7.11）比单一疗法更有可能成为高费用患者。
限制抗精神病药物联合使用可能会节省大量成本。必须谨慎确保减少联合用药不会导致意外后果或将护理转向成本更高的替代方案。在解释本研究或任何多州研究的结果时，应考虑研究局限性，包括索赔数据的已知缺点和各州医疗补助计划的差异。
