Pharmacy Service, Galdakao-Usansolo Hospital, Barrio Labeaga s/n, Galdakao, Basque Country, Spain.
Gen Hosp Psychiatry. 2012 Jul-Aug;34(4):423-32. doi: 10.1016/j.genhosppsych.2012.01.019. Epub 2012 Mar 27.
The aim of our study was to assess the antipsychotic polypharmacy (APP) prevalence in a psychiatric hospital and to find the supporting evidence for the 10 most prescribed two-drug combinations. Secondarily, how many included clozapine, prevalence in the elderly, high dosage and clinically relevant interactions were also assessed.
Clinicodemographic and computerized prescription data on 29th March 2011 were collected. High dosage was defined as more than 1000 mg of chlorpromazine equivalents (CPZeqs). A t test for unpaired measures was applied to compare means of dosage (CPZeq) and age among patients on APP vs. monotherapy. The χ(2) test was applied to compare proportions of patients on a high dose on APP vs. monotherapy. GraphPad Prism 5 software was used to perform statistical analysis.
From 201 patients admitted on 29th March, 172 had any antipsychotic prescription. APP prevalence was 47.1%, corresponding almost to 24% of elderly patients. Quetiapine was the drug most prescribed in combination, achieving a prevalence rate of 56.8%. Clozapine was not included in 67% of all combinations. Supporting evidence for two-drug combinations was only found for 6 of the 10 most prescribed. Relevant interactions were found in 12 patients on APP. The mean CPZeq dose and percentage of patients on high dosage were significantly higher in the APP than in the monotherapy group (1162±776.1 mg vs. 455.4±369.3 mg; 54% vs. 9%, respectively; P<.0001).
Our study shows that APP was being considered earlier in the management plan than what guidelines recommend. This practice was associated with higher total antipsychotic doses. Until further clinical trials are available, a wise APP practice will require a thoughtful choice of products guided by patient's prior history and interaction liability, a proper consent by the patients or their representatives and a careful monitoring of clinical outcomes and emerging side effects in order to avoid indefinite administration of ineffective and potentially harmful combinations.
我们的研究旨在评估一家精神病院的抗精神病药联合用药（APP）的流行程度，并为最常开的两种药物组合找到支持证据。其次，我们还评估了包含氯氮平的病例数量、老年人中的流行程度、高剂量和临床相关的相互作用。
我们收集了 2011 年 3 月 29 日的临床和计算机化处方数据。高剂量定义为超过 1000 毫克氯丙嗪当量（CPZeqs）。采用配对样本 t 检验比较 APP 与单药治疗患者的剂量（CPZeq）和年龄的均值。采用卡方检验比较 APP 与单药治疗患者高剂量的比例。GraphPad Prism 5 软件用于进行统计分析。
在 29 日收治的 201 名患者中，有 172 人有任何抗精神病药物处方。APP 的流行率为 47.1%，几乎相当于 24%的老年患者。喹硫平是最常联合使用的药物，其流行率为 56.8%。在所有联合用药中，氯氮平未被纳入 67%。仅为 10 种最常开的药物组合中的 6 种找到了两药组合的支持证据。在 APP 患者中发现了 12 例相关的相互作用。APP 组的 CPZeq 剂量均值和高剂量患者比例明显高于单药治疗组（1162±776.1 mg 比 455.4±369.3 mg；54%比 9%；P<.0001）。
我们的研究表明，APP 比指南建议的更早被纳入管理计划。这种做法与更高的总抗精神病药物剂量有关。在进一步的临床试验可用之前，明智的 APP 实践将需要根据患者的既往病史和相互作用风险、患者或其代表的适当同意以及仔细监测临床结果和新出现的副作用，来明智地选择产品，以避免对无效和潜在有害的联合用药进行无限期的使用。
