Only a few studies have investigated changes in the dose of long-acting injectable second-generation antipsychotics (LAI-SGAs) over the long term in the maintenance treatment of schizophrenia. In this retrospective cohort study, we examined longitudinal changes in antipsychotic dose over a 3-year period in patients with schizophrenia who had been taking LAI-SGAs for at least 1 year. We compared the total daily chlorpromazine equivalent dose of antipsychotics at 12, 24 and 36 months with the baseline dose at 3 months after initiation of LAI-SGAs. We also performed multiple regression analysis to explore factors associated with change in total daily dose 12 months after treatment initiation. A total of 154 patients fulfilled the inclusion criteria. There was no significant difference in total daily antipsychotic dose between 3 months and 12, 24 or 36 months after treatment initiation. Total daily dose was increased in 43 (27.9%), 31 (34.8%) and 22 patients (36.7%) at 12, 24 and 36 months, respectively. Age and total antipsychotic dose at 3 months were significantly negatively associated with change in total daily dose. Antipsychotic dose was basically unchanged during long-term treatment in patients treated with LAI-SGAs in the maintenance phase, although there was an increase in some patients.

中文翻译：

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长效注射第二代抗精神病药治疗的患者抗精神病药剂量的纵向变化。

长期以来，只有少数研究调查了长效可注射第二代抗精神病药（LAI-SGAs）在精神分裂症维持治疗中的剂量变化。在这项回顾性队列研究中，我们检查了服用LAI-SGA至少1年的精神分裂症患者在3年期间抗精神病药物剂量的纵向变化。我们比较了在开始LAI-SGA后3、12、24和36个月抗精神病药物的每日总氯丙嗪当量剂量与基线剂量在3个月时的基线剂量。我们还进行了多元回归分析，以探讨与治疗开始后12个月每日总剂量变化相关的因素。共有154位患者符合纳入标准。3个月至12个月期间，每日总抗精神病药物剂量无显着差异。治疗开始后24或36个月。在12、24和36个月时，每日总剂量分别增加了43名（27.9％），31名（34.8％）和22名患者（36.7％）。3个月时的年龄和总抗精神病剂量与每日总剂量的变化显着负相关。在维持期接受LAI-SGA治疗的患者，长期治疗期间抗精神病药物的剂量基本没有变化，尽管有些患者有所增加。