Background

Being recently released from prison or discharged from hospital, or being dispensed opioids, benzodiazepines, or antipsychotics have been associated with an increased risk of fatal drug overdose. This study aimed to examine the association between these periods and non-fatal drug overdose using a within-person design.

Methods

In this self-controlled case series, we used data from the provincial health insurance client roster to identify a 20% random sample of residents (aged ≥10 years) in British Columbia, Canada between Jan 1, 2015, and Dec 31, 2017 (n=921 346). Individuals aged younger than 10 years as of Jan 1, 2015, or who did not have their sex recorded in the client roster were excluded. We used linked provincial health and correctional records to identify a cohort of individuals who had a non-fatal overdose resulting in medical care during this time period, and key exposures, including periods of incarceration, admission to hospital, emergency department care, and supply of medications for opioid use disorder (MOUD), opioids for pain (unrelated to MOUD), benzodiazepines, and antipsychotics. Using a self-controlled case series, we examined the association between the time periods during and after each of these exposures and the incidence of non-fatal overdose with case-only, conditional Poisson regression analysis. Sensitivity analyses included recurrent overdoses and pre-exposure risk periods.

Findings

We identified 4149 individuals who had a non-fatal overdose in 2015–17. Compared with unexposed periods (ie, all follow-up time that was not part of a designated risk period for each exposure), the incidence of non-fatal overdose was higher on the day of admission to prison (adjusted incidence rate ratio [aIRR] 2·76 [95% CI 1·51–5·04]), at 1–2 weeks (2·92 [2·37–3·61]), and 3–4 weeks (1·34 [1·01–1·78]) after release from prison, 1–2 weeks after discharge from hospital (1·35 [1·11–1·63]), when being dispensed opioids for pain (after ≥4 weeks) or benzodiazepines (entire use period), and from 3 weeks after discontinuing antipsychotics. The incidence of non-fatal overdose was reduced during use of MOUD (aIRRs ranging from 0·33 [0·26–0·42] to 0·41 [0·25–0·67]) and when in prison (0·12 [0·08–0·19]).

Interpretation

Expanding access to and increasing support for stable and long-term medication for the management of opioid use disorder, improving continuity of care when transitioning between service systems, and ensuring safe prescribing and medication monitoring processes for medications that reduce respiratory function (eg, benzodiazepines) could decrease the incidence of non-fatal overdose.

Funding

Murdoch Children's Research Institute and National Health and Medical Research Council.

中文翻译：

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非致命药物过量风险改变的时期：一个自我控制的病例系列

背景

最近从监狱释放或出院，或分发阿片类药物，苯二氮卓类药物或抗精神病药与致命药物过量的风险增加相关。这项研究旨在通过个人设计检查这些时期与非致命药物过量之间的关联。

方法

在这个自我控制的案例系列中，我们使用了来自省健康保险客户花名册的数据，确定了2015年1月1日至2017年12月31日之间加拿大不列颠哥伦比亚省20％（≥10岁）居民的随机样本（ n = 921 346）。截至2015年1月1日，年龄在10岁以下或未在客户名册中记录其性别的个人被排除在外。我们使用了相关的省级健康和矫正记录来识别在此期间非致命性过量用药并导致医疗护理的人群，以及关键暴露，包括监禁期，入院时间，急诊科护理和医疗服务的供应量。阿片类药物使用障碍（MOUD）的药物，阿片类药物的疼痛（与MOUD无关），苯二氮卓类药物和抗精神病药。使用自控案例系列，我们通过仅病例的条件性Poisson回归分析检查了每次接触期间和之后的时间段与非致命过量发生率之间的关联。敏感性分析包括经常性用药过量和暴露前风险期。

发现

我们确定了4149例在2015-17年度非致命性用药过量的人。与未暴露期相比（即，每次暴露均不属于指定风险期的所有随访时间），入狱当日非致命性用药过量的发生率较高（调整后发生率[aIRR] 2·76 [95％CI 1·51-5·04]，1-2周（2·92 [2·37-3·61]）和3-4周（1·34 [1·01] –1·78]）出狱后，出院后1–2周（1·35 [1·11–1·63]），为疼痛而分配阿片类药物（≥4周后）或苯二氮卓类药物（整个使用期限），以及从停用抗精神病药后的3周开始。在使用MOUD期间（aIRR范围从0·33 [0·26-0.42]到0·41 [0·25-0·67]）和在监狱服刑期间（0· 12 [0·08–0·19]）。

解释

扩大获得稳定和长期药物以治疗阿片类药物使用障碍的机会并增加支持，在服务系统之间转换时改善护理的连续性，并确保对降低呼吸功能的药物（例如苯二氮卓类药物）进行安全的处方和药物监测过程可以降低非致死性用药过量的发生率。

资金

默多克儿童研究所和国家卫生与医学研究理事会。