Insights on the natural history of problem drug user (PDU) offending

背景问题药物使用（PDU）被认为是造成非常高的社会和经济成本的原因-英格兰和威尔士A类药物使用的总成本估计每年超过150亿英镑[3]，PDU占了大部分成本。估计的成本如此之高，是因为犯罪被认为是由PDU引起的-有人认为，所有记录在案的掠夺性犯罪中有一半以上与毒品有关[31]。毒品与犯罪之间的联系在过去已经通过对被捕者的研究[32]和对监狱中的人的研究[33]进行了探索，以估计这些罪犯群体的毒品使用水平和类型。在这些人的自然历史中，吸毒和犯罪之间存在联系的最简单的论点是，吸毒者开始犯罪是为了支付毒品。但是，研究也指出，犯罪活动往往发生在PDU开始之前[9，34]。因此，毒品犯罪联系的方向并不总是明确的。此外，有时根本没有毒品犯罪联系-并非所有PDU都是罪犯，也并非所有罪犯都是PDU [3，33]。提议的研究。可能有许多不同的途径可以描述PDU和冒犯的自然历史。我们将审查已经就毒品与犯罪之间的联系以及毒品使用/犯罪途径的性质进行的研究。然后，我们将使用已收集的数据用于管理目的，并匿名链接有关个人的信息。这将为我们提供大量人的犯罪历史数据，我们将利用这些数据来探索他们通过PDU的自然历史，并以比以前更大的规模犯罪。我们将寻找犯罪的特点，如发病年龄，类型和频率，这是不同的吸毒前的PDUs和非PDUs。我们将进一步研究人们开始PDU后是否会发生令人不快的变化，以及是否有可能改变（缓和或调解）这些关系的因素（例如，开始使用药物的年龄）。我们认为这是非常重要的工作，因为尽管所有的公共资金都花在试图打破毒品犯罪联系上，但没有太多关于这种联系性质的确凿证据。我们的研究将导致更好地了解路由到PDU和违规。这可能导致早期识别和干预那些可能继续发展PDU的罪犯，使其更容易找到并向参与犯罪的PDU或有可能成为PDU的罪犯提供帮助。例如，研究可能会查明犯罪类型或犯罪模式，从而预测PDU的开始。针对具有这种犯罪特征的人进行量身定制的干预可以中断从犯罪到建立PDU的途径，从而防止对个人造成重大的负面健康后果，并降低与毒品相关犯罪相关的社会成本。这项工作也是独一无二的--将现有的数据集联系起来来研究这个特殊的问题，在成瘾研究领域从未如此大规模地进行过。

Background. Problem drug use (PDU) is thought to be the cause of a very high level of social and economic costs - the total costs of Class A drug use in England and Wales have been estimated to be over £15 billion per year [3] and PDU accounts for most of this cost. The estimated costs are so high because of the crime that is assumed to be caused by PDU - it has been suggested that well over a half of all recorded acquisitive crime is drug-related [31]. The drug-crime link has been explored in the past by research with people following arrest [32] and work with people in prison [33] to estimate levels, and types, of drug use in these groups of offenders. The simplest argument for the link between drug use and offending in the natural histories of these individuals is that drug users start to commit crime in order to pay for drugs. But, research also points to criminal activity often happening before PDU starts [9,34]. So, the direction of the drugs-crime link is not always clear. In addition, sometimes there is no drugs-crime link at all - not all PDUs are offenders and not all offenders are PDUs [3,33]. Proposed Research. There are likely to be a number of different pathways that could describe the natural history of PDU and offending. We will review research done already on the drug-crime link and on the nature of drug use/ offending pathways. Then, we will use data that have been collected already for administrative purposes and, anonymously, link information about individuals. This will give us data about the crime histories of a very large number of people, which we will use to explore the natural history of their pathways through PDU and offending on a much larger scale than has been previously possible. We will look for characteristics of offending, such as age at onset, type and frequency, which are different for PDUs prior to drug use and non-PDUs. We will further look at whether offending changes after people start PDU, and whether there are factors (for example, the age when drug use started) that may change (moderate or mediate) these relationships. We think this is very important work to do because, despite all the public money that is spent on trying to break the drugs-crime link, there is not much hard evidence about the nature of this link. Our research will lead to a much greater understanding of routes into PDU and offending. This could lead to early identification of, and intervention with, those offenders likely to go on to develop PDU, making it easier to find, and offer help, to PDUs who are involved in crime, or criminals who are at risk of becoming PDUs. For example, the research may pinpoint types of crime or patterns of offending which predict the start of PDU. Tailored intervention targeted at people with this offending profile could interrupt the pathway from crime to established PDU, thereby preventing significant negative health outcomes for the individual and reducing the very high costs to society associated with drug-related crime. This work is also unique - linking existing datasets to look at this particular problem has never been done before on such a large scale in the field of addiction research.