Quantifying Exposure to Illicit Drugs & Psychosocial Stress in Real Time

对吸毒和社会心理压力的评估是复杂的，因为它们往往都是短暂的，很难准确回忆。由于因果联系的复杂性和构成环境的难以捉摸的性质，对它们彼此之间的因果联系以及它们的遗传和环境决定因素的评估是复杂的。在这个项目中，我们通过生态瞬间评估(EMA)近乎实时地评估药物使用和心理社会压力，在EMA中，参与者使用手持电子日记记录事件发生时，并根据全天随机定时的提示报告最近或正在发生的事件。我们还通过让参与者携带全球定位系统(GPS)设备，以几米的空间分辨率跟踪他们的下落，从而保持对报告事件发生地点的实时记录。这些数据在一种我们称为地理瞬时评估(GMA)的方法中被集体使用，下面将进一步描述。 对我国正在接受治疗的多药吸毒者人群的EMA数据分析表明，负面情绪(压力)、庆祝状态和药物线索与随后的可卡因使用有关。接触合法药物，如烟草，也与可卡因的使用和对可卡因的渴望密切相关。在特定时刻吸烟的可能性随着当前对可卡因的渴望(或对海洛因和可卡因的双重渴望)的严重程度而线性增加。在使用可卡因(或可卡因和海洛因)期间吸烟的可能性更大。在我们控制了人口统计变量、地点和情绪后，这种关联仍然显著。这些发现对压力和非法药物的暴露有影响，并将被纳入我们的风险暴露评估算法。 我们还调查了尿液验证的可卡因使用和戒除期间的伴随因素。在队列设计中，112名服用美沙酮的可卡因和海洛因滥用门诊患者的志愿者样本在掌上电脑上提供了10,781人日的EMA数据。EMA对有关当前地点、活动、同伴、情绪和最近暴露于可能的药物使用触发因素的问题的回答在使用和戒毒期间进行了比较。吸食可卡因的时间与闲散、孤独、情绪低落的下午有关，但出乎意料的是，也与清晨或深夜工作的可能性更大相关。在同一样本的先前分析中，可卡因的全天伴随使用往往与急性使用不同。在禁欲期间，负面情绪的几项指标有所增加。门诊患者几周的可卡因使用和戒除与不同的情绪和行为模式有关；这里报告的详细的每小时数据应该有助于为旨在改变日常活动的治疗干预提供信息。 这项研究的数据也被用来实时地和在吸毒者的日常生活环境中调查渴望与吸毒之间的关系。渴望通常被认为会导致持续的药物使用和复发，这是成瘾研究的一个主要焦点。然而，它与毒品使用的关系还没有得到充分的记录。参与者在进行日常活动时，随机地对他们的渴望和情绪进行评级(每天两到五次，由电子日记提示)。他们还在每次使用可卡因时启动了电子日记记录。药物使用通过每周三次的尿检进行监测。在尿液验证的可卡因使用期间，可卡因渴求的评级全天都在增加，并且高于尿液验证的戒毒期间。在使用可卡因之前的五个小时内，对可卡因的渴望程度显著增加。这些模式在海洛因渴望或情绪(例如，感到快乐或无聊)的评级中看不到。在使用者的正常环境中，可卡因的渴望与可卡因的使用密切相关。我们的发现为这段在一些理论上受到严重质疑的关系提供了以前无法获得的支持。 扩大了环境因素的定义，我们使用包含连续地理位置跟踪的GMA来评估邻里水平的影响，这些影响是根据专门开发的指数衡量的，例如邻里心理社会危害指数(NPH)，该指数基于从公共来源获得的独立于自我报告的客观统计数据，以及NIfETy，基于训练有素的观察员的客观环境评级。为了进行比较，我们还通过回顾访谈和生物样本(尿液)评估药物暴露，并通过生理措施(恒定负荷)评估压力。预计结果将是一套可现场部署的最先进工具，对于未来影响药物使用和压力的基因-环境相互作用的研究不可或缺。 我们已经完成了初步初步研究，以确定适当的全球定位系统设备和地点抽样战略，并完成了一项有29名参与者参加的发展试验，他们携带电子日记和全球定位系统约100天。我们正在分析实时定位数据，并将其与EMA数据和尿液药物筛查结果结合起来，以完成GMA试点研究。作为风险暴露算法开发的一部分，我们还一直在基于公开可用的数据库和NIfETy数据开发环境风险衡量标准。我们目前正在进行一项更大规模的试验，其中包括额外的压力措施。

Assessment of exposure to drug use and psychosocial stress is complicated by the fact that each is often transient and difficult to recall accurately. Assessment of their causal connections with one another, and of their genetic and environmental determinants, is complicated by the complexity of the causal connections and by the elusive nature of what constitutes the environment. In this project, we are assessing drug use and psychosocial stress in near-real time through Ecological Momentary Assessment (EMA), in which participants use handheld electronic diaries to record events as they occur and to report recent or ongoing events in response to randomly timed prompts throughout the day. We are also maintaining real-time records of where the reported events occurred by having participants carry Global Positioning System (GPS) devices to track their whereabouts with a spatial resolution of several meters. These data are being used collectively in a method we are calling Geographical Momentary Assessment (GMA), described further below. Analyses of EMA data in our population of polydrug users in treatment have shown that negative affect (stress), celebratory states, and drug cues are associated with subsequent cocaine use. Exposure to legal drugs, such as tobacco, is also strongly linked to cocaine use as well as cocaine craving. The likelihood of smoking tobacco at a given moment increased linearly with the current severity of cocaine craving (or dual craving for heroin and cocaine). The likelihood of tobacco smoking during episodes of use of cocaine (or cocaine and heroin), was greater still. This association remained significant after we controlled for demographic variables, location, and mood. These findings have implications for exposure to stress and illicit drugs and will be incorporated into our algorithms for risk-exposure assessment. We have also investigated the concomitants of urine-verified periods of cocaine use and abstinence. In a cohort design, a volunteer sample of 112 methadone-maintained cocaine- and heroin-abusing outpatients provided EMA data on handheld computers for 10,781 person-days. EMA responses to questions about current location, activities, companions, moods, and recent exposure to putative drug-use triggers were compared across periods of use and abstinence. Periods of cocaine use were associated with idle, solitary, affectively negative afternoons, but, unexpectedly, were also associated with a greater likelihood of early-morning or late-evening work. The whole-day concomitants of cocaine use were often distinct from the acute predecessors of use seen in prior analyses from the same sample. Several measures of negative mood increased during abstinence. Weeks of cocaine use and abstinence in outpatients are associated with distinct patterns of mood and behavior; the detailed hourly data reported here should help inform treatment interventions aimed at changing daily activities. Data from this study were also used to investigate the relationship between craving and drug use in real time and in the daily living environments of drug users. Craving is often assumed to cause ongoing drug use and relapse and is a major focus of addiction research. However, its relationship to drug use has not been adequately documented. Participants rated their craving and mood at random times (two to five times daily, prompted by electronic diaries) as they went about their everyday activities. They also initiated an electronic-diary entry each time they used cocaine. Drug use was monitored by thrice-weekly urine testing. During periods of urine-verified cocaine use, ratings of cocaine craving increased across the day and were higher than during periods of urine-verified abstinence. During the five hours prior to cocaine use, ratings of craving significantly increased. These patterns were not seen in ratings of heroin craving or mood (e.g., feeling happy or bored). Cocaine craving is tightly coupled to cocaine use in users normal environments. Our findings provide previously unavailable support for a relationship that has been seriously questioned in some theoretical accounts. Broadening the definition of environmental factors, we are using GMA, which incorporates continuous geolocation tracking, to evaluate neighborhood-level effects measured in terms of specially developed indices, such as the Neighborhood Psychosocial Hazards index (NPH), based on objective statistical data available from public sources and independent of self-report, plus the NIfETy, based on objective environmental ratings by trained observers. For comparison, we are also assessing drug exposure through retrospective interviews and from biological specimens (urine), and assessing stress through physiological measures (allostatic load). The result is expected to be a set of field-deployable, state-of-the-art tools indispensable to future studies of gene-environment interactions affecting drug use and stress. We have completed an initial pilot study to identify the appropriate GPS equipment and location sampling strategy and a developmental trial with 29 participants who carried the electronic diaries and GPS units for approximately 100 days. We are analyzing the real-time location data and combining it with EMA data and urine drug screen results for a completed GMA pilot study. We have also been developing measures of environmental risk based on publicly available databases and NIfETy data as part of risk exposure algorithm development. We are currently conducting a larger trial incorporating additional stress measures.