Health Outcomes by Neighborhood (HON): Effects of Neighborhood, Social Instability, and Health Factors on 12-Month Trajectories of Substance-Use Disorder Symptoms

BACKGROUND

Previous studies have shown that environment and health can influence drug use trajectories and the effects of substance use disorder (SUD) treatments. We hypothesized that trajectories of drug use-related problems, based on changes in DSM-5 symptoms, would vary by type(s) of drugs used, health factors, and neighborhood characteristics.

METHODS

We assessed mental and physical health, stress, social instability, neighborhood characteristics (disorderliness and home value), and DSM-5 symptom counts at two study visits, 12 months apart, in a community sample (baseline N = 735) in Baltimore, MD. Three prominent categories of drug-use trajectory were identified with K-means cluster analysis of symptom counts: Persistent (4 or more symptoms at both visits or at Visit 2), Improved (decrease from 4 or more symptoms at Visit 1 to 3 or fewer symptoms at Visit 2), and Low-Stable (3 or fewer symptoms at both visits). Baseline health and neighborhood measures were tested as predictors of trajectory in mediation and moderation models.

RESULTS

Among people with current opioid- and/or stimulant-use, odds of an Improved trajectory were (1) decreased with neighborhood disorder and social instability, or (2) increased with home value and social instability. Odds of a Low-Stable trajectory were decreased by social instability and stress but increased in those who were older or self-identified as white.

CONCLUSIONS

Trajectories of drug use-related problems are influenced by sociodemographic variables, neighborhood factors, and health. Assessing DSM-5 symptom counts as an outcome measure may be valuable in monitoring or predicting long-term trajectories and treatment effectiveness.

Clinical Trial Design Challenges and Opportunities for Emerging Treatments for Opioid Use Disorder: A Review

Importance

Novel treatments for opioid use disorder (OUD) are needed to address both the ongoing opioid epidemic and long-standing barriers to existing OUD treatments that target the endogenous μ-opioid receptor (MOR) system. The goal of this review is to highlight unique clinical trial design considerations for the study of emerging treatments for OUD that address targets beyond the MOR system. In November 2019, the Analgesic, Anesthetic, and Addiction Clinical Trial Translations, Innovations, Opportunities, and Networks (ACTTION) public-private partnership with the US Food and Drug Administration sponsored a meeting to discuss the current evidence regarding potential treatments for OUD, including cannabinoids, psychedelics, sedative-hypnotics, and immunotherapeutics, such as vaccines.

Observations

Consensus recommendations are presented regarding the most critical elements of trial design for the evaluation of novel OUD treatments, such as: (1) stage of treatment that will be targeted (eg, seeking treatment, early abstinence/detoxification, long-term recovery); (2) role of treatment (adjunctive with or independent of existing OUD treatments); (3) primary outcomes informed by patient preferences that assess opioid use (including changes in patterns of use), treatment retention, and/or global functioning and quality of life; and (4) adverse events, including the potential for opioid-related relapse or overdose, especially if the patient is not simultaneously taking maintenance MOR agonist or antagonist medications.

Conclusions and Relevance

Applying the recommendations provided here as well as considering input from people with lived experience in the design phase will accelerate the development, translation, and uptake of effective and safe therapeutics for individuals struggling with OUD.

Variability in intensively assessed mood: Systematic sources and factor structure in outpatients with opioid use disorder

In intensive longitudinal studies using ecological momentary assessment, mood is typically assessed by repeatedly obtaining ratings for a large set of adjectives. Summarizing and analyzing these mood data can be problematic because the reliability and factor structure of such measures have rarely been evaluated in this context, which-unlike cross-sectional studies-captures between- and within-person processes. Our study examined how mood ratings (obtained thrice daily for 8 weeks; n = 306, person moments = 39,321) systematically vary and covary in outpatients receiving medication for opioid use disorder (MOUD). We used generalizability theory to quantify several aspects of reliability, and multilevel confirmatory factor analysis (MCFA) to detect factor structures within and across people. Generalizability analyses showed that the largest proportion of systematic variance across mood items was at the person level, followed by the person-by-day interaction and the (comparatively small) person-by-moment interaction for items reflecting low arousal. The best-fitting MCFA model had a three-factor structure both at the between- and within-person levels: positive mood, negative mood, and low-arousal states (with low arousal considered as either a separate factor or a subfactor of negative mood). We conclude that (a) mood varied more between days than between moments and (b) low arousal may be worth scoring and reporting separately from positive and negative mood states, at least in a MOUD population. Our three-factor structure differs from prior analyses of mood; more work is needed to understand the extent to which it generalizes to other populations. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Intra-individual variability and stability of affect and craving among individuals receiving medication treatment for opioid use disorder

Affect and craving are dynamic processes that are clinically relevant in opioid use disorder (OUD) treatment, and can be quantified in terms of intra-individual variability and stability. The purpose of the present analysis was to explore associations between opioid use and variability and stability of affect and craving among individuals receiving medication treatment for OUD (MOUD). Adults (N = 224) with OUD in outpatient methadone or buprenorphine treatment completed ecological momentary assessment (EMA) prompts assessing positive affect, negative affect, opioid craving, and opioid use. Dynamic structural equation modeling (DSEM) was used to quantify person-level indices of magnitude and stability of change. Beta regression was used to examine associations between intra-individual variability and stability and proportion of opioid-use days, when controlling for overall intensity of affect and craving. Results suggested that greater magnitude of craving variability was associated with opioid use on a greater proportion of days, particularly among individuals with lower average craving. Low average positive affect was also associated with higher proportion of days of use. Individuals who experience substantial craving variability in the context of lower average craving may be particularly vulnerable to opioid use during treatment. Ongoing assessment of craving may be useful in identifying treatment needs. Examining correlates of intra-individual variability and stability in MOUD treatment remains a relevant direction for future work.

Trajectories of craving during medication-assisted treatment for opioid-use disorder: Subtyping for early identification of higher risk

AIMS

To examine evidence for subtypes of opioid craving trajectories during medication for opioid use disorder (MOUD), and to (a) test whether these subtypes differed on MOUD-related outcomes, and (b) determine whether nonresponders could be identified before treatment initiation.

DESIGN, SETTING, AND PARTICIPANTS

Outpatients (n = 211) being treated with buprenorphine or methadone for up to 16 weeks. Growth mixture modeling was used to identify unobserved craving-trajectory subtypes. Support Vector Machines (SVM) were trained to predict subtype membership from pretreatment data.

MEASUREMENTS

Self-reported opioid craving (Ecological Momentary Assessment - EMA - three random moments per day). Participant-initiated EMA reports of drug use or higher-than-usual stress. Addiction Severity Index (ASI) pretreatment.

FINDINGS

Four craving trajectories were identified: Low (73%); High and Increasing (HIC) (10.9%); Increasing and Decreasing (8.5%); and Rapidly Declining (7.6%). The HIC subgroup reported the highest use of heroin, any opiate, and cannabis during treatment. The Low Craving subgroup reported the lowest use of heroin or any opiate use, and the lowest levels of stress and drug-cue exposure during treatment. SVM models predicting HIC membership before treatment initiation had a sensitivity of 0.70, specificity of 0.78, and accuracy of 0.77. Including 3 weeks of EMA reports increased sensitivity to 0.78, specificity to 0.84, and accuracy to 0.85.

CONCLUSIONS

Subgroups of MOUD patients show distinct patterns of opioid craving during treatment. Subgroups differ on critical outcomes including drug-use lapse, stress, and exposure to drug cues. Data from enrollment and early in treatment may help focus clinical attention.

Nonfatal opioid overdoses before and after Covid-19: Regional variation in rates of change

Background

The Covid-19 pandemic and its accompanying public-health orders (PHOs) have led to (potentially countervailing) changes in various risk factors for overdose. To assess whether the net effects of these factors varied geographically, we examined regional variation in the impact of the PHOs on counts of nonfatal overdoses, which have received less attention than fatal overdoses, despite their public health significance.

Methods

Data were collected from the Overdose Detection Mapping Application Program (ODMAP), which recorded suspected overdoses between July 1, 2018 and October 25, 2020. We used segmented regression models to assess the impact of PHOs on nonfatal-overdose trends in Washington DC and the five geographical regions of Maryland, using a historical control time series to adjust for normative changes in overdoses that occurred around mid-March (when the PHOs were issued).

Results

The mean level change in nonfatal opioid overdoses immediately after mid-March was not reliably different in the Covid-19 year versus the preceding control time series for any region. However, the rate of increase in nonfatal overdose was steeper after mid-March in the Covid-19 year versus the preceding year for Maryland as a whole (B = 2.36; 95% CI, 0.65 to 4.06; p = .007) and for certain subregions. No differences were observed for Washington DC.

Conclusions

The pandemic and its accompanying PHOs were associated with steeper increases in nonfatal opioid overdoses in most but not all of the regions we assessed, with a net effect that was deleterious for the Maryland region as a whole.

Being at work improves stress, craving, and mood for people with opioid use disorder: Ecological momentary assessment during a randomized trial of experimental employment in a contingency-management-based therapeutic workplace

Employment problems are common among people with substance use disorders (SUDs), and improving vocational functioning is an important aspect of SUD treatment. More detailed understanding of the psychosocial benefits of employment may help refine vocational interventions for people with SUDs. Here, we used ecological momentary assessment to measure possible affective improvements associated with work. Participants (n = 161) with opioid use disorder were randomized to work (job-skills training) in a contingency-management-based Therapeutic Workplace either immediately or after a waitlist delay. Throughout, participants responded via smartphone to randomly scheduled questionnaires. In linear mixed models comparing responses made at work vs. all other locations, being at work was associated with: less stress, less craving for opioids and cocaine, less negative mood, more positive mood, and more flow-like states. Some of these differences were also observed on workdays vs. non-workdays outside of work hours. These results indicate that benefits associated with work may not be restricted to being actually in the workplace; however, randomization did not reveal clear changes coinciding with the onset of work access. Overall, in contrast to work-associated negative moods measured by experience-sampling in the general population, Therapeutic Workplace participants experienced several types of affective improvements associated with work.

Quality of life during a randomized trial of a therapeutic-workplace intervention for opioid use disorder: Web-based mobile assessments reveal effects of drug abstinence and access to paid work

Background

Employment and improved quality of life (QOL) are, separately, valued outcomes of substance use disorder (SUD) treatment. It is also important to understand QOL changes caused by employment itself; therefore, we assessed QOL during a randomized trial of a contingency-management-based Therapeutic Workplace for people with opioid use disorder.

Methods

For 12 weeks, participants (n = 61) responded to QOL questionnaires in a mobile web app accessed with study-issued smartphones. At enrollment, participants were randomized to work in the Therapeutic Workplace immediately (immediate work group, IWG) or after a 3-week waitlist delay (delayed work group, DWG). Once both groups could work, wage-resetting contingencies were introduced for their opiate- and cocaine-urinalysis. Data were analyzed by (1) access to work with and without contingencies and (2) overall urinalysis-verified opiate- and cocaine-abstinence.

Results

DWG and/or IWG reported improvements in several QOL areas (sleep, transportation, recreation); however, they also reported increased money-related difficulties and less time spent with friends/family. These changes did not coincide with DWG's work access, but some (more sleep, money-related difficulties) coincided with the urinalysis contingencies. Greater opiate- and/or cocaine-abstinence was also associated with several improvements: sleep, paying bills, time spent with friends/family, and exercising. Surprisingly, intermediate cocaine abstinence was associated with reductions in work-capacity satisfaction and recreation.

Conclusions

Participants reported complex QOL differences during their experimental employment and associated with drug abstinence. Future work should help participants address issues that may be relevant to employment generally (e.g., time with friends/family) or contingency management specifically (e.g., money-related issues for non-abstinent participants).

Reward Responsiveness in Patients with Opioid Use Disorder on Opioid Agonist Treatment: Role of Comorbid Chronic Pain

OBJECTIVE

Evidence suggests that blunted reward responsiveness may account for poor clinical outcomes in both opioid use disorder (OUD) and chronic pain. Understanding how individuals with OUD and comorbid chronic pain (OUD+CP) respond to rewards is, therefore, of clinical interest because it may reveal a potential point of behavioral intervention.

METHODS

Patients with OUD (n = 28) and OUD+CP (n = 19) on opioid agonist treatment were compared on: 1) the Probabilistic Reward Task (an objective behavioral measure of reward response bias) and 2) ecological momentary assessment of affective responses to pleasurable events.

RESULTS

Both the OUD and the OUD+CP groups evidenced an increase in reward response bias in the Probabilistic Reward Task. The rate of change in response bias across blocks was statistically significant in the OUD group (B = 0.06, standard error [SE] = 0.02, t = 3.92, P < 0.001, 95% confidence interval [CI]: 0.03 to 0.09) but not in the OUD+CP group (B = 0.03, SE = 0.02, t = 1.90, P = 0.07, 95% CI: -0.002 to 0.07). However, groups did not significantly differ in the rate of change in response bias across blocks (B = 0.03, SE = 0.02, t = 1.21, P = 0.23, 95% CI: -0.02 to 0.07). Groups did not significantly differ on state measures of reward responsiveness (P's ≥0.50).

CONCLUSIONS

Overall, findings across objective and subjective measures were mixed, necessitating follow-up with a larger sample. The results suggest that although there is a reward response bias in patients with OUD+CP treated with opioid agonist treatment relative to patients with OUD without CP, it is modest and does not appear to translate into patients' responses to rewarding events as they unfold in daily life.

I feel good? Anhedonia might not mean "without pleasure" for people treated for opioid use disorder

Anhedonia is usually defined as partial or total loss of the capacity for pleasure. People with anhedonia in the context of major depressive disorder may have an unexpected capacity for event-related mood brightening, observable when mood is assessed dynamically (with smartphone-based ecological momentary assessment [EMA]) rather than only statically via questionnaire. We used EMA to monitor mood and pleasant events for 4 weeks in 54 people being treated with opioid agonist medication for opioid-use disorder (OUD), which is also associated with anhedonia, said to manifest especially as loss of pleasure from nondrug reward. We compared OUD patients' EMA reports with those of 47 demographically similar controls. Background positive mood was lower in OUD patients than in controls, as we hypothesized (Cohen ds = .85 to 1.32, 95% CIs [.66, 1.55]), although, contrary to our hypothesis, background negative mood was also lower (ds = .82 to .85, 95% CIs [.73, .94]). As hypothesized, instances of nondrug pleasure were as frequent in OUD patients as in controls-and were not rated much less pleasurable (d = .18, 95% CI [-.03, .35]). Event-related mood brightening occurred in both abstinent and nonabstinent OUD patients (ds = .18 to .37, CIs [-.01, .57]) and controls (ds = .04 to .60, CIs [-.17, .79]), brightening before each event began earlier for controls than OUD patients, but faded similarly postevent across groups. Our findings add to the evidence that anhedonia does not rule out reactive mood brightening, which, for people with OUD being treated on opioid agonist medication, can be elicited by nondrug activities. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Longitudinal patterns of momentary stress during outpatient opioid agonist treatment: A growth-mixture-model approach to classifying patients

BACKGROUND

We previously showed, in people starting treatment for opioid use disorder (OUD), that stress is neither necessary nor sufficient for lapses to drug use to occur, despite an association between the two. Both theoretical clarity and case-by-case prediction accuracy may require initial differentiation among patients.

AIM

To examine: (a) evidence for distinct overall trajectories of momentary stress during OUD treatment, (b) relationships between stress trajectory and treatment response, and (c) relationships between stress trajectory and momentary changes in stress and craving prior to lapses.

METHODS

We used ecological momentary assessment (EMA) to collect ratings of stress and craving 3x/day for up to 16 weeks in 211 outpatients during agonist treatment for OUD. With growth mixture models, we identified trajectories of stress. We used mixed effect models to examine trajectory-group differences in the dynamics of stress and craving just before lapses to any drug use.

RESULTS

We identified four trajectories of stress: Increasing (13.7 %); Moderate and Stable (23.7 %); Declining and Increasing (18 %); and Low (44.6 %). Overall drug use and opioid craving were lowest in the Low Stress group. Overall drug use was highest in the Moderate and Stable group. Alcohol use and opioid craving were highest in the Increasing Stress group. Opioid craving increased before lapse for most groups, but stress increased before lapses for only the Moderate and Stable group.

CONCLUSION

There are natural groupings of participants with distinct patterns of stress severity during OUD treatment. Momentary stress/craving/lapse associations may be better characterized when these groupings are considered first.

Craving mediates the association between momentary pain and illicit opioid use during treatment for opioid-use disorder: an ecological momentary assessment study

AIM

To assess the role of momentary pain on opioid craving and illicit opioid use among individuals receiving opioid agonist treatment.

DESIGN

Observational study using ecological momentary assessment.

SETTING

The National Institute of Drug Abuse Intramural Research Program in the United States.

PARTICIPANTS

Fifty-six adults who qualified for opioid agonist treatment.

MEASUREMENTS

Participants completed randomly prompted assessments of pain severity, stress, negative mood, opioid craving and illicit opioid use for a mean of 66 days [standard deviation (SD) = 27]. Urine samples were collected two to three times/week throughout.

FINDINGS

Almost 70% of participants reported moderate average pain severity in the past 24 hours at intake and 35% of participants reported chronic pain. There were no significant differences in percent of opioid-positive urine samples (P = 0.73) and average level of opioid craving during the study period (P = 0.91) among opioid agonist treatment only patients versus opioid agonist treatment patients with chronic pain. However, momentary pain severity significantly predicted concurrent opioid craving [B = 0.02, 95% confidence interval (CI) = 0.01, 0.04], over and above stress and negative mood. Momentary opioid craving, in turn, significantly predicted illicit opioid use that was assessed in the next moment [odds ratio (OR) = 1.72, 95% CI = 1.12, 2.64), while controlling for autocorrelation and the effects of pain, negative mood and stress. Momentary opioid craving significantly mediated the prospective association between momentary pain and illicit opioid use (95% CI = 0.003, 0.032). Exploratory analysis revealed that momentary pain severity also significantly moderated the momentary association between stress and opioid craving (B = 0.02, 95% CI = 0.00, 0.04), such that when momentary pain severity increased, the association between the two intensified.

CONCLUSIONS

Among people receiving opioid agonist treatment, momentary pain appears to be indirectly associated with illicit opioid use via momentary opioid craving.

Beyond abstinence and relapse II: momentary relationships between stress, craving, and lapse within clusters of patients with similar patterns of drug use

RATIONALE

Given that many patients being treated for opioid-use disorder continue to use drugs, identifying clusters of patients who share similar patterns of use might provide insight into the disorder, the processes that affect it, and ways that treatment can be personalized.

OBJECTIVES AND METHODS

We applied hierarchical clustering to identify patterns of opioid and cocaine use in 309 participants being treated with methadone or buprenorphine (in a buprenorphine-naloxone formulation) for up to 16 weeks. A smartphone app was used to assess stress and craving at three random times per day over the course of the study.

RESULTS

Five basic patterns of use were identified: frequent opioid use, frequent cocaine use, frequent dual use (opioids and cocaine), sporadic use, and infrequent use. These patterns were differentially associated with medication (methadone vs. buprenorphine), race, age, drug-use history, drug-related problems prior to the study, stress-coping strategies, specific triggers of use events, and levels of cue exposure, craving, and negative mood. Craving tended to increase before use in all except those who used sporadically. Craving was sharply higher during the 90 min following moderate-to-severe stress in those with frequent use, but only moderately higher in those with infrequent or sporadic use.

CONCLUSIONS

People who share similar patterns of drug-use during treatment also tend to share similarities with respect to psychological processes that surround instances of use, such as stress-induced craving. Cluster analysis combined with smartphone-based experience sampling provides an effective strategy for studying how drug use is related to personal and environmental factors.

An Examination of the Feasibility of Detecting Cocaine Use Using Smartwatches

As digital technology increasingly informs clinical trials, novel ways to collect study data in the natural field setting have the potential to enhance the richness of research data. Cocaine use in clinical trials is usually collected via self-report and/or urine drug screen results, both of which have limitations. This article examines the feasibility of developing a wrist-worn device that can detect sufficient physiological data (i.e., heart rate and heart rate variability) to detect cocaine use. This study aimed to develop a wrist-worn device that can be used in the natural field setting among people who use cocaine to collect reliable data (determined by data yield, device wearability, and data quality) that is less obtrusive than chest-based devices used in prior research. The study also aimed to further develop a cocaine use detection algorithm used in previous research with an electrocardiogram on a chestband by adapting it to a photoplethysmography sensor on the wrist-worn device which is more prone to motion artifacts. Results indicate that wrist-based heart rate data collection is feasible and can provide higher data yield than chest-based sensors, as wrist-based devices were also more comfortable and affected participants' daily lives less often than chest-based sensors. When properly worn, wrist-based sensors produced similar quality of heart rate and heart rate variability features to chest-based sensors and matched their performance in automated detection of cocaine use events. Clinical Trial Registration: www.ClinicalTrials.gov, identifier: NCT02915341.

Exploring the Relationship Between Substance Use and Allostatic Load in a Treatment/Research Cohort and in a US Probability Sample (NHANES 2009-2016)

Allostatic load, an operationalization for cumulative strain on physiology from adaptation (allostasis) to stress over a lifetime, can manifest as damage to cardiovascular, neuroendocrine, and metabolic systems. The concept of allostatic load may be particularly useful in research on substance-use disorders (SUDs) because SUD researchers have sought to better understand the relationship between chronic stressors and drug use. Theoretical models hold that SUDs can be conceptualized as a spiral toward a state of persistent allostasis (i.e., allostasis so persistent as to represent homeostasis at a new, unhealthy set point). Regardless of the extent to which those models are accurate, increased allostatic load could be a mechanism by which frequent drug administration increases risk for adverse outcomes. We conducted two secondary analyses to evaluate allostatic load in the context of drug use, including alcohol use, in a locally recruited sample with a high proportion of illicit substance use (N = 752) and in a nationally representative sample from the NHANES 2009-2016. We hypothesized that after controlling for age and other potential confounds, people with longer histories of drug use would have higher allostatic-load scores. Multiple regression was used to predict allostatic load from participants' drug-use histories while controlling for known confounds. In the locally recruited sample, we found that longer lifetime use of cocaine or opioids was related to increased allostatic load. In NHANES 2009-2016, we found few or no such associations. Lengthy histories of problematic non-medical substance use may facilitate more rapid increases in allostatic load than aging alone, and, together with findings from previous investigations, this finding suggests increased risk for chronic disease.

Subtherapeutic Acetazolamide Doses as a Noninvasive Method for Assessing Medication Adherence

Adherence monitoring is a vital component of clinical efficacy trials, as the regularity of medication consumption affects both efficacy and adverse effect profiles. Pill-counts do not confirm consumption, and invasive plasma assessments can only assist post hoc assessments. We previously reported on the pharmacokinetics of a potential adherence marker to noninvasively monitor dosage consumption during a trial without breaking a blind. We reported that consumption cessation of subtherapeutic 15 mg acetazolamide (ACZ) doses showed a predictable urinary excretion decay that was quantifiable for an extended period. The current study describes the clinical implementation of 15 mg ACZ doses as an adherence marker excipient in distinct cohorts taking ACZ for different "adherence" durations. We confirm that ACZ output did not change (accumulate) during 18-20 days of adherence, and developed and assessed urinary cutoffs as nonadherence indicators. We demonstrate that whereas an absolute concentration cutoff (989 ng/mL) lacked sensitivity, a creatinine normalized equivalent (1,376 ng/mg ACZ) was highly accurate at detecting nonadherence. We also demonstrate that during nonadherent phases of three trials, creatinine-normalized urinary ACZ elimination was reproducible within and across trials with low variability. Excretion was first order, with a decay half-life averaging ~ 2.0 days. Further, excretion remained quantifiable for 14 days, providing a long period during which the date of last consumption might be determined. We conclude that inclusion of 15 mg ACZ as a dosage form adherence marker excipient, provides a reliable and sensitive mechanism to confirm medication consumption and detect nonadherence during clinical efficacy trials.

Prediction of stress and drug craving ninety minutes in the future with passively collected GPS data

Just-in-time adaptive interventions (JITAIs), typically smartphone apps, learn to deliver therapeutic content when users need it. The challenge is to "push" content at algorithmically chosen moments without making users trigger it with effortful input. We trained a randomForest algorithm to predict heroin craving, cocaine craving, or stress (reported via smartphone app 3x/day) 90 min into the future, using 16 weeks of field data from 189 outpatients being treated for opioid-use disorder. We used only one form of continuous input (along with person-level demographic data), collected passively: an indicator of environmental exposures along the past 5 h of movement, as assessed by GPS. Our models achieved excellent overall accuracy-as high as 0.93 by the end of 16 weeks of tailoring-but this was driven mostly by correct predictions of absence. For predictions of presence, "believability" (positive predictive value, PPV) usually peaked in the high 0.70s toward the end of the 16 weeks. When the prediction target was more rare, PPV was lower. Our findings complement those of other investigators who use machine learning with more broadly based "digital phenotyping" inputs to predict or detect mental and behavioral events. When target events are comparatively subtle, like stress or drug craving, accurate detection or prediction probably needs effortful input from users, not passive monitoring alone. We discuss ways in which accuracy is difficult to achieve or even assess, and warn that high overall accuracy (including high specificity) can mask the abundance of false alarms that low PPV reveals.

Multimodal assessment of sleep in men and women during treatment for opioid use disorder

BACKGROUND

Sleep disturbance is common in patients with opioid use disorder (OUD) receiving medication for addiction treatment. Differences between patients on the two primary agonist medications-methadone and buprenorphine-are not well understood.

METHODS

In patients receiving either methadone or buprenorphine treatment for OUD, we examined sleep continuity and architecture using ambulatory monitoring to gather both an objective measure (daily sleep EEG; M = 5.76 days, SD = 1.46) and a subjective measure (daily sleep diary; M = 54.10 days, SD = 25.10) of sleep.

RESULTS

Patients treated with buprenorphine versus methadone did not differ on any measure of sleep continuity or architecture. Women had longer EEG-derived total sleep time than men (d = -0.68, 95 % CI -1.32 to -0.09), along with lower %N2 (d = 0.94, 95 % CI 0.34-1.64) and greater %N3 (d = -0.94, 95 % CI -1.61 to -0.32). Self-reported sleep differed from EEG-derived estimates: wake after sleep onset was greater by EEG than by diary (d = 2.58, 95 % CI 1.74-3.63), and total sleep time and sleep efficiency were lower by EEG than by diary (d for sleep time = 2.93, 95 % CI 2.06-4.14; d for efficiency = 1.69, 95 % CI 0.98-2.49).

CONCLUSIONS

Patients treated with buprenorphine or methadone did not substantively differ in ambulatory measures of sleep. With both medications, there was a discrepancy between objective and subjective sleep measures. Further confirmatory evidence would inform the development of sleep-related recommendations for OUD patients undergoing agonist treatment.

Using mobile location data in biomedical research while preserving privacy

Location data are becoming easier to obtain and are now bundled with other metadata in a variety of biomedical research applications. At the same time, the level of sophistication required to protect patient privacy is also increasing. In this article, we provide guidance for institutional review boards (IRBs) to make informed decisions about privacy protections in protocols involving location data. We provide an overview of some of the major categories of technical algorithms and medical-legal tools at the disposal of investigators, as well as the shortcomings of each. Although there is no "one size fits all" approach to privacy protection, this article attempts to describe a set of practical considerations that can be used by investigators, journal editors, and IRBs.

Craving and opioid use disorder: A scoping review

INTRODUCTION

The subjective experience of drug craving is a prominent and common clinical phenomenon for many individuals diagnosed with opioid use disorder (OUD), and could be a valuable clinical endpoint in medication development studies. The purpose of this scoping review is to provide an overview and critical analysis of opioid craving assessments located in the published literature examining OUD.

METHOD

Studies were identified through a search of PubMed, Embase, and PsychInfo databases and included for review if opioid craving was the focus and participants were diagnosed with or in treatment for OUD.

RESULTS

Fifteen opioid craving assessment instruments were identified across the 87 studies included for review. The most common were the Visual Analog Scale (VAS, 41 studies), Desires for Drug Questionnaire (DDQ, 12 studies), Heroin Craving Questionnaire (HCQ, 10 studies), and Obsessive-Compulsive Drug Use Scale (OCDUS, 10 studies). Craving assessments varied considerably in their format, content, time frame, and underlying subscales, and only 6 of 15 had been psychometrically evaluated.

DISCUSSION

This review identified a variety of opioid craving assessments, but few had been evaluated for their psychometric properties making it difficult to ascertain whether craving is being assessed optimally in studies of OUD. Thus, the development of a reliable and valid opioid craving assessment would be worthwhile and could be guided by recently published Food and Drug Administration Clinical Outcome Assessment (COA) guidelines. Importantly, a COA focused on opioid craving could be a valuable addition to research studies designed to evaluate novel treatments for OUD.

The chippers, the quitters, and the highly symptomatic: A 12-month longitudinal study of DSM-5 opioid- and cocaine-use problems in a community sample

BACKGROUND

Individual trajectories of drug use and drug-related problems are highly heterogeneous. There is no standard taxonomy of these trajectories, but one could be developed by defining natural categories based on changes in symptoms of substance-use disorders over time.

METHODS

Our study was conducted in a community sample in Baltimore, Maryland. At baseline, all participants were using opioids and/or cocaine, but none were in treatment. Drug use and symptomatology were assessed again at 12 months (N = 115).

RESULTS

We defined Quitters as participants who had not used for at least 30 days at follow-up (17%). For the remaining participants, we performed longitudinal cluster analysis on DSM symptom-counts, identifying three trajectory clusters: newly or persistently Symptomatic (40%) participants, Chippers (21.5%) with few symptoms, and Converted Chippers (21.5%) with improved symptom counts. Logistic regression showed that profiles of Quitters did not resemble Chippers, but instead resembled Symptomatic participants, having high probability of disorderly home neighborhood, nonwhite race, and negative mood. Quitters tended to have two protective factors: initiating opioid-agonist treatment during the study (r_effect = 0.25, CL95 0.02-0.48) and lack of polydrug use (r_effect = 0.25, CL95 0.004-0.49). Converted Chippers tended to be white, with orderly home neighborhoods and less negative mood (r_effects 0.24 to 0.31, CL95 0.01-0.54).

CONCLUSIONS

Changes in DSM symptomology provided a meaningful measure of individual trajectories. Quitters shared psychosocial characteristics with Symptomatic participants, but not with participants who continued to use with few symptoms. This suggests that Quitters abstained out of necessity, not because their problems were less severe.

Striatal Dopamine Release in Response to Morphine: A [11C]Raclopride Positron Emission Tomography Study in Healthy Men

BACKGROUND

Preclinical and human positron emission tomography studies have produced inconsistent results regarding the effects of opioids on mesolimbic dopamine (DA). Here, we quantify striatal DA release (measured by [11C]raclopride displacement) in response to an intravenous infusion of morphine, and its relationship with morphine-induced subjective effects, in healthy, nondependent opioid-experienced participants.

METHODS

Fifteen healthy male participants were initially included. Sessions were on separate days. On session 1, participants received intravenous morphine (10 mg/70 kg) in the clinic to ensure tolerability. Participants without adverse reactions (n = 10) then received intravenous morphine and placebo (saline) sessions, in counterbalanced order, while undergoing [11C]raclopride positron emission tomography scans. Subjective and physiological responses were assessed. Region-of-interest and voxelwise image analyses were used to assess changes in [11C]raclopride nondisplaceable binding potential.

RESULTS

Morphine produced marked subjective and physiological effects and induced a significant decrease in [11C]raclopride nondisplaceable binding potential, particularly in the nucleus accumbens and globus pallidus, where the change in [11C]raclopride nondisplaceable binding potential was approximately 9%. However, the subjective effects of morphine did not show a simple pattern of correlation with DA release.

CONCLUSIONS

This is, to our knowledge, the first study providing in vivo human evidence that DA transmission in the ventral striatum is affected by morphine. Further studies are required to fully delineate the DA contribution to the reinforcing effects of opioids.

Stress, craving and mood as predictors of early dropout from opioid agonist therapy

BACKGROUND

Treatment with opioid agonists is effective for opioid use disorder, but early discontinuation of treatment is a major obstacle to success. Intensive longitudinal methods - which take many repeated measurements over time, usually in the field- have provided unique insight into the effects of stress, mood and craving on drug use while people are being treated; these methods might also be useful for studying the processes that lead people to drop out of treatment.

METHODS

Ecological momentary assessment (EMA) was conducted for up to 17 weeks by obtaining multiple electronic diary entries per day from 238 participants being treated with methadone or buprenorphine-naloxone. Survival analysis was used to study two outcomes: dropping out of treatment and noncompliance with EMA self-report requirements. Self-reports of stress, craving, and mood were used as time-varying predictors. Demographic and psychosocial variables measured with the Addiction Severity Index at the start of treatment were used as time-invariant predictors.

RESULTS

Dropping out of treatment was more likely in participants with more reported hassles (a measure of stress), higher levels of cocaine craving, lower levels of positive mood, a recent history of emotional abuse, a recent history of being bothered frequently by psychological problems, and with buprenorphine rather than methadone as their medication. In contrast, study noncompliance was not significantly associated with any of the variables analyzed.

CONCLUSIONS

Assessment of stress, craving and mood during treatment might identify people who are at greater risk of dropping out, and therapeutic interventions targeting these processes might increase retention.

Sleep reductions associated with illicit opioid use and clinic-hour changes during opioid agonist treatment for opioid dependence: Measurement by electronic diary and actigraphy

Sleep problems are commonly reported during opioid agonist treatment (OAT) for opioid use disorders. Inpatient studies have found both sleep disturbances and improved sleep during OAT. Illicit opioids can also disrupt sleep, but it is unclear how they affect sleep in outpatients receiving OAT. Therefore, we used electronic diary entries and actigraphy to measure sleep duration and timing in opioid-dependent participants (n = 37) treated with methadone (n = 15) or buprenorphine (n = 22). For 16 weeks, participants were assigned to attend our clinic under different operating hours in a crossover design: Early hours (07:00-09:00) vs. Late hours (12:00-13:00) for 4 weeks each in randomized order, followed for all participants by our Standard clinic hours (07:00-11:30) for 8 weeks. Throughout, participants made daily electronic diary self-reports of their sleep upon waking; they also wore a wrist actigraph for 6 nights in each of the three clinic-hour conditions. Drug use was assessed by thrice-weekly urinalysis. In linear mixed models controlling for other sleep-relevant factors, sleep duration and timing differed by drug use and by clinic hours. Compared to when non-using, participants slept less, went to bed later, and woke later when using illicit opioids and/or both illicit opioids and cocaine. Participants slept less and woke earlier when assigned to the Early hours. These findings highlight the role OAT clinic schedules can play in structuring the sleep/wake cycles of OAT patients and clarify some of the circumstances under which OAT patients experience sleep disruption in daily life.

Towards detecting cocaine use using smartwatches in the NIDA clinical trials network: Design, rationale, and methodology

Cocaine use in clinical trials is often measured via self-report, which can be inaccurate, or urine drug screens, which can be intrusive and burdensome. Devices that can automatically detect cocaine use and can be worn conveniently in daily life may provide several benefits. AutoSense is a wearable, physiological-monitoring suite that can detect cocaine use, but it may be limited as a method for monitoring cocaine use because it requires wearing a chestband with electrodes. This paper describes the design, rationale, and methodology of a project that seeks to build upon and extend previous work in the development of methods to detect cocaine use via wearable, unobtrusive mobile sensor technologies. To this end, a wrist-worn sensor suite (i.e., MotionSense HRV) will be developed and evaluated. Participants who use cocaine (N = 25) will be asked to wear MotionSense HRV and AutoSense for two weeks during waking hours. Drug use will be assessed via thrice-weekly urine drug screens and self-reports, and will be used to isolate periods of cocaine use that will be differentiated from other drug use. The present study will provide information on the feasibility and acceptability of using a wrist-worn device to detect cocaine use.

Defining and Predicting Opioid and Cocaine Treatment Response

Background: Treatment with methadone is effective in reducing heroin use, HIV risk, and death; however, not all patients respond to treatment. Better outcomes may emerge with personalized treatment based on factors that influence treatment courses. Objectives: To investigate psychosocial variables contributing to treatment response, using a comprehensive definition of treatment response. Methods: Seventy participants seeking treatment for heroin and cocaine addiction completed up to 40 weeks of daily methadone. At week 22, we administered a semi-structured interview for DSM-IV symptoms. We defined opioid treatment responders as people still enrolled at 22 weeks, not meeting past 30-day criteria for DSM-IV opioid abuse or dependence or DSM-5 opioid use disorder, and providing ≥75% opioid-negative urine samples in the 30 days prior to week 22. The same criteria were applied to assess cocaine treatment response. Results: Sample was 71% male, 41% White, and averaged 39.4 ± 7.9 years old. Opioid treatment response was more likely in participants who had been employed over the past 3 years (OR: 8.1, 95% CI: 1.2-55) and less likely in those who spent more time on hobbies (OR: 0.45, 95% CI: 0.23-0.88). Cocaine treatment response was more likely in participants who had a good relationship with their father (OR: 5.3, 95% CI: 1.2-24) and less likely if positive for hepatitis C (OR: 0.15, 95% CI: 0.03-0.75). Conclusions: Pretreatment characteristics differentially predict treatment response for heroin and cocaine use. Similar research in diverse patient groups may aid in the development of personalized treatment combining biologic treatment with targeted psychosocial interventions.

End-of-day reports of daily hassles and stress in men and women with opioid-use disorder: Relationship to momentary reports of opioid and cocaine use and stress

BACKGROUND AND AIMS

Stress can be validly assessed "live" or by a summary evaluation of the very recent past. Using smartphone-based ecological momentary assessment (EMA) combined with end-of-day (EOD) entries, we assessed the association between daily hassles, stressful events and use of opioids and cocaine, in opioid- and cocaine-using men and women.

METHODS

For up to 16 weeks, 161 outpatients in opioid-agonist treatment who reported cigarette smoking carried smartphones on which they reported stressful events (SEs) and drug use (DU) and completed an EOD questionnaire to report hassles encountered throughout the day, current perceived stress, cigarettes/day, and current mood. We compared EOD responses on days with and without SE and DU reports and on days when thrice-weekly urine drug screens indicated opioid or cocaine use or abstinence.

RESULTS

Participants (N = 161) made 11,544 EOD entries; EMA SEs were reported on 861 (7.5%) days, and DUs on 1685 (14.6%) days. The most frequently reported hassles in EOD entries were "not enough money" (31.4% of daily reports) and maintaining abstinence (18.7%). Total EOD hassles showed small but statistically significant associations [odds ratios (95% CIs)] with EMA SEs [1.09 (1.06-1.13)], DUs [1.08 (1.06-1.10)], and urine-positive opioid [1.06 (1.04-1.09)] and cocaine [1.03 (1.00-1.06)] results. Men and women had similar rates (mean/day (SD)) of hassles: men 2.25 (3.55); women 2.55 (3.76) (F_1,159 = 0.53, p = 0.47).

CONCLUSIONS

Daily hassles, reported at the end of the day, are associated with both same-day stressful events and drug use. Monitoring hassles and devising specific coping strategies might be useful therapeutic targets.

Before and after: craving, mood, and background stress in the hours surrounding drug use and stressful events in patients with opioid-use disorder

RATIONALE

Ecological momentary assessment (EMA) of specific events usually focuses more on antecedents and concomitants than on aftermaths.

OBJECTIVES

To examine mental state both before and after discrete episodes of stress and drug use.

METHODS

For up to 16 weeks, outpatients on opioid-agonist treatment carried smartphones on which they initiated entries for stressful events (SEs) or lapses to drug use (DUs), and thrice daily when randomly prompted (RPs). Participants rated their stress, opioid craving, cocaine craving, and moods. RP entries within 5 h of an event were analyzed and compared to other RPs.

RESULTS

Stress, negative mood, and craving were generally higher before and after DUs and SEs compared to background levels in participants with at least one DU (n = 149) or SE (n = 158). Before DUs, there were increases in negative mood, opioid craving, and cocaine craving, but not background stress. Before SEs, there were increases in background stress, opioid craving, and cocaine craving, but not negative mood. These changes were more variable after events than before. Neither DUs nor SEs were significantly related to positive mood.

CONCLUSIONS

Stress increased before stressful-event entries, but was less evident before drug use. Craving increased in the hours before drug use and stressful events-and remained elevated in the hours after either event. These results suggest a stronger link between drug use and craving than between drug use and stress. Lapses to drug use did not improve mood or reduce stress, at least not at our 1-h-bin time resolution, suggesting that if such benefits exist, they are brief.

Sex differences in daily life stress and craving in opioid-dependent patients

BACKGROUND

Responses to stress and drug craving differ between men and women. Differences in the momentary experience of stress in relation to craving are less well-understood.

OBJECTIVES

Using ecological momentary assessment (EMA), we examined sex differences in real-time in two areas: (1) causes and contexts associated with stress, and (2) the extent to which stress and drug cues are associated with craving.

METHODS

Outpatients on opioid-agonist treatment (135 males, 47 females) reported stress, craving, and behavior on smartphones for 16 weeks. They initiated an entry each time they felt more stressed than usual (stress event) and made randomly prompted entries 3 times/day. In stress-event entries, they identified the causes and context (location, activity, companions), and rated stress and craving severity.

RESULTS

The causes reported for stress events did not differ significantly by sex. Women reported arguing and being in a store more often during stress events, and men reported working more often during stress events, compared to base rates (assessed via random prompts). Women showed a greater increase in opioid craving as a function of stress (p < 0.0001) and had higher stress ratings in the presence of both stress and drug cues relative to men (p < 0.01). Similar effects were found for cocaine craving in men (p < 0.0001).

CONCLUSION

EMA methods provide evidence based on real-time activities and moods that opioid-dependent men and women experience similar contexts and causes for stress but differ in stress- and cue-induced craving. These findings support sex-based tailoring of treatment, but because not all participants conformed to the overall pattern of sex differences, any such tailoring should also consider person-level differences.

Using ecological momentary assessment to examine the relationship between craving and affect with opioid use in a clinical trial of clonidine as an adjunct medication to buprenorphine treatment

BACKGROUND

In a recent clinical trial (NCT00295308), we demonstrated that clonidine decreased the association between opioid craving and moderate levels of stress and affect in patients receiving buprenorphine-based opioid agonist therapy.

OBJECTIVES

To examine the relationship between illicit opioid use and craving and affect during the evaluation of clonidine as an adjunct medication in buprenorphine treatment for opioid use disorder. Secondarily, to examine whether those relationships are driven by within- or between-participant factors.

METHODS

This was a secondary data analysis from our original trial. Participants (N = 108, female: n = 23, male n = 85) receiving buprenorphine were randomized to receive adjunct clonidine or placebo. Participants used portable electronic devices to rate stress, mood, and craving via ecological momentary assessment (EMA) four times randomly each day. To associate the EMA data with illicit opioid use, each EMA report was linked to participants' next urine drug screen (thrice weekly). We used generalized linear mixed models to examine the interaction between treatment group and illicit opioid use, as well as to decompose the analysis into within- and between-participant effects.

RESULTS

Craving for opioids and cocaine was increased when participants were using illicit opioids; this effect was greater in the clonidine group. For affect, mood was poorer during periods preceding opioid-positive urines than opioid-negative urines for clonidine-treated participants, whereas there was no difference for placebo participants.

CONCLUSION

This secondary analysis provides evidence that for participants maintained on opioid agonist therapy, clonidine minimized the behavioral impact of moderate levels of negative affect and craving.

Exacerbated Craving in the Presence of Stress and Drug Cues in Drug-Dependent Patients

In addiction, risk factors for craving and use include stress and drug-related cues. Stress and cues have additive or more-than-additive effects on drug seeking in laboratory animals, but, surprisingly, seem to compete with one another (ie, exert less-than-additive effects) in human laboratory studies of craving. We sought heretofore elusive evidence that human drug users could show additive (or more-than-additive) effects of stress and cues on craving, using ecological momentary assessment (EMA). Outpatients (N=182) maintained on daily buprenorphine or methadone provided self-reports of stress, craving, mood, and behavior on electronic diaries for up to 16 weeks. In three randomly prompted entries (RPs) per day, participants reported the severity of stress and craving and whether they had seen or been offered opioids, cocaine, cannabis, methamphetamine, alcohol, or tobacco. In random-effects models controlling for between-person differences, we tested effects of momentary drug-cue exposure and stress (and their interaction) on momentary ratings of cocaine and heroin craving. For cocaine craving, the Stress × Cue interaction term had a positive mean effect across participants (M=0.019; CL95 0.001-0.036), denoting a more-than-additive effect. For heroin, the mean was not significantly greater than 0, but the confidence interval was predominantly positive (M=0.019; CL95 -0.007-0.044), suggesting at least an additive effect. Heterogeneity was substantial; qualitatively, the Stress × Cue effect appeared additive for most participants, more than additive for a sizeable minority, and competitive in very few. In the field, unlike in human laboratory studies to date, craving for cocaine and heroin is greater with the combination of drug cues and stress than with either alone. For a substantial minority of users, the combined effect may be more than additive.

Context and craving during stressful events in the daily lives of drug-dependent patients

RATIONALE

Knowing how stress manifests in the lives of people with substance-use disorders could help inform mobile "just in time" treatment.

OBJECTIVES

The purpose of this paper is to examine discrete episodes of stress, as distinct from the fluctuations in background stress assessed in most EMA studies.

METHODS

For up to 16 weeks, outpatients on opioid-agonist treatment carried smartphones on which they initiated an entry whenever they experienced a stressful event (SE) and when randomly prompted (RP) three times daily. Participants reported the severity of stress and craving and the context of the report (location, activities, companions). Decomposition of covariance was used to separate within-person from between-person effects; r _effect sizes below are within-person.

RESULTS

Participants (158 of 182; 87%) made 1787 stress-event entries. Craving for opioids increased with stress severity (r _effect = 0.50). Stress events tended to occur in social company (with acquaintances, 0.63, friends, 0.17, or on the phone, 0.41) rather than with family (spouse, -0.14; child, -0.18), and in places with more overall activity (bars, 0.32; outside, 0.28; walking, 0.28) and more likelihood of unexpected experiences (with strangers, 0.17). Being on the internet was slightly protective (-0.22). Our prior finding that being at the workplace protects against background stress in our participants was partly supported in these stressful-event data.

CONCLUSIONS

The contexts of specific stressful events differ from those we have seen in prior studies of ongoing background stress. However, both are associated with drug craving.

A role for muscarinic receptors in neutrophil extracellular trap formation and levamisole-induced autoimmunity

Levamisole, an anthelmintic drug with cholinergic properties, has been implicated in cases of drug-induced vasculitis when added to cocaine for profit purposes. Neutrophil extracellular trap (NET) formation is a cell death mechanism characterized by extrusion of chromatin decorated with granule proteins. Aberrant NET formation and degradation have been implicated in idiopathic autoimmune diseases that share features with levamisole-induced autoimmunity as well as in drug-induced autoimmunity. This study's objective was to determine how levamisole modulates neutrophil biology and its putative effects on the vasculature. Murine and human neutrophils exposed to levamisole demonstrated enhanced NET formation through engagement of muscarinic subtype 3 receptor. Levamisole-induced NETosis required activation of Akt and the RAF/MEK/ERK pathway, ROS induction through the nicotinamide adenine dinucleotide phosphate oxidase, and peptidylarginine deiminase activation. Sera from two cohorts of patients actively using levamisole-adulterated cocaine displayed autoantibodies against NET components. Cutaneous biopsy material obtained from individuals exposed to levamisole suggests that neutrophils produce NETs in areas of vasculitic inflammation and thrombosis. NETs generated by levamisole were toxic to endothelial cells and impaired endothelium-dependent vasorelaxation. Stimulation of muscarinic receptors on neutrophils by cholinergic agonists may contribute to the pathophysiology observed in drug-induced autoimmunity through the induction of inflammatory responses and neutrophil-induced vascular damage.

Cognitive-behavioural therapy for heroin and cocaine use: Ecological momentary assessment of homework simplification and compliance

OBJECTIVES

The purpose of this study was to evaluate the effects of homework-task difficulty and electronic-diary reminders on written homework completion during cognitive-behavioural therapy (CBT) for addiction. Completion of homework is an important element in CBT that may affect outcome.

DESIGN

All participants received all combinations of our two interventions in a factorial 2 × 2 counterbalanced Latin-square design.

METHODS

Methadone-maintained cocaine and heroin users were given homework between each of 12 weekly CBT sessions and carried electronic diaries that collected ecological momentary assessment (EMA) data on craving and exposure to drug-use triggers in four 3-week blocks assessing two levels of homework difficulty and prompted and unprompted homework.

RESULTS

Neither simplified (picture-based) homework nor electronic reminders increased homework completion. In EMA reports, standard but not simplified homework seemed to buffer the craving that followed environmental exposure to drug cues. EMA recordings before and after the CBT intervention confirmed a decrease over time in craving for cocaine and heroin.

CONCLUSIONS

These findings demonstrate the utility of EMA to assess treatment effects. However, the hypothesis that simplified homework would increase compliance was not supported.

PRACTITIONER POINTS

Our simplifications of homework assignments for cognitive-behavioural therapy were mostly ineffective, or even counterproductive, perhaps because they did not engage sufficient depth of processing or because they were perceived as too simplistic. Our reminder beeps for homework were mostly ineffective, or even counterproductive, suggesting that mobile electronic interventions for substance-use disorders may need to be more interactive.

Using iPSC-derived human DA neurons from opioid-dependent subjects to study dopamine dynamics

INTRODUCTION

The dopaminergic (DA) system plays important roles in addiction. However, human DA neurons from drug-dependent subjects were not available for study until recent development in inducible pluripotent stem cells (iPSCs) technology.

METHODS

In this study, we produced DA neurons differentiated using iPSCs derived from opioid-dependent and control subjects carrying different 3' VNTR (variable number tandem repeat) polymorphism in the human dopamine transporter (DAT or SLC6A3). In addition, the effects of valproic acid (VPA) exposures on iPSC-derived human DA neurons are also examined.

RESULTS

We present the first evidence suggesting that the 3' VNTR polymorphism in the hDAT gene affects DAT expression level in iPSC-derived human DA neurons. In human DA neurons, which provide an appropriate cellular milieu, VPA treatment alters the expression of several genes important for dopaminergic neuron function including DAT, Nurr1, and TH; this might partly explain its action in regulating addictive behaviors. VPA treatment also significantly increased DA D2 receptor (Drd2) expression, especially in the opioid-dependent iPSC cell lines.

CONCLUSIONS

Our data suggest that human iPSC-derived DA neurons may be useful in in vitro experimental model to examine the effects of genetic variation in gene regulation, to examine the underlying mechanisms in neurological disorders including drug addiction, and to serve as a platform for therapeutic development.

Finding Significant Stress Episodes in a Discontinuous Time Series of Rapidly Varying Mobile Sensor Data

Management of daily stress can be greatly improved by delivering sensor-triggered just-in-time interventions (JITIs) on mobile devices. The success of such JITIs critically depends on being able to mine the time series of noisy sensor data to find the most opportune moments. In this paper, we propose a time series pattern mining method to detect significant stress episodes in a time series of discontinuous and rapidly varying stress data. We apply our model to 4 weeks of physiological, GPS, and activity data collected from 38 users in their natural environment to discover patterns of stress in real-life. We find that the duration of a prior stress episode predicts the duration of the next stress episode and stress in mornings and evenings is lower than during the day. We then analyze the relationship between stress and objectively rated disorder in the surrounding neighborhood and develop a model to predict stressful episodes.

Tailored, interactive text messages for enhancing weight loss among African American adults: the TRIMM randomized controlled trial

BACKGROUND

Helping patients control obesity remains a clinical challenge for internists, and African Americans experience obesity rates higher than other racial/ethnic groups.

PURPOSE

To investigate whether a behavioral theory-based mobile health intervention would enhance weight loss when added to standard care among overweight/obese African American adults.

METHODS

A randomized controlled trial of 124 adults recruited from Baltimore-area African American churches. Participant follow-up ended March 2013. Participants were randomized to standard care (included one-on-one counseling sessions with a dietitian and a physician) or standard care plus daily tailored text messages for 6 months. Text messages were delivered in phases: preparation, reinforcement of participant-selected diet and exercise goals, reflection, goal integration, weight loss methods, and maintenance. There were follow-up visits at 3, 6, and 12 months. Primary outcome was weight change from baseline to end-intervention at 6 months. Secondary outcomes included weight change at 3 months, engagement, and satisfaction with the intervention.

RESULTS

Sixty-three participants were randomized to the mobile health intervention and 61 to standard-care control. Weights were collected in-window for 45 (36.3%) at 3 months and 51 (41.1%) at 6 months. Mean weight loss at 3 months was 2.5 kg greater in the intervention group compared with standard care (95% confidence interval [CI], -4.3 to -0.6; P < .001), and 3.4 kg greater (95% CI, -5.2 to -1.7; P = .001) at 6 months. Degree of engagement with messages was correlated with weight loss.

CONCLUSIONS

While attrition was high, this study supports a tailored, interactive text-message intervention to enhance weight loss among obese African-American adults.

Clonidine Maintenance Prolongs Opioid Abstinence and Decouples Stress From Craving in Daily Life: A Randomized Controlled Trial With Ecological Momentary Assessment

OBJECTIVE

The authors tested whether clonidine blocks stress-induced seeking of heroin and cocaine. The study was also intended to confirm translational findings from a rat model of drug relapse by using ecological momentary assessment of patients' stress to test hypotheses about clonidine's behavioral mechanism of action.

METHOD

The authors conducted a randomized double-blind placebo-controlled clinical trial with 208 opioid-dependent patients at an outpatient buprenorphine clinic. The 118 participants (57%) who maintained abstinence during weeks 5-6 were continued on buprenorphine and randomly assigned to receive clonidine (N=61) or placebo (N=57) for 14 weeks. Urine was tested thrice weekly. Lapse was defined as any opioid-positive or missed urine test, and relapse as two or more consecutive lapses. Time to lapse and relapse were examined with Cox regressions; longest period of abstinence was examined with a t test, and ecological momentary assessment data were examined with generalized linear mixed models.

RESULTS

In an intent-to-treat analysis, clonidine produced the longest duration (in consecutive days) of abstinence from opioids during the intervention phase (34.8 days [SD=3.7] compared with 25.5 days [SD=2.7]; Cohen's d=0.38). There was no group difference in time to relapse, but the clonidine group took longer to lapse (hazard ratio=0.67, 95% CI=0.45-1.00). Ecological momentary assessment showed that daily-life stress was partly decoupled from opioid craving in the clonidine group, supporting the authors' hypothesized mechanism for clonidine's benefits.

CONCLUSIONS

Clonidine, a readily available medication, is useful in opioid dependence not just for reduction of withdrawal signs, but also as an adjunctive maintenance treatment that increases duration of abstinence. Even in the absence of physical withdrawal, it decouples stress from craving in everyday life.

No evidence for reduction of opioid-withdrawal symptoms by cannabis smoking during a methadone dose taper

BACKGROUND AND OBJECTIVES

To support medication development with cannabinoids, smoked cannabis has been said to alleviate symptoms of opioid withdrawal. We evaluated that hypothesis.

METHODS

We analyzed data from the methadone-taper phase of a clinical trial we had conducted. Participants were 116 outpatient heroin and cocaine users (of whom 46 were also cannabis users) who stayed for the 10-week taper. Main outcome measures were weekly urine screens for cannabinoids, plus every-two-week assessments of opioid-withdrawal symptoms.

RESULTS

Opioid-withdrawal scores did not differ overall between users and nonusers of cannabis. In a lagged analysis in the 46 users, there was a slight (not statistically significant) indication that weeks of higher opiate-withdrawal symptoms preceded weeks of cannabis use (effect-size r = .20, 95% CI -.10 to .46, p = .52). Even if this finding is taken to suggest self-medication with cannabis, a lagged analysis in the other temporal direction showed no indication that cannabis use predicted lower opiate-withdrawal symptoms the next week (effect-size r = .01, 95% CI -.28 to .30, p = .69). These findings persisted in sensitivity analyses controlling for each of 17 potential confounds.

DISCUSSION AND CONCLUSION

With our findings, the clinical evidence for smoked cannabis as a reducer of opioid-withdrawal symptoms moves slightly further from "inconclusive" or "mixed" and closer to negative, at least in the context of a methadone dose taper like the one used here.

SCIENTIFIC SIGNIFICANCE

This finding may remove one rationale for medication development using cannabinoids to treat opioid withdrawal, but leaves other rationales intact.

Substance use and hepatitis C: an ecological momentary assessment study

OBJECTIVE

The objective of this study was to assess craving and mood related to opioid and cocaine use among asymptomatic hepatitis C virus (HCV)+ and HCV- methadone patients who have not started antiviral treatment.

METHODS

In this 28-week prospective ecological momentary assessment (EMA) study, 114 methadone-maintained, heroin- and cocaine-abusing individuals reported from the field in real time on their mood, craving, exposure to drug-use triggers, and drug use via handheld computers.

RESULTS

Sixty-one percent were HCV+; none were overtly symptomatic or receiving HCV treatment. HCV status was not associated with age, sex, race, or past-30-day or lifetime heroin or cocaine use. In event-contingent EMA entries, HCV+ individuals more often attributed use to having been bored, worried, or sad; feeling uncomfortable; or others being critical of them compared with HCV- participants. In randomly prompted EMA entries, HCV+ participants reported significantly more exposure to drug-use triggers, including handling ≥$10, seeing cocaine or heroin, seeing someone being offered/use cocaine or heroin, being tempted to use cocaine, and wanting to see what would happen if they used just a little cocaine or heroin.

CONCLUSIONS

HCV+ individuals experienced more negative moods and more often cited these negative moods as causes for drug use. HCV+ individuals reported greater exposure to environmental drug-use triggers, but they did not more frequently cite these as causes for drug use. The EMA data reported here suggest that HCV+ intravenous drug users may experience more labile mood and more reactivity to mood than HCV- intravenous drug users. The reason for the difference is not clear, but HCV status may be relevant to tailoring of treatment.

Are We There Yet? Feasibility of Continuous Stress Assessment via Wireless Physiological Sensors

Stress can lead to headaches and fatigue, precipitate addictive behaviors (e.g., smoking, alcohol and drug use), and lead to cardiovascular diseases and cancer. Continuous assessment of stress from sensors can be used for timely delivery of a variety of interventions to reduce or avoid stress. We investigate the feasibility of continuous stress measurement via two field studies using wireless physiological sensors - a four-week study with illicit drug users (n = 40), and a one-week study with daily smokers and social drinkers (n = 30). We find that 11+ hours/day of usable data can be obtained in a 4-week study. Significant learning effect is observed after the first week and data yield is seen to be increasing over time even in the fourth week. We propose a framework to analyze sensor data yield and find that losses in wireless channel is negligible; the main hurdle in further improving data yield is the attachment constraint. We show the feasibility of measuring stress minutes preceding events of interest and observe the sensor-derived stress to be rising prior to self-reported stress and smoking events.

Daily temporal patterns of heroin and cocaine use and craving: relationship with business hours regardless of actual employment status

Real-time monitoring of behavior using Ecological Momentary Assessment (EMA) has provided detailed data about daily temporal patterns of craving and use in cigarette smokers. We have collected similar data from a sample of cocaine and heroin users. Here we analyzed it in the context of its relationship with a societal construct of daily temporal organization: 9-to-5 business hours. In a 28-week prospective study, 112 methadone-maintained polydrug-abusing individuals initiated an electronic-diary entry and provided data each time they used cocaine, heroin, or both during weeks 4 to 28. EMA data were collected for 10,781 person-days and included: 663 cocaine-craving events, 710 cocaine-use events, 288 heroin-craving events, 66 heroin-use events, 630 craving-both-drugs events, and 282 use-of-both-drugs events. At baseline, 34% of the participants reported full-time employment in the preceding 3-year period. Most participants' current employment status fluctuated throughout the study. In a generalized linear mixed model (SAS Proc Glimmix), cocaine use varied by time of day relative to business hours (p<0.0001) and there was a significant interaction between Day of the Week and Time Relative to Business Hours (p<0.002) regardless of current work status. Cocaine craving also varied by time of day relative to business hours (p<0.0001), however, there was no significant interaction between Day of the Week and Time Relative to Business Hours (p=.57). Heroin craving and use were mostly reported during business hours, but data were sparse. Cocaine craving is most frequent during business hours while cocaine use is more frequent after business hours. Cocaine use during business hours, but not craving, seems suppressed on most weekdays, but not weekends, suggesting that societal conventions reflected in business hours influence drug-use patterns even in individuals whose daily schedules are not necessarily dictated by employment during conventional business hours.

Cardiac complications of unwitting co-injection of quinine/quinidine with heroin in an intravenous drug user

Adulterants "cut into" street heroin are common and often not detected by standard urine toxicology screening; however, their unwitting co-injection may have clinical consequences. We report a case of accelerated atrioventricular junctional arrhythmia that we determined to have been caused by quinine/quinidine cut into heroin. While identification and discontinuation of the offending agent helps confirm the diagnosis and is the treatment of choice, this is often complicated by the individual's dependence on the street drug in which the adulterant is mixed. This case highlights the need for clinicians to be aware of common adulterants, to know how to test for them, and to consider them as possible causes of medical complications in individuals who use drugs.

Opioid challenge evaluation of blockade by extended-release naltrexone in opioid-abusing adults: dose-effects and time-course

BACKGROUND

Oral naltrexone's effectiveness as an opioid antagonist has been limited due to poor patient adherence. A long-acting naltrexone formulation may be beneficial. This study evaluated the effects of extended-release injectable naltrexone (XR-NTX), targeted for a one-month duration of action, in blocking opioid agonist challenge effects in humans.

METHODS

Outpatient non-dependent opioid abusers (N=27) were randomly assigned to a single double-blind IM administration of 75, 150, or 300 mg XR-NTX. To assess the extent of opioid blockade, hydromorphone challenges (0, 3, 4.5, 6 mg IM in ascending order at 1-h intervals [up to 13.5 mg total]) were given at pretreatment baseline and on days 7, 14, 21, 28, 42, and 56. Opioid blockade was assessed via (1) tolerability of the ascending hydromorphone doses; (2) visual analog scale (VAS) ratings of subjective opioid effects and (3) pupil diameter. Effects on the VAS and pupils were assessed via the slope of the time-action function over ascending hydromorphone doses, with zero slope indicating complete blockade.

RESULTS

Blockade of the VAS "any drug effect" response to 3 mg hydromorphone was complete for 14, 21, and 28 days, respectively, for the XR-NTX doses of 75, 150, and 300 mg. Subjective effects were more readily blocked than was pupil constriction. Higher hydromorphone doses produced only modest increases in agonist effects. With the 300 mg XR-NTX dose the slope of VAS responses remained at or near zero for one month even with maximal cumulative hydromorphone dosing.

CONCLUSIONS

These data quantify the month-long opioid blockade underlying XR-NTX's efficacy in opioid dependence treatment.

TGI Monday?: drug-dependent outpatients report lower stress and more happiness at work than elsewhere

In the general population, experience-sampling studies show that work is the aspect of daily life most associated with momentary unhappiness and a desire to be elsewhere. We assessed whether this holds true for urban outpatients in treatment for heroin and cocaine dependence. In a 25-week natural-history study, 79 employed methadone-maintained misusers of heroin and cocaine carried electronic diaries on which mood and behavior were assessed up to five times per day. Being at work was associated with lower stress, greater happiness, and lower drug craving. Work accounted for 14% of the variance in stress, 30% of the variance in happiness, and 50% of the variance in cocaine craving. Participants with skilled jobs reported more positive and less negative mood states (and lower cocaine craving) at all times compared to participants with semi/unskilled jobs, although the latter reported greater mood improvement at work. In all participants, mood improvements occurred specifically in the presence of coworkers (not other companions). Our seemingly unusual findings might be specific to substance-disorder patients (for whom work may be a respite from drug-using companions), but might also hold for other urban dwellers of similar socioeconomic backgrounds (for whom work may be a respite from environmental stressors).

Primary outcome indices in illicit drug dependence treatment research: systematic approach to selection and measurement of drug use end-points in clinical trials

AIMS

Clinical trials test the safety and efficacy of behavioral and pharmacological interventions in drug-dependent individuals. However, there is no consensus about the most appropriate outcome(s) to consider in determining treatment efficacy or on the most appropriate methods for assessing selected outcome(s). We summarize the discussion and recommendations of treatment and research experts, convened by the US National Institute on Drug Abuse, to select appropriate primary outcomes for drug dependence treatment clinical trials, and in particular the feasibility of selecting a common outcome to be included in all or most trials.

METHODS

A brief history of outcomes employed in prior drug dependence treatment research, incorporating perspectives from tobacco and alcohol research, is included. The relative merits and limitations of focusing on drug-taking behavior, as measured by self-report and qualitative or quantitative biological markers, are evaluated.

RESULTS

Drug-taking behavior, measured ideally by a combination of self-report and biological indicators, is seen as the most appropriate proximal primary outcome in drug dependence treatment clinical trials.

CONCLUSIONS

We conclude that the most appropriate outcome will vary as a function of salient variables inherent in the clinical trial, such as the type of intervention, its target, treatment goals (e.g. abstinence or reduction of use) and the perspective being taken (e.g. researcher, clinical program, patient, society). It is recommended that a decision process, based on such trial variables, be developed to guide the selection of primary and secondary outcomes as well as the methods to assess them.