Discriminative stimuli are sufficient for incubation of cocaine craving

In abstinent drug addicts, cues formerly associated with drug-taking experiences gain relapse-inducing potency ('incubate') over time. Animal models of incubation may help develop treatments to prevent relapse, but these models have ubiquitously focused on the role of conditioned stimuli (CSs) signaling drug delivery. Discriminative stimuli (DSs) are unique in that they exert stimulus-control over both drug taking and drug seeking behavior and are difficult to extinguish. For this reason, incubation of the excitatory effects of DSs that signal drug availability, not yet examined in preclinical studies, could be relevant to relapse prevention. We trained rats to self-administer cocaine (or palatable food) under DS control, then investigated DS-controlled incubation of craving, in the absence of drug-paired CSs. DS-controlled cocaine (but not palatable food) seeking incubated over 60 days of abstinence and persisted up to 300 days. Understanding the neural mechanisms of this DS-controlled incubation holds promise for drug relapse treatments.

Science-Based Actions Can Help Address the Opioid Crisis

The epidemic of addiction and overdose is real. Addiction among pain patients accounts for only a small proportion but a large number. Scientific opinion leaders can be most effective on two fronts, each relatively low-tech: dissemination and oversight of empirically established treatments, and promulgation of social-science-based strategies for population-level prevention.

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.

Real-time assessment of alcohol drinking and drug use in opioid-dependent polydrug users

We investigated relationships between drinking, other drug use, and drug craving, using ecological momentary assessment (EMA), in a sample of polydrug users who were not heavy drinkers. In a prospective longitudinal cohort study, 114 heroin and cocaine users on methadone-maintenance treatment carried handheld electronic diaries during waking hours and were screened for drug and alcohol use for up to 25 weeks. Individuals who fulfilled the Diagnostic and Statistical Manual of Mental Disorders criteria for alcohol abuse or dependence were excluded. Participants responded to 2-5 random prompts per day to report on their moods, cravings, and activities and initiated entries when they used or acutely craved heroin or cocaine. Drinking alcohol was assessed in both types of entries. Breath alcohol was measured three times weekly. Participants reported drinking alcohol in 1.6% of random-prompt entries, 3.7% of event-contingent entries when craving cocaine and/or heroin, and 11.6% of event-contingent entries when using cocaine and/or heroin. Alcohol drinking was also associated with higher craving ratings and prestudy alcohol use. More drinking was detected by ambulatory self-report than by in-clinic breath testing. Even though we had screened out heavy drinkers from our sample of polydrug users, drinking was associated with heroin and cocaine craving and actual use.

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.

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.

Gender differences in neural-behavioral response to self-observation during a novel fMRI social stress task

The neural correlates of response to psychosocial stress and gender differences therein are difficult to model experimentally as this type of stressor is difficult to induce in a brain imaging environment. The Trier Social Stress Test (TSST), a behavioral paradigm that reliably induces moderate levels of stress was thus modified for the MRI environment. To determine the neurobehavioral basis of gender differences in response to observing oneself under social evaluative stress, 26 subjects (14 females) performed the TSST while being videotaped. During fMRI scanning, subjects were shown alternating video clips of two

CONDITIONS

SELF or a same-sex OTHER performing the TSST. Subjects rated their stress level immediately after the video clips. GENDER differences in the [SELF-OTHER] contrast were analyzed. There was a GENDER×CONDITION interaction such that only women reported increased subjective stress during video feedback of their TSST session. A whole brain analysis (SELF vs. OTHER) showed activation in the bilateral insula, inferior, middle and superior frontal gyri. Greater recruitment was seen among males in some of these same areas in the context of significantly lower stress ratings. Activation of areas involved in inhibitory control and sensory awareness might contribute to the significantly lower stress ratings in males. Understanding these gender differences is relevant to disorders of stress and self-concept.

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.

A memory retrieval-extinction procedure to prevent drug craving and relapse

Drug use and relapse involve learned associations between drug-associated environmental cues and drug effects. Extinction procedures in the clinic can suppress conditioned responses to drug cues, but the extinguished responses typically reemerge after exposure to the drug itself (reinstatement), the drug-associated environment (renewal), or the passage of time (spontaneous recovery). We describe a memory retrieval-extinction procedure that decreases conditioned drug effects and drug seeking in rat models of relapse, and drug craving in abstinent heroin addicts. In rats, daily retrieval of drug-associated memories 10 minutes or 1 hour but not 6 hours before extinction sessions attenuated drug-induced reinstatement, spontaneous recovery, and renewal of conditioned drug effects and drug seeking. In heroin addicts, retrieval of drug-associated memories 10 minutes before extinction sessions attenuated cue-induced heroin craving 1, 30, and 180 days later. The memory retrieval-extinction procedure is a promising nonpharmacological method for decreasing drug craving and relapse during abstinence.

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).