Addiction research centres and the nurturing of creativity. The Centre for Alcohol and Drug Research: social science alcohol and drug research in Denmark

Aims The purpose of this paper is to introduce the social science alcohol and drug research undertaken by the Centre for Alcohol and Drug Research (CRF) and at the same time offer an insight into the development in Danish alcohol and drug research throughout the past 15–20 years. Method A review of articles, books and reports published by researcher from CRF from the mid‐1990s until today and an analysis of the policy‐making in the Danish substance use and misuse area. Results CRF is a result of the discussions surrounding social, health and allocation policy questions since the mid‐1980s. Among other things, these discussions led to the formal establishment of the Centre in 1991 under the Aarhus University, the Faculty of Social Science. Since 2001 the Centre has received a permanent basic allocation, which has made it possible to appoint tenured senior researchers; to work under a more long‐term research strategy; to function as a milieu for educating PhD students; and to diversify from commissioned research tasks to initiating projects involving more fundamental research. Research at the Centre is today pivoted around four core areas: consumption, policy, prevention and treatment. Conclusion The emergence, continuation, financing and character of the research taking place at CRF can be linked closely to the specific Danish drug and alcohol discourse and to the division of the responsibility for alcohol and drug research into separate Ministries.     

A social network perspective on heroin and cocaine use among adults: evidence of bidirectional influences

Aims   While several studies have documented a relationship between initiation of drug use and social network drug use in youth, the direction of this association is not well understood, particularly among adults or for stages of drug involvement beyond initiation. The present study sought to examine two competing theories (social selection and social influence) in the longitudinal relationship between drug use (heroin and/or cocaine) and social network drug use among drug-experienced adults.
Design   Three waves of data came from a cohort of 1108 adults reporting a life-time history of heroin and/or cocaine use.
Setting   Low-income neighborhoods with high rates of drug use in Baltimore, Maryland.
Participants   Participants had weekly contact with drug users and were 18 years of age or older.
Measurements   Drug use data were self-report. Network drug use was assessed through a social network inventory. Close friends were individuals whom the participant reported seeing daily or rated as having the highest level of trust.
Findings   Structural equation modeling indicated significant bidirectional influences. The majority of change in network drug use over time was due to change in the composition of the network rather than change in friends' behavior. Drug use by close peers did not influence participant drug use beyond the total network.
Conclusions   There is evidence of both social selection and social influence processes in the association between drug use and network drug use among drug-experienced adults.     

Social integration in young adulthood and the subsequent onset of substance use and disorders among a community population of urban African Americans

Aims This paper examines the association between social integration in young adulthood and the later onset of substance use and disorders through mid‐adulthood. Design Data come from a community cohort of African Americans followed longitudinally from age 6–42 years with four assessment periods. Setting The cohort all lived in the Woodlawn neighborhood of Chicago in 1966, an urban disadvantaged setting. Participants All Woodlawn first graders in 1966 were asked to participate; 13 families declined (n = 1242). Measurement Substance use was measured via interview at age 42 and includes the onset of alcohol and drug use disorders and the onset of cocaine/heroin use between ages 32 and 42 years. Social integration measures were assessed via interview at age 32 and include social roles (employee, spouse, parent), participation in religious and social organizations and a measure of overall social integration. Control variables were measured in childhood and later in the life course. Findings Multivariate regression analyses suggest that unemployment, being unmarried, infrequent religious service attendance and lower overall social integration in young adulthood predict later adult‐onset drug use disorders, but not alcohol use disorders once confounders are taken into consideration. Unemployment and lower overall social integration predict onset of cocaine/heroin use later in adulthood. Conclusions Results show meaningful onset of drug use and substance use disorders during mid‐adulthood and that social integration in young adulthood seems to play a role in later onset of drug use and drug disorders, but not alcohol disorders.     

The added risk of opioid problem use among treatment‐seeking youth with marijuana and/or alcohol problem use

Objectives To determine the added risk of opioid problem use (OPU) in youth with marijuana/alcohol problem use (MAPU). Methods A total of 475 youth (ages 14–21 years) with OPU + MAPU were compared to a weighted sample of 475 youth with MAPU only (i.e. no OPU) before and after propensity score matching on gender, age, race, level of care and weekly use of marijuana/alcohol. Youth were recruited from 88 drug treatment sites participating in eight Center for Substance Abuse Treatment‐funded grants. At treatment intake, participants were administered the Global Appraisal of Individual Need to elicit information on demographic, social, substance, mental health, human immunodeficiency virus (HIV), physical and legal characteristics. Odds ratios with confidence intervals were calculated. Results The added risk of OPU among MAPU youth was associated with greater comorbidity; higher rates of psychiatric symptoms and trauma/victimization; greater needle use and sex‐related HIV risk behaviours; and greater physical distress. The OPU + MAPU group was less likely to be African American or other race and more likely to be aged 15–17 years, Caucasian; report weekly drug use at home and among peers; engage in illegal behaviors and be confined longer; have greater substance abuse severity and polydrug use; and use mental health and substance abuse treatment services. Conclusions These findings expand upon the existing literature and highlight the substantial incremental risk of OPU on multiple comorbid areas among treatment‐seeking youth. Further evaluation is needed to assess their outcomes following standard drug treatment and to evaluate specialized interventions for this subgroup of severely impaired youth.     

Impact of Nursing Intervention on Decreasing Substances among Homeless Youth

Background : Alcohol use, and in particular, binge drinking, and methamphetamine use is pervasive among homeless youth and remains a social pressure among this vulnerable population. However, there is no compelling evidence that specific interventions for reducing drug and alcohol use are effective for homeless youth. Objectives : This community‐based participatory action pilot study assessed the impact of an intervention study focused on decreasing use of drugs and alcohol among a sample of homeless young adults (N= 154) visiting a drop‐in site in Santa Monica, California. The two programs consisted of an HIV/AIDS and Hepatitis Health Promotion (HHP) program led by nurses and an Art Messaging (AM) program led by artists. Six‐month follow‐up data were obtained from 100 of these individuals. Results : Findings revealed significant reductions in alcohol and marijuana use and binge drinking in both the HHP and AM programs. However, homeless youth in the HHP program reported additional reductions in methamphetamine, cocaine, and hallucinogen use at 6‐month follow‐up. Conclusions : Reductions in drugs and alcohol are important as these substances are linked to HIV/AIDS, hepatitis, and other health risks in homeless youth. Scientific Significance : The successful outcomes of the study intervention validate the utility of nurse‐led and artistic health promotion strategies to decrease drug and alcohol use and other risky behaviors in homeless youth populations. (Am J Addict 2012;21:558–565)     

The relevance of the content of an HIV and AIDS social intervention programme for the youth in the Northern Cape,South Africa

The numbers of people infected with HIV and living with AIDS remain high in South Africa. The youth of the Northern Cape province in South Africa are a vulnerable population in this regard. However, there seems to be a dearth of rigorous evaluations of HIV and AIDS social intervention programmes targeted at the youth. This study aimed to evaluate the relevance of the content of an HIV and AIDS social intervention programme for the youth in the Northern Cape as well as to collect attendees’ recommendations with regards to programme content. The data collection method comprised a group-administered questionnaire completed by youth (N = 172) who participated in the Soul City social intervention programme (SCP) implemented for the youth in the Northern Cape, and recruited through stratified random sampling. Based on specific criteria, the results showed that the SCP programme’s content was relevant to the communities it served. The youth also forwarded recommendations for the programme content. Recommendations from the study include that youth support should be beyond dialogues; women’s rights should be promoted within the context of HIV prevention strategies; the SCP should intensify its condom promotion efforts because it is relevant to the South African government’s macro-level plan; relevant community leaders should be visited to explain the rationale for the youth’s involvement in programmes; and the programme should focus more pertinently on poverty alleviation strategies.     

Orthogonal cultural identification theory: the cultural identification of minority adolescents

A theory of cultural identification is presented indicating that identification with different cultures is orthogonal. Instead of cultures being placed at opposite ends of a continuum, cultural identification dimensions are independent of each other, and increasing identification with one culture does not require decreasing identification with another. Studies of Native-American and Mexican-American youth show that: (1) identification with Anglo (White American) culture is related to having Anglo friends and to family acceptance of an Anglo marriage, (2) identification with either the minority or the majority culture is a source of personal and social strength, and (3) this greater strength, however, does not translate automatically into less drug use, because drug use is related to how much the culture that the person identifies with approves or disapproves of drugs.     

Long-term consequences of adolescent cannabis use: Examining intermediary processes

Background: In the United States, perceptions of marijuana’s acceptability are at an all-time high, risk perceptions among youth are low, and rates are rising among Black youth. Thus, it is imperative to increase the understanding of long-term effects of adolescent marijuana use and ways to mitigate adverse consequences. Objectives: To identify the midlife consequences of heavy adolescent marijuana use and the mechanisms driving effects among a Black, urban population. Methods: This study analyzed the propensity score-matched prospective data from the Woodlawn Study, a community cohort study of urban Black youth followed from ages 6–42. After matching the 165 adolescents who used marijuana heavily to 165 non-heavy/nonusers on background confounders to reduce selection effects (64.5% male), we tested the association of heavy marijuana use by age 16 with social, economic, and physical and psychological health outcomes in midlife and the ability of adult drug trajectories (marijuana, cocaine, and heroin use from ages 17–42) and school dropout to mediate effects. Results: Heavy adolescent marijuana use was associated with an increased risk of being poor and of being unmarried in midlife. Marijuana use also predicted lower income and greater anxious mood in midlife. Both adult drug use trajectories and school dropout significantly mediated socioeconomic effects but not marital or anxious mood outcomes. Conclusion: Heavy adolescent marijuana use seems to set Black, urban youth on a long-term trajectory of disadvantage that persists into midlife. It is critical to interrupt this long-term disadvantage through the prevention of heavy adolescent marijuana use, long-term marijuana and other drug use, and school dropout.     

Cessation from cocaine use

This study explores factors that are related to cessation of cocaine use versus continued use in a non-clinical sample of American adolescents and young adults interviewed at three points in time. At time 3, cocaine stoppers (n= 104) and current users (n= 267) are compared in terms of age and sex, patterns of contemporary and prior drug use, life-style characteristics and a selected group of social learning variables. The data indicate that cocaine stoppers and users have similar patterns of alcohol, marijuana, cigarette, cocaine and other drug use at time 1 and time 2, but that users have higher time 3 frequencies of alcohol, marijuana and other drug use. In addition, those youth who stop are more likely to be married and have children, although the groups do not differ in terms of career/school, status. The data lend partial support to a social learning perspective and indicate that differential associations (friends' use) and punishments (negative consequences) are most strongly related to cessation. In addition, users report more dependency symptoms than do stoppers.     

How important is treatment? One‐year outcomes of treated and untreated alcohol‐dependent individuals

Aims To compare representative treatment and untreated samples of alcohol‐dependent individuals in rates of abstinence and non‐problematic use at 1‐year follow‐up. Participants and design A total of 482 alcohol‐dependent adults in a northern California county identified through a probability survey of problem drinkers in the general population (n = 111) or a survey of consecutive admissions to public and private substance abuse programs (n = 371) were interviewed in person at baseline and by telephone at 1 year. Measurements Logistic regression models were used to predict 30‐day abstinence and 12‐month non‐problematic alcohol use. Results At follow‐up, alcohol‐dependent individuals in the treatment sample had higher abstinence rates and non‐problematic use outcomes than those in the untreated general population sample. In logistic regression models of the merged samples, being in the treatment sample was related strongly and positively to abstinence and non‐problematic use. Having more drug users and heavy drinkers in one's social network, higher psychiatric comorbidity, and more social consequences were inversely related to abstinence and non‐problematic use in the treatment sample. The number of drug users and heavy drinkers in one's social network was also inversely related to abstinence in both the treatment and untreated general population samples. Results predicting non‐problematic use were similar. Conclusions These results are consistent with other studies that examine treatment effectiveness in the absence of a controlled trial. Although natural recovery also occurs, alcohol‐dependent individuals benefit from treatment. Co‐occurring psychiatric problems continue to be major barriers to treatment effectiveness. An emphasis on changing social networks to be conducive to recovery could heighten both clinical effectiveness and prevention efforts within communities.     

Rediscovering MDMA (ecstasy): the role of the American chemist Alexander T. Shulgin

Aims Alexander T. Shulgin is widely thought of as the ‘father’ of +/?3,4‐methylenedioxymethamphetamine (MDMA). This paper re‐assesses his role in the modern history of this drug. Methods We analysed systematically Shulgin's original publications on MDMA, his publications on the history of MDMA and his laboratory notebook. Results According to Shulgin's book PIHKAL (1991), he synthesized MDMA in 1965, but did not try it. In the 1960s Shulgin also synthesized MDMA‐related compounds such as 3,4‐methylenedioxyamphetamine (MDA), 3‐methoxy‐4,5‐methylenedioxyamphetamine (MMDA) and 3,4‐methylenedioxyethylamphetamine (MDE), but this had no impact on his rediscovery of MDMA. In the mid‐1970s Shulgin learned of a ‘special effect’ caused by MDMA, whereupon he re‐synthesized it and tried it himself in September 1976, as confirmed by his laboratory notebook. In 1977 he gave MDMA to Leo Zeff PhD, who used it as an adjunct to psychotherapy and introduced it to other psychotherapists. Conclusion Shulgin was not the first to synthesize MDMA, but he played an important role in its history. It seems plausible that he was so impressed by its effects that he introduced it to psychotherapist Zeff in 1977. This, and the fact that in 1978 he published with David Nichols the first paper on the pharmacological action of MDMA in humans, explains why Shulgin is sometimes (erroneously) called the ‘father’ of MDMA.     

Ketamine use: a review

Aims Ketamine remains an important medicine in both specialist anaesthesia and aspects of pain management. At the same time, its use as a recreational drug has spread in many parts of the world during the past few years. There are now increasing concerns about the harmful physical and psychological consequences of repeated misuse of this drug. The aim of this review was to survey and integrate the research literature on physical, psychological and social harms of both acute and chronic ketamine use. Method The literature on ketamine was systematically searched and findings were classified into the matrix of Nutt et al.'s (2007) rational scale for assessing the harms of psychoactive substances. Results A major physical harm is ketamine induced ulcerative cystitis which, although its aetiology is unclear, seems particularly associated with chronic, frequent use of the drug. Frequent, daily use is also associated with neurocognitive impairment and, most robustly, deficits in working and episodic memory. Recent studies suggest certain neurological abnormalities which may underpin these cognitive effects. Many frequent users are concerned about addiction and report trying but failing to stop using ketamine. Conclusions The implications of these findings are drawn out for treatment of ketamine‐induced ulcerative cystitis in which interventions from urologists and from addiction specialists should be coordinated. Neurocognitive impairment in frequent users can impact negatively upon achievement in education and at work, and also compound addiction problems. Prevention and harm minimization campaigns are needed to alert young people to these harmful and potentially chronic effects of ketamine.     

Treating adolescent drug abuse: a randomized trial comparing multidimensional family therapy and cognitive behavior therapy

Aim To examine the efficacy of two adolescent drug abuse treatments: individual cognitive behavioral therapy (CBT) and multidimensional family therapy (MDFT). Design A 2 (treatment condition) x 4 (time) repeated‐measures intent‐to‐treat randomized design. Data were gathered at baseline, termination, 6 and 12 months post‐termination. Analyses used latent growth curve modeling. Setting Community‐based drug abuse clinic in the northeastern United States. Participants A total of 224 youth, primarily male (81%), African American (72%), from low‐income single‐parent homes (58%) with an average age of 15 years were recruited into the study. All youth were drug users, with 75% meeting DSM‐IV criteria for cannabis dependence and 13% meeting criteria for abuse. Measurements Five outcomes were measured: (i) substance use problem severity; (ii) 30‐day frequency of cannabis use; (iii) 30‐day frequency of alcohol use; (iv) 30‐day frequency of other drug use; and (v) 30‐day abstinence. Findings Both treatments produced significant decreases in cannabis consumption and slightly significant reductions in alcohol use, but there were no treatment differences in reducing frequency of cannabis and alcohol use. Significant treatment effects were found favoring MDFT on substance use problem severity, other drug use and minimal use (zero or one occasion of use) of all substances, and these effects continued to 12 months following treatment termination. Conclusion Both interventions are promising treatments. Consistent with previous controlled trials, MDFT is distinguished by the sustainability of treatment effects.     

Drug use patterns and infection with sexually transmissible agents among young adults in a high-risk neighbourhood in New York City

Aims To determine relationships between drug use ‘hardness’ (defined in increasing order of hardness as no drug use, marijuana use, non‐injected heroin or cocaine use, crack smoking and injection drug use) and prevalences of several sexually transmissible infections among young adults in a high‐risk neighbourhood. Drug users, particularly injection drug users and crack smokers, may be a core group for some sexually transmitted infections. Design Cross‐sectional survey and assays of young adults from (a) a household probability sample and (b) a targeted sample of youth who have used injected drugs, crack, other cocaine or heroin. Setting Bushwick, an impoverished New York City minority neighbourhood with major drug markets. Participants A total of 363 18–24‐year‐olds from a household probability sample; 165 Bushwick 18–24‐year‐olds who have used injected drugs, crack, other cocaine or heroin. Measurements Drug use by self‐report; serum‐ and urine‐based assays for HIV, hepatitis B and C, syphilis, gonorrhoea, chlamydia and herpes simplex (type 2). Findings Household‐sample prevalences: HIV, hepatitis C and syphilis, 1%; gonorrhoea 3%; chlamydia 5%; past or present hepatitis B infection 8%; herpes simplex (type 2) 18%. In combined household and targeted samples, hepatitis C and HIV were concentrated among drug injectors. Herpes simplex (type 2), syphilis and hepatitis B increased among women with ‘hardest drug ever used’. Conclusions Using ‘harder’ drugs is associated with some but not all of these infections. Prevention efforts should help youth avoid unsafe sex and higher‐risk drugs.     

Shyness,social anxiety,social anxiety disorder,and substance use among normative adolescent populations: A systematic review

Researchers have increasingly studied shyness, social anxiety, and social anxiety disorder (SAD) as potential precursors of substance use. Objectives. The objective of this study was to review the relationships between these variables and tobacco use, alcohol use, and cannabis/drug use in normative adolescent populations and the extent to which these associations differ by gender. Methods. A systematic search in PsycINFO and PubMed was conducted, reference screening was performed, and five experts were consulted. Results. Fifty articles published between 1980 and 2016 were included for review. Shyness was frequently associated with lower use of tobacco, alcohol, and cannabis/drug. Similar findings emerged for social anxiety. In contrast, SAD tended to be associated with higher use of tobacco and cannabis/drug, although the association between SAD and the use of alcohol appeared inconclusive. Furthermore, limited evidence suggests that shy females use less tobacco than shy males and that males with social anxiety use less drugs than socially anxious females. Conclusions. In conclusion, these results highlight that shyness, social anxiety, and SAD may exert different effects on substance use. Higher use of substances among adolescents suffering from a SAD may be explained, among other possibilities, by a self-medication mechanism. While all adolescents should benefit from prevention efforts targeted at substance use, a systematic screening for substance use disorders during the clinical evaluation that precedes SAD treatments is advised.     

Crystal methamphetamine initiation among street-involved youth

Background: Although many settings have recently documented a substantial increase in the use of methamphetamine-type stimulants, recent reviews have underscored the dearth of prospective studies that have examined risk factors associated with the initiation of crystal methamphetamine use. Objectives: Our objectives were to examine rates and risk factors for the initiation of crystal methamphetamine use in a cohort of street-involved youth. Methods: Street-involved youth in Vancouver, Canada, were enrolled in a prospective cohort known as the At-Risk Youth Study (ARYS). A total of 205 crystal methamphetamine-naïve participants were assessed semi-annually and Cox regression analyses were used to identify factors independently associated with the initiation of crystal methamphetamine use. Results: Among 205 youth prospectively followed from 2005 to 2012, the incidence density of crystal methamphetamine initiation was 12.2 per 100 person years. In Cox regression analyses, initiation of crystal methamphetamine use was independently associated with previous crack cocaine use (adjusted relative hazard [ARH]?=?2.24 [95% CI: 1.20–4.20]) and recent drug dealing (ARH?=?1.98 [95% CI: 1.05–3.71]). Those initiating methamphetamine were also more likely to report a recent nonfatal overdose (ARH?=?3.63 [95% CI: 1.65–7.98]) and to be male (ARH?=?2.12 [95% CI: 1.06–4.25]). Conclusions: We identified high rates of crystal methamphetamine initiation among this population. Males those involved in the drug trade, and those who used crack cocaine were more likely to initiate crystal methamphetamine use. Evidence-based strategies to prevent and treat crystal methamphetamine use are urgently needed.     

Recovery Capital and Social Networks Among People in Treatment and Among Those in Recovery in York,England

Recovery has been associated with a transition in social networks and peer influences in terms of moving away from using peers and engaging in social networks, including those in recovery. This article uses a quantitative data approach to compare a group of individuals who described themselves as in recovery from alcohol and other drug (AOD) problems with a group from the same city involved in alcohol and drug treatment. The measures used included social network involvement and an assessment of recovery capital. Those in recovery had more people in recovery in their social networks, fewer people in active use in their networks, and were much more likely to be involved in formal recovery support groups. They also reported higher quality of life, lower depression and anxiety, and higher levels of personal and social capital. The groups hardly overlapped at all in their functioning, and one of the major challenges of a recovery model will be reconciling the positive recovery networks and cultures of recovery with the narrower and less recovery focused world of many users of structured treatment services. Understanding the mechanisms for the transition from using to recovery communities is essential to understanding a core component of the recovery journey.     

From the Cover: Functional changes of the reward system underlie blunted response to social gaze in cocaine users

Social interaction deficits in drug users likely impede treatment, increase the burden of the affected families, and consequently contribute to the high costs for society associated with addiction. Despite its significance, the neural basis of altered social interaction in drug users is currently unknown. Therefore, we investigated basal social gaze behavior in cocaine users by applying behavioral, psychophysiological, and functional brain-imaging methods. In study I, 80 regular cocaine users and 63 healthy controls completed an interactive paradigm in which the participants’ gaze was recorded by an eye-tracking device that controlled the gaze of an anthropomorphic virtual character. Valence ratings of different eye-contact conditions revealed that cocaine users show diminished emotional engagement in social interaction, which was also supported by reduced pupil responses. Study II investigated the neural underpinnings of changes in social reward processing observed in study I. Sixteen cocaine users and 16 controls completed a similar interaction paradigm as used in study I while undergoing functional magnetic resonance imaging. In response to social interaction, cocaine users displayed decreased activation of the medial orbitofrontal cortex, a key region of reward processing. Moreover, blunted activation of the medial orbitofrontal cortex was significantly correlated with a decreased social network size, reflecting problems in real-life social behavior because of reduced social reward. In conclusion, basic social interaction deficits in cocaine users as observed here may arise from altered social reward processing. Consequently, these results point to the importance of reinstatement of social reward in the treatment of stimulant addiction.Cocaine dependence is a chronically relapsing disorder defined by uncontrolled and compulsive drug use (1). Despite severe negative consequences including disrupted social relationships, loss of employment, and somatic and psychiatric illnesses, an addicted person’s life is often centered around the drug of choice and activities related to it (2). Therefore, drug use is classified as a major social, legal, and public health problem (3). After cannabis, cocaine is the second most prevalent illegal drug in the United States and Europe (4, 5), with a lifetime prevalence among young adults of 6.3% in Europe (15- to 34-y-olds) (4) and 13.3% in the United States (18- to 25-y-olds) (5).Social cognition and social support for drug users are of great clinical relevance, as they have been reported to influence onset of drug use and development of substance use disorders, and treatment success in patients with substance use disorders (6, 7). Impairments in social cognition may augment the risk of social isolation, aggression, and depression, likely supporting the vicious circle of drug use (8). Additionally, impaired social cognition may contribute to the decay of social relationships in addicted patients (9) with negative consequences for treatment success given that higher social support predicted longer abstinence duration (10). Furthermore, no efficient pharmacological treatment for cocaine addiction is currently available (11), and treatment approaches such as cognitive behavioral therapy rely, at least in part, on the emotional responsiveness and social abilities of drug users (12). Previous results suggest that cocaine users (CUs) show impairments in different facets of social cognition, particularly in emotional empathy, mental perspective taking, and emotion recognition in prosody, which are related to deficits in real-life social behavior such as fewer social contacts and more criminal offenses (13, 14). Furthermore, in money distribution games, CUs act more self-servingly and less altruistically than stimulant-naïve controls (15). Volkow et al. (9) postulated that neuroadaptations in the reward systems of drug users (e.g., ventral striatum and orbitofrontal cortex) alter reward processing such that the value of the abused drug is enhanced and concurrently the value of nondrug rewards, including social interaction, is reduced. Consequently, general social competence might become impaired and promote antisocial and criminal behavior. This may explain why social consequences of drug use (e.g., imprisonment or familial problems) do not prompt drug-addicted people to quit using the drug as well as how they contribute to increased drug use and transition from recreational drug use to addiction (9). However, whereas altered processing of monetary rewards has been reported in CUs (16), social reward processing has not been studied yet, neither on the psychological nor the neural level. Therefore, it remains elusive whether CUs (i) show behavioral differences to reward stemming from social interactions and, if so, (ii) which neural adaptations within reward circuitry underlie these potential changes in social interaction behavior.An essential part of social interaction is the phenomenon of “social gaze,” which has two aspects: Gaze can be used by the gazing person as a deictic cue to manipulate the attention of others, and can be read out by observers as a hint toward attentional focus of the gazing person (17). Both aspects can converge in joint attention (JA), which is a central element of social interaction (18) and is established when a person follows the direction of another person’s gaze so that both attend to the same object (19). Engagement in JA is considered to reflect our understanding of another person’s point of view (20). The capacity of JA emerges at 8–12 mo of age (21) and is predictive for later language learning (22) and the development of more advanced social skills such as mental perspective taking (e.g., the attribution of intentions and goals to others, also known as theory of mind) (23). Impaired JA is a core symptom of autism spectrum disorders (24).To test for social gaze differences between CUs and healthy controls (HCs), we applied a paradigm designed to capture the reciprocal and interactive nature of JA (25) (Fig. S1), where participants engage in an online interaction with an anthropomorphic virtual character in real time. Compared with self-initiated nonjoint attention (NJA; i.e., if the counterpart does not follow one’s gaze but rather pays attention to another object), self-initiated JA (i.e., if the counterpart follows one’s own gaze) is perceived as more pleasurable and associated with stronger activation of reward-related brain areas in healthy controls (25). This rewarding nature of JA might underlie the human motivation to engage in the sharing of experiences that emerges in early childhood (22, 25).It has been suggested that changes in social reward processing might underlie alterations in social behavior and cognition in CUs (9). Here we conducted two studies assessing JA processing, which constitutes an elegant approach to investigate basic social interaction patterns related to social reward processing (25), in CUs and stimulant-naïve HCs by means of behavioral, psychophysiological, and functional brain-imaging methods. In study I, a large sample of relatively pure CUs with few psychiatric comorbidities (n = 80) and stimulant-naïve HCs (n = 63) completed an interactive JA task (25) while valence and arousal ratings, error scores, reaction time, and pupil size were obtained. Pupil dilation provides an objective index of affective processing (26, 27). Based on the observations obtained in study I, we further investigated the neural correlates of the blunted emotional response to social gaze in subsamples of 16 CUs and 16 HCs using functional magnetic resonance imaging (fMRI) during an abridged version of the paradigm (study II). We hypothesized that altered emotional responses to JA are accompanied by less pronounced activation in reward-related brain areas of CUs.     

Network‐based recruitment of people who inject drugs for hepatitis C testing and linkage to care

Although oral direct‐acting agent (DAA) therapies have the potential to reduce the burden of hepatitis C virus (HCV) infection, treatment uptake remains low, particularly among people who inject drugs (PWID). This study examined the feasibility of an innovative peer‐based recruitment strategy to engage PWID in HCV testing and treatment. We interviewed an initial set of HCV antibody‐positive PWID as ‘primary indexes’ to gather demographic, drug use, health information and drug network characteristics. Primary indexes were then briefly educated on HCV and its treatment and encouraged to recruit their injection drug ‘network members’ for HCV testing and linkage to care. Eligible network members were enrolled as ‘secondary indexes’ and completed the same index study procedures. In sum, 17 of 36 primary indexes initiated the recruitment of 64 network members who were HCV antibody positive and eligible to become indexes. In multivariable analysis, successful recruitment of at least one network member was positively associated with prior HCV treatment (OR 2.80; CI [1.01, 7.72]), daily or more injection drug use (OR 2.38; CI [1.04, 5.47]), and a higher number of injection drug network members (OR 1.20; CI [1.01, 1.42]). Among the 69 participants with chronic HCV not previously linked to HCV care at enrolment, 91% (n = 63) completed a linkage to HCV care appointment, 45% (n = 31) scheduled an appointment with an HCV provider, and 20% (n = 14) initiated HCV therapy. These findings suggest a potential benefit for peer‐driven, network‐based interventions focused on HCV treatment‐experienced PWID as a mechanism to increase HCV linkage to care.