Heroin Dependence Research Articles

Lee Robins' studies of heroin use among US Vietnam veterans

The work of Robins and her colleagues on heroin addiction among Vietnam veterans sets out in microcosm many of the key factors that play out in the development and maintenance of substance addiction beyond the pharmacology of the drug: price, availability, the process of delivery of the addictive substance, availability of other substances, social norms, education and life circumstances. Robins' studies found high rates of heroin use (34%) and symptoms of heroin dependence (20%) among US soldiers while serving in Vietnam. In the first year after returning to the United States only 1% became re-addicted to heroin, although 10% tried the drug after their return. Like other seminal studies, this work needs to be read in the original, because relying upon secondary interpretations risks being given a selectively edited version of their findings in service of varied policy and theoretical agendas.

Learning and generalization from reward and punishment in opioid addiction

This study adapts a widely-used acquired equivalence paradigm to investigate how opioid-addicted individuals learn from positive and negative feedback, and how they generalize this learning. The opioid-addicted group consisted of 33 participants with a history of heroin dependency currently in a methadone maintenance program; the control group consisted of 32 healthy participants without a history of drug addiction. All participants performed a novel variant of the acquired equivalence task, where they learned to map some stimuli to correct outcomes in order to obtain reward, and to map other stimuli to correct outcomes in order to avoid punishment; some stimuli were implicitly “equivalent” in the sense of being paired with the same outcome. On the initial training phase, both groups performed similarly on learning to obtain reward, but as memory load grew, the control group outperformed the addicted group on learning to avoid punishment. On a subsequent testing phase, the addicted and control groups performed similarly on retention trials involving previously-trained stimulus-outcome pairs, as well as on generalization trials to assess acquired equivalence. Since prior work with acquired equivalence tasks has associated stimulus-outcome learning with the nigrostriatal dopamine system, and generalization with the hippocampal region, the current results are consistent with basal ganglia dysfunction in the opioid-addicted patients. Further, a selective deficit in learning from punishment could contribute to processes by which addicted individuals continue to pursue drug use even at the cost of negative consequences such as loss of income and the opportunity to engage in other life activities.

Cost-effectiveness of center-based compulsory rehabilitation compared to community-based voluntary methadone maintenance treatment in Hai Phong City, Vietnam

IntroductionIn Vietnam, two dominant approaches for heroin treatment are center-based compulsory rehabilitation (CCT), funded by the Vietnamese government and community-based voluntary methadone maintenance treatment (MMT), funded primarily by international donors. Recent reduction in international funding requires more efficient allocation of government funding for public health programs. A cost-effectiveness analysis comparing two approaches provides a useful source of evidence to inform the government about funding reallocation. MethodsThe study was a combined retrospective and prospective, non-randomized cohort comparison over three years of CCT and MMT in Vietnam, conducted between 2012 and 2014, involving 208 CCT participants and 384 MMT participants with heroin dependence. The primary end-point was drug-free days over three years. Total costs, including both program and participant personal costs were measured and cost-effectiveness compared. Mixed effects regression analyses were used to analyze effectiveness data and non-parametric bootstrapping method was used to compare cost-effectiveness. ResultsOver three years, MMT costed on average VND85.73 million (US$4108) less than CCT (95% CI: -VND76.88 million, -VND94.59 million). On average, a MMT participant had 344.20 more drug-free days compared to a CCT participant (p<0.001). The incremental cost-effectiveness ratio for MMT was -VND0.25 million (US$11.99) (95% CI: -VND0.34 million, -VND0.19 million) per drug-free day suggesting MMT is the more cost effective alternative. ConclusionsCompared to CCT, MMT is both less expensive and more effective in achieving drug-free days. If the government of Vietnam invests in MMT instead of CCT, it is potentially a cost-saving strategy for reducing illicit drug use among heroin dependent individuals.

Variants of opioid system genes are associated with non-dependent opioid use and heroin dependence

BackgroundHeroin addiction is a chronic, relapsing brain disease. Genetic factors are involved in the development of drug addiction. The aim of this study was to determine whether specific variants in genes of the opioid system are associated with non-dependent opioid use and heroin dependence. MethodsGenetic information from four subject groups was collected: non-dependent opioid users (NOD) [n=163]; opioid-dependent (OD) patients in methadone maintenance treatment (MMT) [n=143]; opioid-dependent MMT-resistant patients in heroin-assisted treatment (HAT) [n=138]; and healthy controls with no history of opioid use (HC) [n=153]. Eighty-two variants in eight opioid system genes were studied. To establish the role of these genes in (a) non-dependent opioid use, and (b) heroin dependence, the following groups were compared: HC vs. NOD; HC vs. OD (MMT+HAT); and NOD vs. OD (MMT+HAT). ResultsFive unique SNPs in four genes showed nominally significant associations with non-dependent opioid use and heroin dependence. The association of the delta opioid receptor (OPRD1) intronic SNP rs2236861 with non-dependent opioid use (HC vs. NOD) remained significant after correction for multiple testing (OR=0.032; pcorrected=0.015). This SNP exhibited a significant gene–gene interaction with prepronociceptin (PNOC) SNP rs2722897 (OR=5.24; pcorrected=0.041) (HC vs. NOD). ConclusionsThis study identifies several new and some previously reported associations of variants with heroin dependence and with non-dependent opioid use, an important and difficult to obtain group not extensively studied previously. Further studies are warranted to confirm and elucidate the potential roles of these variants in the vulnerability to illicit drug use and drug addiction.

The paradox of decreasing nonmedical opioid analgesic use and increasing abuse or dependence — An assessment of demographic and substance use trends, United States, 2003–2014

BackgroundThe harms related to nonmedical use of opioid analgesics have impacted the United States for more than a decade. Examining trends in nonmedical use, abuse, and dependence among various demographic and substance using groups can provide critical insight for prevention and treatment activities. MethodsData from the National Survey on Drug Use and Health were used to assess trends in opioid analgesic nonmedical use, abuse, and dependence for 2003–2005, 2006–2008, 2009–2011, and 2012–2014. Multivariable logistic regression was used to identify characteristics associated with opioid analgesic abuse or dependence. ResultsRates of past-year opioid analgesic nonmedical use decreased from 48.4 per 1000 persons aged 12years and older in 2003–2005 to 43.3 in 2012–2014. Declines were seen among most demographic and substance using groups. In contrast, rates of past-year opioid analgesic abuse or dependence increased from 6.0 per 1000 persons in 2003–2005 to 7.5 in 2012–2014; increases were seen among most demographic and substance using groups. In 2012–2014, odds of opioid analgesic abuse or dependence were highest among those with sedative or tranquilizer and heroin abuse or dependence. ConclusionsThese findings indicate encouraging trends in overall nonmedical use of opioid analgesics which declined among many demographic and substance using groups. However, continued increases in rates of opioid analgesic abuse or dependence highlight the critical importance of maintaining efforts to drive down inappropriate opioid prescribing and expanding efforts to increase the provision of medication assisted treatment and psychosocial services for opioid use disorders and equipping individuals with naloxone to reverse opioid overdose.

Abnormal interhemispheric resting state functional connectivity of the insula in heroin users under methadone maintenance treatment

Abnormal interhemispheric functional connectivity is attracting more and more attention in the field of substance use. This study aimed to examine 1) the differences in interhemispheric functional connections of the insula with the contralateral insula and other brain regions between heroin users under methadone maintenance treatment (MMT) and healthy controls, and 2) the association between heroin users' interhemispheric insular functional connectivity using resting functional magnetic resonance imaging (fMRI) and the results of urine heroin analysis. Sixty male right-handed persons, including 30 with heroin dependence under MMT and 30 healthy controls, were recruited to this study. Resting fMRI experiments and urine heroin analysis were performed. Compared with the controls, the heroin users had a significantly lower interhemispheric insular functional connectivity. They also exhibited lower functional connectivity between insula and contralateral inferior orbital frontal lobe. After controlling for age, educational level and methadone dosage, less deviation of the interhemispheric insula functional connectivity was significantly associated with a lower risk of a positive urine heroin analysis result. Our findings demonstrated that the heroin users under MMT had abnormal long-range and interhemispheric resting functional connections. Those with a less dysfunctional interhemispheric insula functional connectivity had a lower risk of a positive urine heroin test.

Anxiety disorders are associated with early onset of heroin use and rapid transition to dependence in methadone maintained patients.

Early onset of heroin use is a severity marker of heroin use disorder. We studied the interaction between early onset and rapid transition to heroin dependence recorded with retrospective interviews in 213 patients with severe heroin dependence and history of methadone maintenance treatment. General linear models were used to identify independent factors associated with early onset, factors associated with rapid transition to dependence, and a multivariate model was used to study the interaction of those two dimensions. Lifetime history of anxiety disorders and age at onset of cannabis use are shared common risk factors and are associated with the interaction.

AUTS2 in the nucleus accumbens is essential for heroin-induced behavioral sensitization

Autism susceptibility candidate 2 (AUTS2) is a gene associated with autism and mental retardation. Recent studies have suggested an association of the AUTS2 gene with heroin dependence, and reduced AUTS2 gene expression may confer increased susceptibility to heroin dependence. However, the functional role of the AUTS2 protein in regulating enduring neuroadaptations in response to heroin exposure has not been established. Here, we investigated the effects of acute and chronic heroin exposure on AUTS2 mRNA and protein expression in the nucleus accumbens (NAc) and caudate-putamen (CPu) to determine whether changes in AUTS2 expression are associated with heroin-induced locomotor sensitization in mice. Moreover, we explored whether AUST2 knockdown affects heroin-induced locomotor sensitization. AUTS2 mRNA and protein expression in the NAc, but not the CPu, was decreased after chronic heroin (1mg/kg) administration. In the NAc, the expression of heroin-induced locomotor sensitization was enhanced through the lentiviral-AUTS2-shRNA-mediated knockdown of AUTS2, while the overexpression of AUTS2 attenuated the locomotor-stimulant effects of heroin. Together, these results indicate that AUTS2 in the NAc, but not the CPu, suppresses the initiation and expression of heroin-induced behavioral sensitization, suggesting that AUST2 may be a potential target for the treatment of heroin dependence.

Prevalence, correlates and patterns of heroin use among young adults in the United States

IntroductionThe prevalence of heroin use, abuse, and dependence has increased considerably over the past decade. This increase has largely been driven by young adults (18–25years). This study aims to improve the understanding of heroin use among young adults by determining the prevalence, correlates, patterns and attitude of heroin use among young adults in the US. MethodsThe 2011–2013 National Survey on Drug Use and Health was analyzed. Study population included 55,940 young adults with valid interviews. Self-reported lifetime, past-year and past-month use of heroin were examined. Descriptive statistics and adjusted odds ratios were estimated in accordance with the complex survey design. ResultsOf the respondents, 18.4 per 1000 (95% CI=16.8–20.0) used heroin at some time in their lives, and 7.3 per 1000 (95% CI=6.3–8.3) and 3.3 per 1000 (95% CI=2.6–4.0) used heroin in the past year and past month, respectively. The single most common route of heroin use was by sniffing. Majority of young adults reported using heroin in combination with other substances. Users of non-prescribed opioid pain relievers, cigarette smokers, illicit drug users and those arrested and booked for breaking the law, had higher odds of using heroin during their lifetime, in the past-year and past-month. ConclusionFewer than 2% reported ever using heroin, and 82% of those reported no use in the past month. Majority were polysubstance users and sniffed heroin in combination with other routes of use. Comprehensive programs that target young adult heroin users and address important risk factors for heroin use are needed.

Genome-wide Association Study of Cannabis Dependence Severity, Novel Risk Variants, and Shared Genetic Risks

Cannabis dependence (CAD) is a serious problem worldwide and is of growing importance in the United States because cannabis is increasingly available legally. Although genetic factors contribute substantially to CAD risk, at present no well-established specific genetic risk factors for CAD have been elucidated. To report findings for DSM-IV CAD criteria from association analyses performed in large cohorts of African American and European American participants from 3 studies of substance use disorder genetics. This genome-wide association study for DSM-IV CAD criterion count was performed in 3 independent substance dependence cohorts (the Yale-Penn Study, Study of Addiction: Genetics and Environment [SAGE], and International Consortium on the Genetics of Heroin Dependence [ICGHD]). A referral sample and volunteers recruited in the community and from substance abuse treatment centers included 6000 African American and 8754 European American participants, including some from small families. Participants from the Yale-Penn Study were recruited from 2000 to 2013. Data were collected for the SAGE trial from 1990 to 2007 and for the ICGHD from 2004 to 2009. Data were analyzed from January 2, 2013, to November 9, 2015. Criterion count for DSM-IV CAD. Among the 14 754 participants, 7879 were male, 6875 were female, and the mean (SD) age was 39.2 (10.2) years. Three independent regions with genome-wide significant single-nucleotide polymorphism associations were identified, considering the largest possible sample. These included rs143244591 (β = 0.54, P = 4.32 × 10-10 for the meta-analysis) in novel antisense transcript RP11-206M11.7;rs146091982 (β = 0.54, P = 1.33 × 10-9 for the meta-analysis) in the solute carrier family 35 member G1 gene (SLC35G1); and rs77378271 (β = 0.29, P = 2.13 × 10-8 for the meta-analysis) in the CUB and Sushi multiple domains 1 gene (CSMD1). Also noted was evidence of genome-level pleiotropy between CAD and major depressive disorder and for an association with single-nucleotide polymorphisms in genes associated with schizophrenia risk. Several of the genes identified have functions related to neuronal calcium homeostasis or central nervous system development. These results are the first, to our knowledge, to identify specific CAD risk alleles and potential genetic factors contributing to the comorbidity of CAD with major depression and schizophrenia.

Reentry programming for opioid and opiate involved female offenders: Findings from a mixed methods evaluation

PurposeThis study examined the effectiveness of Second Chance Act Grant funded reentry program for dually diagnosed female offenders involved in opioid and opiate use. MethodsA mixed methods design utilizing qualitative interviews and a quasi-experimental design was used to both determine program effectiveness and explore women's narratives regarding their addiction and incarceration. ResultsFindings from a quasi-experimental design indicate that program participation significantly reduced recidivism as did marital status. Qualitative interview findings suggest that the licit use of prescription opioid medication preceded heroin dependency in many cases which resulted in related criminality. Focus group interviews also indicated that participants responded positively to programming but had variable levels of self-efficacy. ConclusionsReentry programs designed for male offenders can also reduce recidivism among female offenders. America's burgeoning heroin epidemic has the potential for significant costs for local criminal justice systems as more lower level drug offenders are sentenced to jails instead of state prisons.

Psychopathology of addiction: May a SCL-90-based five dimensions structure be applied irrespectively of the involved drug?

BackgroundWe previously found a five cluster of psychological symptoms in heroin use disorder (HUD) patients: ‘worthlessness-being trapped’, ‘somatic-symptoms’, ‘sensitivity-psychoticism’, ‘panic-anxiety’, and ‘violence-suicide’. We demonstrated that this aggregation is independent of the chosen treatment, of intoxication status and of the presence of psychiatric problems.Methods2314 Subjects, with alcohol, heroin or cocaine dependence were assigned to one of the five clusters. Differences between patients dependent on alcohol, heroin and cocaine in the frequency of the five clusters and in their severity were analysed. The association between the secondary abuse of alcohol and cocaine and the five clusters was also considered in the subsample of HUD patients.ResultsWe confirmed a positive association of the ‘somatic symptoms’ dimension with the condition of heroin versus cocaine dependence and of the ‘sensitivity-psychoticism’ dimension with the condition of alcohol versus heroin dependence. ‘Somatic symptoms’ and ‘panic anxiety’ successfully discriminated between patients as being alcohol, heroin or cocaine dependents. Looking at the subsample of heroin dependents, no significant differences were observed.ConclusionsThe available evidence coming from our results, taken as a whole, seems to support the extension of the psychopathological structure previously observed in opioid addicts to the population of alcohol and cocaine dependents.

Amphetamine Replacement for Cocaine Dependence

Ongoing cocaine dependence can compromise heroin-assisted treatment for patients with methadone-refractory heroin dependence. In a multicenter trial

Effective drug therapy for cocaine dependence: a milestone.

In The Lancet, Mascha Nuijten and colleagues 1 Nuijten M Blanken P van de Wetering B Nuijen B van den Brink W Hendriks VM Sustained-release dexamfetamine in the treatment of chronic cocaine-dependent patients on heroin-assisted treatment: a randomised, double-blind, placebo-controlled trial. Lancet. 2016; (published online March 22.)http://dx.doi.org/10.1016/S0140-6736(16)00205-1 Google Scholar present the results of a multicentre, randomised, double-blind, placebo-controlled trial assessing the acceptance, safety, and efficacy of sustained-release dexamfetamine in cocaine-dependent patients on heroin-assisted treatment. The study findings showed that 60 mg/day oral sustained-release dexamfetamine over 12 weeks was well accepted, safe, and superior to placebo in terms of days of cocaine use (mean 44·9 days [SD 29·4] in the sustained-release dexamfetamine group vs 60·6 days [24·3] in the placebo group [95% CI of difference 3·1–28·4]; p=0·031; Cohen's standardised effect size d=0·58) and all self-reported and urine-based cocaine use-related outcomes. Cocaine dependence is prevalent throughout the world and causes major morbidity and mortality. 2 Degenhardt L Hall W Extent of illicit drug use and dependence, and their contribution to the global burden of disease. Lancet. 2012; 379: 55-70 Summary Full Text Full Text PDF PubMed Scopus (868) Google Scholar At present, no effective pharmacotherapy exists. Agonist replacement therapy has been successfully applied to opioid and tobacco dependence, 3 Strain EC Bigelow GE Liebson IA Stitzer ML Moderate- vs high-dose methadone in the treatment of opioid dependence: a randomized trial. JAMA. 1999; 281: 1000-1005 Crossref PubMed Scopus (359) Google Scholar , 4 Aubin HJ Luquiens A Berlin I Pharmacotherapy for smoking cessation: pharmacological principles and clinical practice. Br J Clin Pharmacol. 2014; 77: 324-336 Crossref PubMed Scopus (73) Google Scholar but previous studies examining this approach in cocaine dependence failed to find statistically significant benefits in terms of reduced cocaine use, or showed indecisive results. This could be due to limitations in the methods, such as small sample sizes, 5 Shearer J Wodak A van Beek I Mattick RP Lewis J Pilot randomized double blind placebo-controlled study of dexamphetamine for cocaine dependence. Addiction. 2003; 98: 1137-1141 Crossref PubMed Scopus (120) Google Scholar inadequate dosing schemes, 6 Dursteler KM Berger EM Strasser J et al. Clinical potential of methylphenidate in the treatment of cocaine addiction: a review of the current evidence. Subst Abuse Rehabil. 2015; 6: 61-74 Crossref PubMed Google Scholar or large attrition rates. 7 Grabowski J Rhoades H Stotts A et al. Agonist-like or antagonist-like treatment for cocaine dependence with methadone for heroin dependence: two double-blind randomized clinical trials. Neuropsychopharmacology. 2004; 29: 969-981 Crossref PubMed Scopus (168) Google Scholar The study by Nuijten and colleagues 1 Nuijten M Blanken P van de Wetering B Nuijen B van den Brink W Hendriks VM Sustained-release dexamfetamine in the treatment of chronic cocaine-dependent patients on heroin-assisted treatment: a randomised, double-blind, placebo-controlled trial. Lancet. 2016; (published online March 22.)http://dx.doi.org/10.1016/S0140-6736(16)00205-1 Google Scholar overcomes most of these shortcomings. Sustained-release dexamfetamine in the treatment of chronic cocaine-dependent patients on heroin-assisted treatment: a randomised, double-blind, placebo-controlled trialSustained-release dexamfetamine is a well accepted, effective, and safe agonist pharmacotherapy for comorbid treatment-refractory cocaine dependence in heroin-dependent patients in heroin-assisted treatment. Future research should aim to replicate these findings in chronic cocaine-dependent and other stimulant-dependent patients in more routine treatment settings, including strategies to optimise treatment adherence like medication management interventions and contingency management. Full-Text PDF

Psychosis in a blindness patient: A case report

IntroductionUsing a clinical case as illustration, the present work engages the different psychopathologic alterations that blindness patients could present.MethodsThe presentation and discussion of a clinical case of psychosis in a blind patient are addressed. The scientific documentation used as support was obtained from PubMed/Medline search engines using as keywords blindness and psychosis.ResultsA 43-years-old male patient, with a medical history of arterial hypertension, heroine dependence (presently with methadone schema) and bilateral blindness caused by a bilateral retinal detachment 20 years ago, was admitted in the psychiatric ward. The patient's historical record includes a previous personality with paranoid characteristics, as well as a hospitalization due to persecutory and auto-reference ideas and kinaesthetic hallucinations with 1 month of evolution, coincident with address changes. Lab tests revealed the following results: haemoglobin 13.8; Leucocytosis 13,400; CRP: 6.2; ALT &gt; AST. Positive results were obtained in the drug tests for cannabinoids, as well as for the anti-HCV antibody (IgG). Finally, the patient was medicated with an antipsychotic and humour stabilizer, achieving a significant improvement after 10 days of hospitalization.ConclusionsAlthough studies reveal that mental and behavioural disorders, especially those with symptoms of psychosis and mental retardation, are common among people with congenital blindness, more knowledge of the prevalence and aetiology of mental and behavioural disorders among people suffering from blindness is needed.Disclosure of interestThe authors have not supplied their declaration of competing interest.

Treatment of heroin dependence with ibogaine

BackgroundThe use of the hallucinogen ibogaine as an anti-addiction agent has been described in several case reports, dating back to the eighties. The anti-addiction properties of ibogaine have been confirmed in a large body of animal work. Ibogaine has been shown to be effective in reducing withdrawal severity and substance use for a variety of substances, including cocaine and opiates. Animal studies also show some potentially dangerous adverse reactions, including cerebellar toxicity and potential cardiac effects. While pharmacological treatment options for opiate and cocaine dependence are still limited, ibogaine assisted treatment might be a promising new option. Therefore more systematic studies on its toxicity and efficacy are warranted. In our studies we address these two research questions: is ibogaine treatment for opiate dependence safe and effective for treating opiate withdrawal and relapse prevention? A secondary objective is to explore the pharmacokinetic properties of ibogaine.MethodsAnimal work: first we performed a systematic review and meta-analysis of animal studies on ibogaine. Thirty studies were included in the systematic review, of which 27 could be analyzed in meta-analysis. Human studies: fifteen opiate dependent patients will be treated with ibogaine (10 mg/kg), on top of treatment as usual. Ibogaine toxicity will be assessed through close monitoring with electrocardiography, with QTc prolongation as main outcome measure, repeated assessments of ataxia using the (SARA) and observation of psychotic symptoms by using the Delirium Observations Scale (DOS). Ibogaine efficacy will be measured, using repeated evaluations of opiate withdrawal severity (Subjective Opiate Withdrawal Scale: SOWS; Objective Opiate Withdrawal Scale: OOWS), craving intensity (using a Visual Analogue Scale) and substance use, with a six-month follow-up. Clinical observations in ibogaine treated individuals will be compared with a cohort of opiate dependent patients treated with a rapid detoxification procedure. Both acute and long-term effects will be linked with serum ibogaine and noribogaine levels.ResultsAnimal work: overall, ibogaine reduced drug self-administration, particularly during the first 24 hours after administration. Ibogaine had no effect on drug-induced conditioned place preference. Ibogaine administration resulted in motor impairment in the first 24 hours after supplementation, and cerebral cell loss even weeks after administration. Data on ibogaines effect on cardiac rhythm as well as on its neuropharmacological working mechanisms are limited. Human studies: human data are still being collected. Treatment of the first patients confirmed strong effects of ibogaine on heart rhythm (QTc prolongation) and ataxia, while the opiate withdrawal symptoms were relatively mild. The first observations on the clinical effect of ibogaine on craving and substance use will also be shared.ConclusionsBased on our meta-analysis of animal data, there is strong evidence that ibogaine is effective in reducing drug self-administration in animals. This warrants further studies into the clinical efficacy of ibogaine in substance dependent patients in reducing craving and substance use. Our first clinical experiences in a limited number of patients confirm that ibogaine treatment may be effective in reducing opiate withdrawal, but can potentially have transient cardiac and cerebellar toxicity.Disclosure of interestThe authors have not supplied his declaration of competing interest.

Psychic Structure of Opioid Addiction

Background: By applying a Principal Component Analysis (PCA) to the items of the SCL-90 checklist, we previously investigated the psychopathologic structure of individuals with heroin addiction, finding a 5-factor aggregation of psychological/psychiatric symptoms: “Worthlessness and Being trapped,” “Somatic Symptoms,” “Sensitivity-Psychoticism,” “Panic-Anxiety,” and “Violence-Suicide.” Our studies on this subject did not, however, explore the possible impact of comorbid psychiatric conditions on 5 psychopathologic dimensions listed above. The aim of the present study is to verify whether there is any difference in these 5 dimensions between heroin-addicted patients with (PC-HA) or without (NPC-HA) known lifetime psychiatric problems. Methods: A total of 1195 patients with heroin dependence entering a residential therapeutic community treatment were assigned to one of the 5-factor solutions yielded by Principal Component Analysis on the basis of the highest z score obtained. Differences between NPC-HA and PC-HA patients in the frequency of the 5 psychopathologic dimensions and in their severity were then analyzed by means of univariate and multivariate analyses. Results: All the SCL-90 factor scores were, from a statistical viewpoint, significantly higher in PC-HA than in NPC-HA patients, but the only statistically significant differences in the frequency of the 5 psychopathological dimensions were those observed in the case of “Panic-Anxiety,” which turned out to be higher in the PC-HA group. Stepwise discriminant analysis showed that the severity of “Somatic Symptoms” and “Panic-Anxiety” made these 2 factors the only ones that successfully discriminated between NPC-HA and PC-HA patients. The other SCL-90-based psychopathologic dimensions were unable to improve the value of the discrimination. Conclusions: On the basis of our results, the SCL-90-defined structure of opioid addiction may be considered to be only partly dependent on the presence of a “psychiatric” condition. This observation adds to the previous ones that go to show the stability of the above aggregations of symptoms, irrespectively of other demographic and clinical characteristics, as well as active involvement with heroin abuse or the kind of treatment chosen. When the available evidence is considered as a whole, it seems to support the trait-dependent, rather than state-dependent, nature of the proposed factorial dimensions of the psychopathology of opioid addiction.

Machine-learning identifies substance-specific behavioral markers for opiate and stimulant dependence

BackgroundRecent animal and human studies reveal distinct cognitive and neurobiological differences between opiate and stimulant addictions; however, our understanding of the common and specific effects of these two classes of drugs remains limited due to the high rates of polysubstance-dependence among drug users. MethodsThe goal of the current study was to identify multivariate substance-specific markers classifying heroin dependence (HD) and amphetamine dependence (AD), by using machine-learning approaches. Participants included 39 amphetamine mono-dependent, 44 heroin mono-dependent, 58 polysubstance dependent, and 81 non-substance dependent individuals. The majority of substance dependent participants were in protracted abstinence. We used demographic, personality (trait impulsivity, trait psychopathy, aggression, sensation seeking), psychiatric (attention deficit hyperactivity disorder, conduct disorder, antisocial personality disorder, psychopathy, anxiety, depression), and neurocognitive impulsivity measures (Delay Discounting, Go/No-Go, Stop Signal, Immediate Memory, Balloon Analogue Risk, Cambridge Gambling, and Iowa Gambling tasks) as predictors in a machine-learning algorithm. ResultsThe machine-learning approach revealed substance-specific multivariate profiles that classified HD and AD in new samples with high degree of accuracy. Out of 54 predictors, psychopathy was the only classifier common to both types of addiction. Important dissociations emerged between factors classifying HD and AD, which often showed opposite patterns among individuals with HD and AD. ConclusionsThese results suggest that different mechanisms may underlie HD and AD, challenging the unitary account of drug addiction. This line of work may shed light on the development of standardized and cost-efficient clinical diagnostic tests and facilitate the development of individualized prevention and intervention programs for HD and AD.

Characteristics of heroin-dependent patients seeking asthma care in the ED

BackgroundLimited data suggest that heroin worsens asthma severity, but little is known about heroin-dependent patients who seek emergency department (ED) care for asthma. ObjectivesTo describe what heroin-dependent patients know about their asthma and how they use health care resources. MethodsA prospective study of heroin-dependent patients seeking care for “asthma” at an urban ED with 130000 annual visits was conducted. Eligible subjects were English-speaking heroin-dependent adults seeking care for mild to moderate asthma symptoms. A closed-format survey instrument to assess opioid use, asthma knowledge, and health care use was developed by content experts, piloted for study performance, revised, and then administered to eligible patients prior to ED discharge. Descriptive analysis was done. ResultsThirty subjects participated. Mean age was 47.5years; 21 (70%) were male. Most used heroin several times weekly. Intranasal was the most common route (93%). Almost half (47%) stated that their asthma was diagnosed in the ED, 13% by a primary care physician, 13% by a lung specialist, and 27% did not know how diagnosed. The ED was used as the primary source for asthma medications in 73% cases; 43% used the ED for breathing issues at least once per month. Most subjects (77%) felt that heroin worsened their asthma symptoms. Only 7 (23%) also abused prescription opioids, and only 7 (23%) knew about prescription naloxone. ConclusionPatients with heroin dependence frequently use the ED for their health care needs related to asthma. Most do not have other health care providers, most have limited health literacy, and all would benefit from referral to a primary care provider and substance abuse resources.

Neurocognitive and psychiatric dimensions of hot, but not cool, impulsivity predict HIV sexual risk behaviors among drug users in protracted abstinence

ABSTRACTBackground: Impulsivity is an important risk factor for HIV risky drug and sexual behaviors. Research identifies hot (i.e. affectively-mediated, reward-based) and cool (motoric, attentional, independent of context) neurocognitive and psychiatric dimensions of impulsivity, though the impact of specific drugs of abuse on these varieties of impulsivity remains an open question. Objectives: The present study examined the associations of neurocognitive and psychiatric varieties of hot and cool impulsivity with measures of lifetime and recent sexual risk behaviors among users of different classes of drugs. Methods: The study sample was comprised of drug users in protracted (> 1 year) abstinence: heroin mono-dependent (n = 61), amphetamine mono-dependent (n = 44), and polysubstance dependent (n = 73). Hot impulsivity was operationalized via neurocognitive tasks of reward-based decision-making and symptoms of psychopathy. Cool impulsivity was operationalized via neurocognitive tasks of response inhibition and symptoms of attention deficit/hyperactivity disorder (ADHD). Results: Hot impulsivity was associated with sexual risk behaviors among heroin and amphetamine users in protracted abstinence, whereas cool impulsivity was not associated with sexual risk behaviors among any drug-using group. Neurocognitive hot impulsivity was associated with recent (past 30-day) sexual risk behaviors, whereas psychopathy was associated with sexual risk behaviors during more remote time-periods (past 6 month and lifetime) and mediated the association between heroin dependence and past 6-month sexual risk behaviors. Conclusion: Assessments and interventions aimed at reducing sexual risk behaviors among drug users should focus on hot neurocognitive and psychiatric dimensions of impulsivity, such as decision-making and psychopathy. Cool dimensions of impulsivity such as response inhibition and ADHD were not related to sexual risk behaviors among drug users in protracted abstinence.