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This study investigated the architecture and neural activity of white matter functional networks (WMFNs) in individuals with opioid use disorder (OUD) after prolonged abstinence, compared with healthy controls (HCs).
Methods
Blood oxygen level-dependent signals in white matter were analyzed using a data-driven k-means clustering approach across individuals with OUD at baseline (OUD1), the same individuals after prolonged abstinence at follow-up (OUD2), and HCs.
Results
In OUD1, the deep frontoparietal network was fragmented into the superior longitudinal fasciculus network and anterior corona radiata network; this organization partially recovered in OUD2, becoming more similar to HCs. OUD1 also showed hyperactivation in the deep frontal network and hypoactivation in the frontotemporal-parietal network, with frontotemporal-parietal activity negatively correlated with years of opioid use.
Conclusions
OUD is associated with disrupted architecture of WMFNs and altered neural activity, whereas prolonged abstinence may promote partial network restoration. These findings highlight the neuroplastic potential of WMFNs during recovery and provide insights into the neural mechanisms underlying OUD and abstinence-related rehabilitation.
Estimating the prevalence of use of substances such as heroin remains a challenge. The aim of this study is to identify the scientific publications in Spain that have used surveys to investigate heroin use, to describe their methodology and to contrast the formulation of the questions with users’ input on key aspects associated with use.
Methods:
A scoping review was conducted until November 2024 in MEDLINE (Ovid), EMBASE and Web of Science. The review included questionnaire-based research studies assessing heroin use in Spain. Information on study, population, data collection and consumption characteristics was compiled from each included study. In addition, in-depth interviews were conducted with Spanish heroin current users and ex-users.
Results:
Twenty-nine questionnaire-based research studies assessing heroin use in Spain were identified; none of them were specifically oriented to estimate and characterise heroin use at the population level. Most of the studies focused on specific population groups, mainly drug users, students, or inmates. The majority addressed lifetime, past-year, and past-month use, although users found the past 3 or 6 months more relevant. Few studies explored other use characteristics; however, interviews with heroin ex-users highlighted the importance of factors like route of administration and age of first use.
Conclusions:
The studies identified in this review vary in terms of target population, geographic scope, reference time frame, and data collection methods. Moreover, questionnaires rarely address additional characteristics of use that are considered relevant by former users. This review identifies areas for improvement to guide future studies and refine methodological approaches.
Opioid use disorder (OUD) is a major global-scale social issue affecting public health. The high potential for addiction and dependence makes opioid use a significant concern, contributing to substance-related disorders. Both genetic and environmental factors contribute to the predisposition to OUD, with the opioidergic, dopaminergic, and GABAergic systems playing primary roles in itsonset.
Methods
This narrative review documents the association between genes and their variants related to these three systems, along with current evidence on epigenetic interventions in OUD. Relevant studies investigating candidate-gene associations and molecular mechanisms were synthesized to highlight genetic variants and epigenetic processes linked to OUD.
Results
Genetic associations play a prominent role in OUD, with several single-nucleotide variants identified in affected populations. Key genes implicated include OPRM1, OPRD1, OPRK1, PDYN, OPRL1, and POMC from the opioidergic system; DRD1, DRD2, DRD3, DRD4, ANKK1, and COMT from the dopaminergic system; and GABRA2, GABRB3, GABRG2, GAD1, and GAD2 from the GABAergic system. Evidence also indicates that chronic opioid use is associated with epigenetic changes through posttranslational histone modifications and DNA methylation. However, limitations in existing studies include small sample sizes, limited replication, and potential stratification biases.
Conclusions
Although many candidate-gene associations have been proposed for OUD, robust evidence remains limited. Large, ancestrally diverse genome-wide association studies (GWAS) and systematic replication studies are urgently needed. A deeper understanding of the genetic, epigenetic, and neurobiological bases of addiction will be essential for the development of precisely targeted medications to improve prevention and treatment outcomes for OUD.
Methadone maintenance treatment (MMT) and protracted abstinence (PA) effectively reduce the craving for heroin among individuals with heroin use disorder (HUD). However, the difference in their effects on brain function, especially the coupling among the large-scale brain networks (default mode [DMN], salience [SN], and executive control [ECN] networks), remains unclear. This study analyzed the effects of the MMT and PA on these networks and the predictive value of the bilateral resource allocation index (RAI) for craving for heroin.
Methods
Twenty-five individuals undergoing the MMT, 22 undergoing the PA, and 51 healthy controls underwent resting-state functional magnetic resonance imaging (rs-fMRI). Independent component analysis identified the ECN, DMN, and SN. The SN-ECN and SN-DMN connectivity and the bilateral RAI were evaluated. The relationships between network coupling and clinical and psychological characteristics were analyzed. The multiple linear regression model identified significant variables for predicting craving scores.
Results
The MMT group showed significantly stronger SN-left ECN (lECN) coupling and left RAI than the PA group. In the MMT group, SN-lECN connectivity and bilateral RAI were positively correlated with the total methadone dose. In both treatment groups, SN-right ECN (rECN) connectivity and right RAI were negatively correlated with craving. The models revealed that the bilateral RAI and the MMT and PA were associated with the craving.
Conclusions
The MMT enhances SN-lECN coupling and the left RAI more than the PA, possibly due to higher control modulation. The RAI could help predict heroin craving in individuals with HUD undergoing either treatment program.
Stimulants like cocaine, amphetamines, and ecstasy produce short-term desirable effects like alertness, euphoria, and energy. However, they can also cause short- and long-term harm, leading to addiction, dependence, and withdrawal syndrome. Sedative drugs like cannabis, opioids, and benzodiazepines create feelings of calmness and relaxation but can be dangerous in overdose, particularly if mixed with other sedatives. Repeated use of sedatives can lead to severe dependence. Cannabis is the most commonly used illegal drug and can cause paranoia, psychosis, memory problems, and mood disorders with long-term heavy use. Synthetic cannabinoids like ‘spice’ are stronger and more harmful than natural cannabis. Hallucinogens like LSD cause distortions, hallucinations, confusion, and disorientation. They don’t cause dependence but can damage the brain with repeated use. Dissociative drugs like nitrous oxide and ketamine cause disorientation, perceptual disturbances, and loss of physical coordination, leading to accidental injury. Long-term use of ketamine can damage the bladder, and nitrous oxide can cause memory problems and severe nerve damage.
Edited by
Rachel Thomasson, Manchester Centre for Clinical Neurosciences,Elspeth Guthrie, Leeds Institute of Health Sciences,Allan House, Leeds Institute of Health Sciences
substances other than alcohol (see Chapter 8). The purpose is to introduce the reader to the wide variety of substances that are abused by explaining why people may use them, why the use can be harmful and broadly how this is managed. Liaison psychiatry is the bridge between inpatient care and community care and this complex relationship is demonstrated herein when discussing the management of these cases that require the input of a variety of clinicians. The substances detailed are further subdivided to cover background information, acute intoxication, toxicity, withdrawal states and other management advice. ‘Top tips’ are included where appropriate, which are practical considerations to make based on day-to-day experience working in the field.
The amount of people worldwide who regularly used opioids in 2021 is staggering, and if something is not done to change the course of this epidemic, the numbers will continue to increase year over year, just as they have done over the last decade. Roughly 275 million people globally report having used drugs of any kind in the past year, an increase of almost 50 million people over the past ten years. While some of this increase was due to the 10% rise in global population over the same period, this alone cannot account for the entirety of the 22% rise in global drug use. Health-care systems around the world are being stretched beyond their capabilities to manage a population this large, and the number of people with opioid use disorder is projected to continue to increase in size over the next decade. The effects of the opioid epidemic on healthcare systems are particularly devastating in poorer and middle-income countries with less robust resources. Over the past decade the number of individuals with opioid use disorder has increased by almost 9 million, an increase of over 33%, and now affects 0.7% of the current global population.
Consuming opioids for nonmedical reasons has occurred for centuries. Although epidemiologic research on opioid misuse can be difficult, we do know that it differs from what has been witnessed in the past. The types of opioids, the methods in which they are consumed and the geographical locations most affected are just some of the characteristics that have changed over time. Efforts are currently underway to predict the course of the opioid epidemic through the use of mathematical modeling and computer programming.
Opium, manufactured from the sap of the opium poppy (Papaver somniferum), has been cultivated by humans for centuries. It has been used, in one form or another, for medicinal as well as recreational purposes, and is the precursor to all modern-day opiate pharmaceutical agents. Morphine, the active ingredient in opium, was isolated from opium in 1803, and very quickly became widely used as strong painkiller. As a result of its effectiveness and widespread use many people began to become addicted to the medication. In an attempt to create a safer and less addictive alternative to morphine, heroin was synthesized from morphine in 1874 and marketed by pharmaceutical company Bayer as a morphine substitute, and so the modern world’s struggle with opioid misuse continued. Over a century ago the world recognized that opioid addiction was a significant problem that needed to be addressed, and yet today we are faced with an escalating epidemic of opioid misuse and addiction, a world in which few, if any of us, have remained unscathed. This chapter focuses on the specific factors which have led to the exponential increase in opioid misuse throughout the world over the last century
Harm reduction refers to a set of strategies aimed to limit the negative consequences associated with drug use, but without requiring complete abstinence. Some harm-reduction strategies aim to reduce the risk of overdose, such as the use of naloxone rescue kits, fentanyl testing strips, and implementation of Good Samaritan laws. Other strategies lower the risk of overdose but also the likelihood of contracting infectious diseases such as HIV and hepatitis. Syringe services programs, also referred to as needle exchange programs, and supervised consumption facilities all fall under this category. Medications for opioid use disorder (MOUD), which include methadone, buprenorphine, and naltrexone, have been proven to lower the risk of overdose, improve the likelihood of maintaining sobriety, and therefore lower rates of disease transmission. Finally, harm reduction is utilized in criminal justice system through the use of drug decriminalization, police diversion programs, and drug treatment courts.
Opioid misuse is now a worldwide epidemic and major public health issue with widespread implications. This fascinating book provides a collection of compelling arguments on how the course of the opioid epidemic can be changed. It offers an overview of the historical origins of opioid addiction, a summary of the current state of the worldwide epidemic and an examination of the likelihood of success for current and proposed solutions. Specific chapters focus on why some people are affected by addiction, the effect of policy and regulations, changing trends in opioid use, detoxification, the financial cost of addiction treatment, and proactive measures to prevent addiction. Drawing upon both past and current academic research as well as personal accounts, ideas and concepts are presented in a clear and accessible narrative. This book is a convenient single source of information for healthcare professionals, students and individuals personally affected by opioid addiction.
Many studies aggregate prescription opioid misuse (POM) and heroin use into a single phenotype, but emerging evidence suggests that their genetic and environmental influences may be partially distinct.
Methods
In total, 7164 individual twins (84.12% complete pairs; 59.81% female; mean age = 30.58 years) from the Australian Twin Registry reported their lifetime misuse of prescription opioids, stimulants, and sedatives, and lifetime use of heroin, cannabis, cocaine/crack, illicit stimulants, hallucinogens, inhalants, solvents, and dissociatives via telephone interview. Independent pathway models (IPMs) and common pathway models (CPMs) partitioned the variance of drug use phenotypes into general and drug-specific genetic (a), common environmental (c), and unique environmental factors (e).
Results
An IPM with one general a and one general e factor and a one-factor CPM provided comparable fit to the data. General factors accounted for 55% (a = 14%, e = 41%) and 79% (a = 64%, e = 15%) of the respective variation in POM and heroin use in the IPM, and 25% (a = 12%, c = 8%, e = 5%) and 80% (a = 38%, c = 27%, e = 15%) of the respective variation in POM and heroin use in the CPM. Across both models, POM emerged with substantial drug-specific genetic influence (26–39% of total phenotypic variance; 69–74% of genetic variance); heroin use did not (0% of total phenotypic variance; 0% of genetic variance in both models). Prescription sedative misuse also demonstrated significant drug-specific genetic variance.
Conclusions
Genetic variation in POM, but not heroin use, is predominantly drug-specific. Misuse of prescription medications that reduce experiences of subjective distress may be partially influenced by sources of genetic variation separate from illicit drug use.
This chapter presents the book’s second case study: Chinese efforts to manage ‘non-traditional’ security issues in the Greater Mekong Subregion. It focuses on the challenges of illegal narcotics and associated criminal activity, particularly banditry on the Mekong river, to which China has become more exposed through its ‘reform and opening up’. Contrary to widespread assumptions that ‘Westphalian’ China is leery of undermining sovereignty, we show that Chinese agencies have actually moved to tackle these problems at source by sponsoring opium-substitution programmes and transboundary law-enforcement projects in Laos and Myanmar. The outcomes of these interventions depend on how Chinese party-state transformation dynamics interact with socio-political conflicts in these target states. On the Chinese side, opium-substitution has been hijacked by local cadre-capitalists in Yunnan province, skewing implementation towards their sectional interests. This has intersected with predatory social relations in Myanmar and Laos to undermine drug-suppression efforts. Conversely, Chinese central government agencies have had greater success in corralling neighbouring counterparts into a transnational policing network, recently cemented into a new international organisation, the Lancang-Mekong Law Enforcement and Security Centre.
Based on hubs of neural circuits associated with addiction and their degree centrality (DC), this study aimed to construct the addiction-related brain networks for patients diagnosed with heroin dependence undertaking stable methadone maintenance treatment (MMT) and further prospectively identify the ones at high risk for relapse with cluster analysis.
Methods
Sixty-two male MMT patients and 30 matched healthy controls (HC) underwent brain resting-state functional MRI data acquisition. The patients received 26-month follow-up for the monthly illegal-drug-use information. Ten addiction-related hubs were chosen to construct a user-defined network for the patients. Then the networks were discriminated with K-means-clustering-algorithm into different groups and followed by comparative analysis to the groups and HC. Regression analysis was used to investigate the brain regions significantly contributed to relapse.
Results
Sixty MMT patients were classified into two groups according to their brain-network patterns calculated by the best clustering-number-K. The two groups had no difference in the demographic, psychological indicators and clinical information except relapse rate and total heroin consumption. The group with high-relapse had a wider range of DC changes in the cortical−striatal−thalamic circuit relative to HC and a reduced DC in the mesocorticolimbic circuit relative to the low-relapse group. DC activity in NAc, vACC, hippocampus and amygdala were closely related with relapse.
Conclusion
MMT patients can be identified and classified into two subgroups with significantly different relapse rates by defining distinct brain-network patterns even if we are blind to their relapse outcomes in advance. This may provide a new strategy to optimize MMT.
In this paper, I reflect on two of my intertwined research interests. The first is my professional engagement with researching drug use and abuse in Ireland, especially heroin addiction, in applied ethnographic projects, generally answering a specific set of questions on how services for ‘drug addiction’ work. My second interest is the historical construction of ‘addiction’ and the discursive intersections that produce various kinds of power, subjects, and techniques around this concept. I find the dialectical relationship between heroin and methadone in Ireland, especially the emergence of heroin ‘injecting rooms’, as a window into how drugs are social things. Drugs and the bodies who take them live in complex moral worlds, not as inert objects surrounded by abstract human creations. These worlds are an integral part of how ‘addiction’ works and how drugs treating addiction are actually used. Without a deeper understanding of such complexities we will continue to miss key issues in the lives of people we hope to help.
Substance use and misuse remain a feature of everyday life in the UK today. It is a cause of death and disability and a marker of deprivation and inequality. The health, social and criminal justice systems currently in place are not able to provide the flexible response in which the public can have confidence and to which they can adhere. While much of the debate has centred on younger people, including children and adolescents, attention has recently turned to older people who are misusing cannabis and heroin as well as over-the-counter and medically prescribed medications. The remarkable contributions of neuroscience over the half-century of 1960–2010 have demonstrated the biological basis of substance misuse, which can become a chronic medical condition, much like diabetes and hypertension. There is exciting potential for the development of new pharmaceutical agents for the treatment of substance misuse. An aspiration we have is towards a new public understanding of addiction through education so that people can make informed choices based on realistic policies.
The term ‘amaphara’, possibly derived from ‘parasites’, burst into South African public culture in the 2010s to refer to petty thieves addicted to a heroin-based drug locally called whoonga/nyaope. Drawing on ethnography and media sources to interrogate the rise of ‘amaphara’, this paper argues that South Africa's heroin epidemic magnifies the attention – criticism but also sympathy – directed toward marginalised black men who have few prospects for social mobility. It locates amaphara in the national context where drug policy is largely punitive and youth unemployment rates are painfully high, but gives particular attention to families’ and communities’ experiences with intimate crimes, especially petty thefts. It further shows that amaphara is a contested term: heroin users are brothers, sons and grandchildren and they gain most of their income not from crime but by undertaking useful piece work in communities.
This study was carried out on 149 of Heroin dependent patient that admission for detoxification.
Design:
This study is a 10 days double blind placebo-controlled trial.
Place & duration of study:
This study is a 10 days double blind placebo-controlled trial which was carried out on 149 of Heroin dependent patient that admission for detoxification in Mashhad Ebne-sina hospital in 1385-1386 Subjects were randomly divided into topiramate and placebo detoxification groups.
Subjects & methods:
Topiramate group receive topiramate (max 200 mg) for 10 days. The placebo group received usual regimen and placebo. Withdrawal symptoms were assessed by Subjective and Objective Opiate Withdrawal Scale in days 1, 3, 5, 7, 10.information s analyzed by chi-square test for qualities variables and T-test & Mann-Whitney for quantities variables in SPSS software.
Results:
22 subjects were excluded from the study. Both groups had no significant differences in age, sex, education, number of previous withdrawal and past history of other drug use. Result indicates decrease in objective withdrawal symptom significant in 3(p=0.000), 5 (p=0.004) and 7(p=0.026) day and subjective withdrawal symptom significant in 3 (p=0.000) day in topiramate groups.
Conclusion:
Topiramate can use for control of withdrawal symptom in patient with Heroin dependency.
The Swiss trials on medical prescription of injectable diacetylmorphine (pharmaceutical heroin) for “severe” heroin dependence provoked very controversial commentaries. Despite methodological shortcomings, the evaluation of the Swiss heroin trials yielded some interesting findings. Study participants showed substantial improvements in health and well-being and noticeable declines in illicit drug use and criminal activities. Heroin prescription may thus be helpful for some of those who continue to regularly use illicit heroin while maintained on methadone or who refuse other available treatment options. However, research-based evidence suggests that the intravenous (IV) application of heroin under medical supervision may have untoward side effects. Recent studies have shown that heroin injections produce transient, but significant decreases in systemic and cortical oxygenation most likely secondary to respiratory depression. Among others, these effects are the subject of ongoing studies.
Chronic opioid exposure is common world-wide, but behavioural performance remains under-investigated. This study aimed to investigate visuospatial memory performance in opioid-exposed and dependent clinical populations and its associations with measures of intelligence and cognitive impulsivity.
Methods
We recruited 109 participants: (i) patients with a history of opioid dependence due to chronic heroin use (n = 24), (ii) heroin users stabilised on methadone maintenance treatment (n = 29), (iii) participants with a history of chronic pain and prescribed tramadol and codeine (n = 28) and (iv) healthy controls (n = 28). The neuropsychological tasks from the Cambridge Neuropsychological Test Automated Battery included the Delayed Matching to Sample (DMS), Pattern Recognition Memory, Spatial Recognition Memory, Paired Associate Learning, Spatial Span Task, Spatial Working Memory and Cambridge Gambling Task. Pre-morbid general intelligence was assessed using the National Adult Reading Test.
Results
As hypothesised, this study identified the differential effects of chronic heroin and methadone exposures on neuropsychological measures of visuospatial memory (p < 0.01) that were independent of injecting behaviour and dependence status. The study also identified an improvement in DMS performance (specifically at longer delays) when the methadone group was compared with the heroin group and also when the heroin group was stabilised onto methadone. Results identified differential effects of chronic heroin and methadone exposures on various neuropsychological measures of visuospatial memory independently from addiction severity measures, such as injecting behaviour and dependence status.