Glutamatergic neurons in ventral pallidum modulate heroin addiction via epithalamic innervation in rats.

Glutamatergic neurons in ventral pallidum (VPGlu) were recently reported to mediate motivational and emotional behavior, but its role in opioid addiction still remains to be elucidated. In this study we investigated the function of VPGlu in the context-dependent heroin taking and seeking behavior in male rats under the ABA renewal paradigm. By use of cell-type-specific fiber photometry, we showed that the calcium activity of VPGlu were inhibited during heroin self-administration and context-induced relapse, but activated after extinction in a new context. The drug seeking behavior was accompanied by the decreased calcium signal of VPGlu. Chemogenetic manipulation of VPGlu bidirectionally regulated heroin taking and seeking behavior. Anterograde tracing showed that the lateral habenula, one of the epithalamic structures, was the major output region of VPGlu, and its neuronal activity was consistent with VPGlu in different phases of heroin addiction and contributed to the motivation for heroin. VPGlu axon terminals in LHb exhibited dynamic activity in different phases of heroin addiction. Activation of VPGlu-LHb circuit reduced heroin seeking behavior during context-induced relapse. Furthermore, the balance of excitation/inhibition from VP to LHb was shifted to enhanced glutamate transmission after extinction of heroin seeking motivation. Overall, the present study demonstrated that the activity of VPGlu was involved in the regulation of heroin addiction and identified the VPGlu-LHb pathway as a potential intervention to reduce heroin seeking motivation.

Compulsivity and Inhibitory Control Deficits in Abstinent Individuals With Heroin Addiction and Their Biological Siblings Compared With Unrelated Healthy Control Participants.

BACKGROUND: Compulsivity represents the performance of persistent and repetitive acts despite negative consequences and is considered one of the critical mechanisms for drug addiction. Although compulsivity-related neurocognitive impairments have been linked to addiction, it remains unclear whether these deficits might have predated drug abuse as potential familial susceptibilities. METHODS: A large sample of 213 adult participants were recruited, including 70 abstinent individuals addicted to heroin (HAs), 69 unaffected biological siblings of the HAs (siblings), and 74 unrelated healthy control participants. Compulsivity-related neurocognitive functions were evaluated using the intradimensional/extradimensional set-shift task and a probabilistic reversal learning task. Compulsive traits were measured by the Obsessive-Compulsive Inventory-Revised. Inhibitory control was assessed using the stop signal task and Stroop Color and Word Test. Network models for group recognition were conducted using multilayer perceptron neural networks. RESULTS: Data indicated that both HAs and siblings performed worse than healthy control participants on compulsivity-related aspects (i.e., shifting and reversal learning functions) and inhibitory control and had higher levels of self-reported compulsive traits. Furthermore, neural models revealed that a possible 3-facet clustering of neurocognitive deficits was linked to both HAs and siblings. CONCLUSIONS: Our findings suggest that deficits in shift reversal and inhibitory control aspects and elevated compulsive traits, shared by HAs and their unaffected siblings, may putatively represent conceivable markers associated with familial vulnerabilities implicated in the development of heroin dependence.

The motives and methods of methamphetamine and 'heroin' co-use in West Virginia.

BACKGROUND: Opioid and methamphetamine co-use is increasing across the USA with overdoses involving these drugs also rising. West Virginia (WV) has led the US in opioid overdose death rates since at least 2013 and rising co-use of methamphetamine with opioids has played a greater role in deaths over the last 5 years. METHODS: This study used rapid ethnography to examine methods and motivations behind opioids and methamphetamine co-use from the viewpoint of their consumers. Participants (n = 30) were people who injected heroin/fentanyl also using methamphetamine who participated in semi-structured interviews. RESULTS: We found multiple methods of co-using opioids and methamphetamine, whether alternately or simultaneously and in varying order. Most prioritized opioids, with motives for using methamphetamine forming three thematic categories: 'intrinsic use', encompassing both inherent pleasure of combined use greater than using both drugs separately or for self-medication of particular conditions; 'opioid assisting use' in which methamphetamine helped people manage their existing heroin/fentanyl use; and 'reluctant or indifferent use' for social participation, reflecting methamphetamine's low cost and easy availability. CONCLUSIONS: Methamphetamine serves multiple functions among people using opioids in WV. Beliefs persist that methamphetamine can play a role in preventing and reversing opioid overdose, including some arguments for sequential use being protective of overdose. 'Reluctant' uptake attests to methamphetamine's social use and the influence of supply. The impact on overdose risk of the many varied co-use patterns needs further investigation.

Cognitive Enhancer Donepezil Attenuates Heroin-Seeking Behavior Induced by Cues in Rats.

PURPOSE: Opioid use disorder is a significant global problem. Chronic heroin use is associated with impairment of cognitive function and conscious control ability. The cholinergic system can be disrupted following heroin administration, indicating that activation of the cholinergic system may prevent chronic heroin misuse. Donepezil as an inhibitor of cholinesterase has been reported to clinically improve cognition and attention. In this study, the inhibition of heroin self-administration and heroin-seeking behaviours by donepezil were evaluated in rats. METHODS: Rats were trained to self-administer heroin every four hours for 14 consecutive days under a fixed ratio 1 (FR1) reinforcement schedule, then underwent withdrawal for two weeks. A progressive ratio schedule was then used to evaluate the relative motivational value of heroin reinforcement. After withdrawal, a conditioned cue was introduced for the reinstatement of heroin-seeking behaviour. Donepezil (0.3-3 mg/kg, i.p.) was used during both the FR1 heroin self-administration and progressive ratio schedules. Immunohistochemistry was used to investigate the mechanism of action of donepezil in the rat brain. RESULTS: Pre-treatment with high dose donepezil (3 mg/kg) but not low doses (0.3-1 mg/kg) significantly inhibited heroin self-administration under the FR1 schedule. Donepezil decreased motivation values under the progressive ratio schedule in a dose-dependent manner. All doses of donepezil (1-3 mg/kg) decreased the reinstatement of heroin seeking induced by cues. Correlation analysis indicated that the inhibition of donepezil on heroin-seeking behaviour was positively correlated with an increased expression of dopamine receptor 1 (D1R) and dopamine receptor 2 (D2R) in the nucleus accumbens (NAc) and increased expression of choline acetyltransferase (ChAT) in the ventral tegmental area (VTA). CONCLUSIONS: The present study demonstrated that donepezil could inhibit heroin intake and heroin-seeking behaviour. Further, donepezil could regulate dopamine receptors in the NAc via an increase of acetylcholine. These results suggested that donepezil could be developed as a potential approach for the treatment of heroin misuse.

Heroin use and neuropsychological impairments: comparison of intravenous and inhalational use.

BACKGROUND AND OBJECTIVES: Injection and inhalational heroin use are associated with different levels of brain exposure to heroin and its metabolites and differences in the severity of dependence, which might lead to differential impacts on neuropsychological functions. We examined the difference and the magnitude of difference in the neuropsychological functions between inhalational and injection heroin-dependent subjects and also compared them with healthy controls. METHODS: The study sample comprised three groups: 73 subjects with injection heroin dependence, 74 with inhalational heroin dependence, and 75 healthy controls (HC). We excluded patients with HIV, head injury, epilepsy, and severe mental illness. Neuropsychological assessments were done by Standard Progressive Matrices, Wisconsin Card Sorting Test (WCST), Iowa Gambling Task, Trail-Making Tests A and B (TMT), and Verbal and Visual Memory 1 and 2 Backtests (NBT). We estimated independent effects of the groups on various neuropsychological test parameters, adjusted for age and duration of dependence. RESULTS: In the WCST, the inhalational heroin-dependent group took more trials to complete the first category and had higher scores in the failure to maintain set than controls. The intravenous group had higher total errors than controls in verbal working memory tests and Visual Working Memory 2 Backtest. This group scored higher commission errors in the Verbal 2 Backtest than the controls. The two groups of heroin users differed in failure to maintain set and Verbal Working Memory 2 Backtests. The effect sizes of the group differences were modest. CONCLUSION AND SCIENTIFIC SIGNIFICANCE: Either route of heroin use is associated with cognitive impairments; inhalational and injection use involve different cognitive domains.

Relapse risk revealed by degree centrality and cluster analysis in heroin addicts undergoing methadone maintenance treatment.

BACKGROUND: 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.

Partial recovery of the left DLPFC-right insula circuit with reduced craving in abstinent heroin users: a longitudinal study.

The phenomenon of brain recovery after long-term abstinence has been reported in substance use disorders. However, few longitudinal studies have been conducted to observe the potential recovery in heroin users, and little is known about the neural mechanism underlying the decreased craving after prolonged abstinence. The 8-month longitudinal study was carried out in 29 heroin users and 30 healthy controls. By choosing the L_DLPFC, which was activated by the heroin cue as the seeding region, different brain connection patterns were compared between healthy controls and heroin users by using Granger causality analysis (GCA) at baseline. Then, a paired t test was employed to detect the potential recovery of L_DLPFC circuits after prolonged abstinence. The visual analog scale (VAS) and trail-making test-A (TMT-A) were adopted to investigate craving and cognitive control impairment, respectively. The neuroimaging changes were then correlated with behavioral improvements. Similar analyses were applied for the mirrored right DLPFC to verify the lateralization hypothesis of the DLPFC in addiction. In the longitudinal study, enhanced GCA coefficients were observed in the L_DLPFC-R_insula circuit of heroin users after long-term abstinence and were associated with craving score changes. At baseline, decreased GCA coefficients from the left DLPFC to the bilateral SMA and right putamen, together with the reduced GCA strength from the bilateral OFC to the left DLPFC, were found between HUs and HCs. Our findings extended the brain recovery phenomenon into the field of heroin and suggested that the increased regulation of the L_DLPFC over the insula after prolonged abstinence was important for craving inhibition.

Structural violence and the need for compassionate use of methadone in Mexico.

BACKGROUND: Epidemiological data from Mexico have documented an increase in heroin use in the last decade. However, there is no comprehensive care strategy for heroin users, especially those who have been accused of a crime. The objective of this study was to describe the heroin and methadone use of intravenous heroin users of both sexes who have been in jail, to offer evidence for the formulation of health policy. METHODS: This study used an ethnographic approach, with open-ended interviews carried out from 2014 to the present. Heroin users of both sexes attending a private methadone clinic in Mexico City were invited to participate. The sample was non-probabilistic. All interviews were audiotaped and transcribed, and narratives were analyzed using thematic analysis. RESULTS: Participants in this study were 33 users of heroin, two of them women, who had been in prison. They ranged in age from 33 to 62 years, had used heroin for a period of 13-30 years, and were from three states: Michoacan, Oaxaca, and Mexico City. Three principal categories of analysis were structured: 1. Pilgrimage for help (dynamics of the drama of suffering, pain, and time through health care spaces); 2) methadone use as self-care; and 3) accessibility to methadone treatment. The impossibility of access to methadone treatment is a condition which motivates users in their journey. The dynamics of methadone use are interpreted as a form of self-care and care to avoid substance use. Reducing the psychological, physical, and harmful effects of the substance allows them to perform daily activities. The inability to access treatment leads to a significant effect on users who experience structural violence. CONCLUSION: Compassionate methadone treatment and holistic attention should be considered as a way to meet patients' needs and mitigate their suffering, based on public health policy that allows for human rights-based care.

The discounting of death: Probability discounting of heroin use by fatal overdose likelihood and drug purity.

As fatal overdoses from synthetic opioids continue to rise, we need to understand decision-making processes underlying heroin and synthetic opioid use. This study evaluated the influence of sample impurity and fatal overdose risk on hypothetical heroin use. Individuals who currently use heroin (n = 69) were recruited online. Participants completed two probability-discounting tasks evaluating the likelihood of using a sample of heroin based on the likelihood of sample impurity and likelihood of fatal overdose, where greater discounting represented reduced use likelihood. Prior to completing the probability-discounting tasks, participants were randomized to read one of four prompts varying by the presence of information on heroin effects and active (e.g., fentanyl) or inert impurities. Influence of prompts on discounting processes and associations among probability-discounting measures, opioid use behaviors, and dependence severity were evaluated. Heroin use likelihood decreased with increased impurity or overdose risk and in a generally orderly fashion. Discounting was greater (i.e., reduced heroin use likelihood) when overdose risk, compared to sample impurity, was manipulated. Less discounting was associated with more severe opioid dependence. Discounting did not differ among prompts for either task. Individuals might adjust their heroin-use behavior to reduce harm with risk-related information. Greater discounting elicited by overdose relative to impurity risk suggests that equating adulteration and overdose risk is essential for harm reduction. Expanded access to drug checking services, which inform impurity and overdose risk, can reduce fatal overdoses. Due to fear of legal sanctions for these services, legislation and judicial decisions should explicitly protect these services. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Can the migration process influence the clinical expression of heroin use disorder in migrants to Italy?

BACKGROUND: For some time now, there has been a strong consensus that the migration process can influence the onset, course, development, outcome, and clinical aspects of psychiatric pathologies. METHODS: In this study, we have analyzed the influence of the migration process on the clinical expression of heroin use disorder (HUD). In a naturalistic case-control study, we compared, both at univariate and multivariate level, 30 migrant HUD (M-HUD) patients with 30 age/gender-matched Italian HUD (IT-HUD) patients. We also analyzed demographic data, drug addiction history, psychopathological symptoms, addictive behavior, and emotional reactivity to life events. RESULTS: Compared with IT-HUD pairs, at HUD Agonist Opioid Treatment, M-HUD patients were characterized by inadequate income and the presence of legal problems. They were more frequently at stage 3 of heroin addiction, with a concomitantly less frequent use of stimulants. Their age at the onset of heroin use was greater than that of subjects in the IT-HUD group. HUD post-traumatic stress disorder spectrum was present and was more severe in all M-HUD patients, but grief reactions and maladaptive behavior were the most discriminant traits. No differences were found in terms of addictive behaviors related to heroin craving or with respect to the severity/typology of psychopathology specific to HUD. CONCLUSIONS: The migratory process does not seem to be correlated with addictive behaviors or with psychopathology specific to HUD. It partly affects HUD history, and specifically correlates with emotional reactivity to loss and traumatic life events, so suggesting that in M-HUD individuals, the link between the migratory syndrome and HUD is very close.

Novel circuit biomarker of impulsivity and craving in male heroin-dependent individuals.

INTRODUCTION: The striatum mediates reward processing in addiction, and previous fMRI (functional Magnetic Resonance Imaging) studies have revealed abnormal striatofrontal functional connectivity in heroin addiction. However, little is known about whether there is abnormal structural connectivity of the striatal circuit in heroin addiction. This study investigated the structural connectivity of striatal circuits in abstinent heroin-dependent individuals (HDIs) without methadone treatment. METHODS: Forty-three (age: 38.8 ± 7.1) male HDIs and twenty-one (age: 42.4 ± 7.9) matched healthy controls underwent high-resolution T1 and whole-brain diffusion tensor imaging (64 directions) magnetic resonance imaging. Connectivity-based seed classification probabilistic tractography was used to detect the tract strengths of striatal circuits with 10 a priori target masks. Tract strengths were compared between groups and correlated with impulsivity behavior, evaluated using the Barratt Impulsivity Scale (BIS), and craving, measured on visual analogue scale (VAS). RESULTS: HDIs showed significantly weaker tract strength of the left striatum-medial orbitofrontal cortex (mOFC) (Bonferroni corrected, p < 0.05/20 = 0.0025) and significantly higher BIS total, attention, motor, and non-planning scores (Bonferroni corrected, p < 0.05/4 = 0.0125) than controls. In HDIs, negative correlations were observed between the left striatum- mOFC tract strengths and the BIS total, attention and non-planning scores (r1=-0.410, p1 = 0.005; r2=-0.432, p2 = 0.003; r3=-0.506, p3<0.001) and between the right striatum-posterior cingulate cortex (PCC) tract strengths and craving scores (r=-0.433, p = 0.009) in HDIs. CONCLUSION: HDIs displayed decreased structural connectivity of the striatum-mOFC circuit and higher impulsivity. Higher impulsive behavior was associated with decreased left striatal circuit connectivity. These findings suggest that the striatal circuit tract strengths might be a novel potential biomarker in heroin and, potentially, general opioid addiction.

Assessing the Role of Corticothalamic and Thalamo-Accumbens Projections in the Augmentation of Heroin Seeking in Chronically Food-Restricted Rats.

Drug addiction is a chronic disorder characterized by compulsive drug seeking, and involves repetitive cycles of compulsive drug use, abstinence, and relapse. In both human and animal models of addiction, chronic food restriction increases rates of relapse. Our laboratory has reported a robust increase in drug seeking following a period of withdrawal in chronically food-restricted rats compared with sated controls. Recently, we reported that activation of the paraventricular nucleus of the thalamus (PVT) abolished heroin seeking in chronically food-restricted rats. However, the precise inputs and outputs of the PVT that mediate this effect remain elusive. The goal of the current study was to determine the role of corticothalamic and thalamo-accumbens projections in the augmentation of heroin seeking induced by chronic food restriction. Male Long-Evans rats were trained to self-administer heroin for 10 d. Next, rats were removed from the self-administration chambers and were subjected to a 14 d withdrawal period while sated (unlimited access to food) or mildly food-restricted (FDR). On day 14, rats were returned to the self-administration context for a 3 h heroin-seeking test under extinction conditions during which corticothalamic and thalamo-accumbens neural activity was altered using chemogenetics. Surprisingly, chemogenetic activation or inhibition of corticothalamic projections did not alter heroin-seeking behavior. Chemogenetic activation of thalamo-accumbens shell, but not core, projectors attenuated heroin seeking in FDR rats. The results indicate an important role for the PVT to nucleus accumbens shell projections in the augmentation of heroin seeking induced by chronic food restriction.SIGNIFICANCE STATEMENT Relapse to heroin use is one of the major obstacles in the treatment of opiate addiction. Triggers for relapse are modulated by environmental challenges such as caloric restriction. Elucidating the brain mechanisms that underlie relapse is critical for evidence-based treatment development. Here we demonstrate a critical role for the input from the paraventricular thalamus (PVT), a hub for cortical, sensory, and limbic information, to the nucleus accumbens shell (an area known to be important for reward and motivation) in the augmentation of heroin seeking in food-restricted rats. Our findings highlight a previously unknown role for the PVT in heroin seeking following a period of abstinence.

Fifteen years of heroin-assisted treatment in a Swiss prison-a retrospective cohort study.

BACKGROUND: In the context of the current US opioid crisis and the compelling fact that a quarter to a third of all those addicted to heroin pass through its prisons and jails each year, the care of incarcerated opioid-using individuals (OUI) needs to be improved. AIMS: Little has been published on the effectiveness or outcomes of heroin-assisted treatment (HAT), a treatment option for severely dependent OUI delivered in a prison setting. The aim of this study was therefore to evaluate such treatment since its implementation. The primary objective was to investigate whether heroin-assisted treatment was associated with severe detrimental health outcomes. The secondary objective was to compare the heroin-assisted treatment group with the general prison population in terms of occupational functioning. DESIGN: Retrospective cohort study SETTING: An open prison with 120 places SUBJECTS: Data on 1885 male prisoners with a total of 2239 imprisonment periods between 2000 and 2015 was available. Ninety-seven inmates in heroin-assisted treatment were compared with 1788 inmates from the general prison population (reference group). MEASUREMENTS: Mortality, medical complications (including overdoses), and work performance (days worked, sick days, and monthly wages earned). FINDINGS: Inmates receiving HAT were on average 1 year younger (33.8 vs. 34.9 years), had longer prison stays (7.3 vs. 3.0 months), were more often of Swiss nationality (68.0% vs. 28.9%), and had committed more drug- and property-related offenses (49.5% vs. 23.2% and 63.9% vs. 38.3%, respectively) compared to the reference group. No serious heroin-related medical complication occurred during the 15-year window of observation among inmates with heroin-assisted treatment. Their work performance was comparable to that of the reference group. CONCLUSIONS: This study shows that heroin-assisted treatment can be a valuable treatment option for severely dependent OUI during imprisonment, can be delivered safely by prison health staff over extended periods of time, and allows OUI in treatment to achieve work performance rates comparable to that of the general prison population.

Measurement invariance and psychometric properties of Perceived Stigma toward People who use Substances (PSPS) among three types of substance use disorders: Heroin, amphetamine, and alcohol.

BACKGROUND: The 8-item self-report Perceived Stigma toward Substance Users Scale (PSAS) is a commonly used instrument to assess stigma for people with substance use disorders. This study aimed to develop and validate the Taiwan version of the PSAS entitled Perceived Stigma toward People who use Substances - Taiwan version (PSPS-TV) among individuals with substance use disorders. METHODS: Patients with substance use disorders (N = 300; mean age = 45.22; 255 males) completed the PSPS-TV, Self-Stigma Scale-Short (SSS-S), Taiwan Depression Questionnaire (TDQ), and Rosenberg Self-Esteem Scale (RSES). Confirmatory factor analysis was used to test the construct validity and the measurement invariance of the PSPS-TV. Concurrent validity was tested using the correlations between PSPS-TV and SSS-S, TDQ, and RSES scores. RESULTS: The confirmatory factor analysis supported the construct validity and measurement invariance of the PSPS-TV. SSS-S scores explained 13 %, TDQ scores explained 10 % and RSES scores explained 17 % of the PSPS-TV score variance with moderate standardized coefficients (0.38, 0.32 and -0.42, respectively; all p < 0.001). CONCLUSIONS: The PSPS-TV is an appropriate instrument to assess perceived stigma for individuals residing in Taiwan who have substance use disorders. Taiwan healthcare providers may thus consider using the PSPS-TV to assess perceived stigma relating to substance use in Taiwan.

Daily heroin injection and psychiatric disorders: A cross-sectional survey among People Who Inject Drugs (PWID) in Haiphong, Vietnam.

BACKGROUND: Psychiatric comorbidities are frequent among people who inject drugs, they are associated with a poorer prognosis and need to be addressed. Their interaction with daily heroin injection requires clarification. METHODS: A cross-sectional survey was conducted among PWID recruited in the city of Haiphong, Vietnam, by respondent-driven sampling. The inclusion criteria were age 18 or older and current injection drug use, verified by skin marks and positive urine tests for heroin or methamphetamine. Data on socio-demographic characteristics, drug use, sexual behaviour and access to treatment were collected using face-to-face questionnaires by trained interviewers. PWID were screened by trained psychiatrists for depression, psychotic disorder and suicidality, using the MINI questionnaire. RESULTS: 418 participants were included in the analyses. All were injected heroin users, 21 % were diagnosed with a current major depressive disorder, 15 % with a current psychotic disorder and 12 % presented a suicide risk. In the bivariate analyses, regular meth use, cannabis use and ketamine use were positively associated with presenting at least one psychiatric condition while daily heroin injection and being currently treated with methadone were negatively associated. In the multivariate model, poly-substance use was positively associated with depression (methamphetamine and drinking in addition to heroin) and psychotic disorder (methamphetamine and/or hazardous drinking in addition to heroin) while daily heroin injection and current methadone treatment were negatively and independently associated with depression and psychotic syndrome. CONCLUSIONS: Our survey confirms the burden of methamphetamine use and the protective effect of methadone but also a possible protective effect of daily heroin injection.

Suicide attempts and death among heroin-involved women seeking methadone treatment in Taiwan.

BACKGROUND: The present study aims to profile the hazard fluctuation of suicide attempts and deaths among heroin-involved women seeking methadone maintenance treatment (MMT) and to investigate sociodemographic and clinical factors predicting the time to have suicidal behaviors. METHODS: We identified a retrospective cohort comprising 2780 women receiving methadone treatment in the period of 2012-2016. Healthcare records were obtained from Taiwan's National Health Insurance Research Database, and suicide deaths were ascertained from the national death register. Competing risk survival analyses were used to estimate the risk of suicide attempts and deaths within one year and three years of MMT enrollment. RESULTS: A total of 1.2 % of MMT-treated women ever visited hospital for suicide attempt, and 0.5 % died by confirmed suicide. The risk of treated suicide attempt reached its peak at the end of the 8th month after methadone initiation, whereas the risk of confirmed suicide death was relatively stable during the first one and a half years. A history of treated depressive disorders appears to be the strongest risk predictor for treated suicide attempts (Adjusted Hazard Ratio [aHR] = 3.45; 95 % CI = 1.66-7.19) and confirmed suicide death (aHR = 3.47; 95 % CI = 1.20-10.0). Retaining in methadone treatment may significantly lower the hazard of probable suicide death by 52 %. CONCLUSIONS: Women with heroin use disorders should receive careful attention for suicide risk at intake assessment and over the course of treatment and recovery. Preventive strategies should target unmet clinical and social needs and evaluate gender-specific barriers for treatment engagement.

The Association between Opioid Discontinuation and Heroin Use: A Nested Case-Control Study.

BACKGROUND: Opioid prescribing guidelines recommend reducing or discontinuing opioids for chronic pain if harms of opioid treatment outweigh benefits. As opioid discontinuation becomes more prevalent, it is important to understand whether opioid discontinuation is associated with heroin use. In this study, we sought to assess the association between opioid discontinuation and heroin use documented in the medical record. METHODS: A matched nested case-control study was conducted in an integrated health plan and delivery system in Colorado. Patients receiving opioid therapy in the study period (January 2006-June 2018) were included. Opioid discontinuation was defined as ≥45 days with no opioids dispensed after initiating opioid therapy. The heroin use onset date represented the index date. Case patients were matched to up to 20 randomly selected patients without heroin use (control patients) by age, sex, calendar time, and time between initiating opioid therapy and the index date. Conditional logistic regression models estimated matched odds ratios (mOR) for the association between an opioid discontinuation prior to the index date and heroin use. RESULTS: Among 22,962 patients prescribed opioid therapy, 125 patients (0.54%) used heroin after initiating opioid therapy, of which 74 met criteria for inclusion in the analysis. The odds of opioid discontinuation were approximately two times higher in case patients (n = 74) than control patients (n = 1045; mOR = 2.19; 95% CI 1.27-3.78). CONCLUSIONS: Among patients prescribed chronic opioid therapy, the observed increased risk for heroin use associated with opioid discontinuation should be balanced with potential benefits.

Significant association of DRD2 and ANKK1 genes with rural heroin dependence and relapse in men.

INTRODUCTION: Substance abuse significantly influences human health and may induce problems with social functioning worldwide. Numerous genetic and environmental risk factors, as well as their interactions, accelerate the development of drug addiction. Etiologically, the dopaminergic mesocorticolimbic reward pathways are related to psychoactive substance addiction, and the reward properties of heroin are connected with changes in the mesolimbic dopaminergic system. OBJECTIVE: The aim of this study is a haplotypic analysis of subjects addicted to polysubstance. However, with the knowledge that this is not a homogenous subgroup, it was decided to separate and analyze homogenous subgroups of subjects in order to find specific haplotypic variants among them. The subjects in the subgroups were addicted to heroin, and subjects with more than two relapses in the past two years. MATERIAL AND METHODS: The study group comprised of 301 polysubstance addicted rural male subjects. From this group, 2 homogenous subgroups of subjects were isolated and additionally analyzed: (1) a group of heroin addicted subjects (n=61), and (2) a group of heroin-addicted subjects with at least two relapses in the last two years (n=21). The group consisting of all polysubstance addicted rural subjects and both homogenous subgroups were analyzed against a control group of non-addicted subjects (n=300), matching gender and age. Five polymorphisms in the DRD2/ANKK1 region were analyzed: rs1076560, rs1800498, rs1079597, rs6276 in the DRD2 gene, and rs1800497 in the ANKK1 gene. RESULTS: A statistically significant haplotype association was found in analysis of the heroin addicted subjects, compared to controls, and two possible trends - when comparing the whole group of addicted subjects to controls, and in relapse subgroups, compared to the controls. CONCLUSIONS: The results obtained showed that haplotypes indicate a part of the biological component of addiction.

Relationship between social capital and heroin use behaviors among patients in methadone maintenance treatment in Sichuan Province, China: A cross-sectional study.

Covertly using heroin during methadone maintenance treatment (MMT) is very common among heroin-dependent patients, which has posed threats to the physical health of heroin-dependent patients and social safety. Covertly using heroin may be influenced by many factors, especially social capital. Therefore, we aimed to investigate the relationship between behaviors of covertly using heroin during MMT and social capital heroin-dependent patients in Sichuan Province, China. A cross-sectional study was conducted between October and November 2018, with a total of 581 heroin-dependent patients participating in the study. In addition to socio-demographic characteristics and heroin use related behaviors, the questionnaire also included the measures of social capital: social network (SN), social support (SP), community participation (CP) and social trust (ST). Multivariate logistic regression analyses were used to estimate the association between different measures of social capital and heroin use. The prevalence of covertly using heroin of heroin during MMT was 31.0% among our participants in the 6 months before the study. After adjusting for socio-demographic factors and heroin-use related variables, SN (OR = 0.85, 95% CI: 0.76-0.95), SP (OR = 0.89, 95% CI: 0.83-0.95), and ST (OR = 0.88, 95% CI: 0.81-0.95) were significantly associated with heroin use. Results suggest that social capital may have a protective effect on behavior of covertly using heroin during MMT, which should be consider in the interventions for heroin-dependent patients, in order to reduce the incidence of heroin use during MMT as well as improve the compliance of MMT.