HIV Sero-Status Non-disclosure Among HIV-Infected Opioid-Dependent Individuals: The Roles of HIV-Related Stigma, Risk Behavior, and Social Support.

HIV sero-status disclosure among people living with HIV (PLWH) is an important component of preventing HIV transmission to sexual partners. Due to various social, structural, and behavioral challenges, however, many HIV-infected opioid-dependent patients do not disclose their HIV status to all sexual partners. In this analysis, we therefore examined non-disclosure practices and correlates of non-disclosure among high-risk HIV-infected opioid-dependent individuals. HIV-infected opioid-dependent individuals who reported HIV-risk behaviors were enrolled (N = 133) and assessed for HIV disclosure, risk behaviors, health status, antiretroviral therapy (ART) adherence, HIV stigma, social support and other characteristics. Multivariable logistic regression was used to identify significant correlates of non-disclosure. Overall, 23% reported not disclosing their HIV status to sexual partners, who also had high levels of HIV risk: sharing of injection equipment (70.5%) and inconsistent condom use (93.5%). Independent correlates of HIV non-disclosure included: being virally suppressed (aOR 0.19, p = 0.04), high HIV-related stigma (aOR 2.37, p = 0.03), and having multiple sex partners (aOR 5.87, p = 0.04). Furthermore, a significant interaction between HIV-related stigma and living with family/friends suggests that those living with family/friends were more likely to report not disclosing their HIV status when higher levels of perceived stigma was present. Our findings support the need for future interventions to better address the impact of perceived stigma and HIV disclosure as it relates to risk behaviors among opioid-dependents patients in substance abuse treatment settings.

Ultrarapid Influence of Buprenorphine on Major Depression in Opioid-Dependent Patients: A Double Blind, Randomized Clinical Trial.

OBJECTIVE: To examine the impact of different doses of buprenorphine on depression symptoms in opioid dependent inpatient over a three-day interval, using a randomized clinical trial design (RCT). DESIGN: Patients were randomized and assigned to three groups. PARTICIPANTS: Forty males who were admitted to an inpatient psychiatric unit and who fulfilled the DSM-5 criteria for both opioid dependence and major depressive disorder. INTERVENTION: Patients randomly received 32 mg, 64 mg, or 96 mg of buprenorphine as a single high dose. Out of 40 patients, 11 (27.5%) received 32 mg, 14 (35%) received 64 mg and 15 (37.5%) received 96 mg of buprenorphine. We conducted medical precautional measures, including cardiovascular and respiratory monitoring. MEASUREMENTS: Depression was measured by the Beck Depression Inventory (BDI). All patients completed the three-day treatment duration. The results showed a significant reduction in depression symptoms within each of the three groups (p = 0.00), although there was no significant difference in depression outcome across the groups (p = 0.90). CONCLUSIONS: The results suggest that a single high dose of buprenorphine could provide a safe, simple and speedy means of depression improvement. A single high dose of buprenorphine can be used as medication that supplies a fast and maintained treatment for major depressive disorder in patients who are opioid dependent. Placebo-controlled trials of longer periods and larger sample sizes are needed to test ability and safety, as well as the physiological and psychological impact of extended exposure to this drug.

Tailoring a brief intervention for illicit drug use and alcohol use in Irish methadone maintained opiate dependent patients: a qualitative process.

BACKGROUND: The World Health Organization (WHO) recommend the tailoring of a brief intervention (BI) programme of research to ensure that it is both culturally and contextually appropriate for the country and the environment in which it is being tested. The majority of BI research has been conducted with non-opioid dependent participants. The current study developed a tailored BI for illicit drug use and alcohol use to a methadone maintained opioid dependent polydrug using cohort of patients. METHODS: Focus groups with staff and one-to-one qualitative interviews with patients guided the tailoring of all intervention materials for use in a subsequent cluster randomised controlled trial (RCT). This was done to make them contextually appropriate to an opioid dependent cohort and culturally appropriate to Ireland. Thematic analyses were utilised. RESULTS: The BI was modified to ensure its compatibility with the culture of an Irish drug using population, with elements of motivational interviewing (MI) and personalised feedback incorporated. Example scripts of a screening and BI were included, as was an algorithm to facilitate clinicians during a session. Modifications to the 'Substance Use Risk' cards included weighting the severity of the problems, writing the language in the first person to personalise the feedback and including tick boxes so as to further highlight the relevant risk factors for individual patients. Photographs of key risk factors were included to display pictorially risks for illiterate or semi-literate patients. Examples of the interaction of particular substances with methadone were of particular importance to this group. Modifications of the 'Pros and Cons of Substance Use/Reasons to Quit or Cut Down' included additional categories such as addiction, crime and money that were salient to this cohort. The manual was used to standardise training across trial sites. CONCLUSION: The research team was faithful to WHO recommendations to tailor BI programmes that are culturally and contextually appropriate to the treatment cohort and clinical environment. Outcome data from the cluster RCT have demonstrated that the tailored intervention was effective.

A comparison of characteristics and outcomes of opioid-dependent patients initiating office-based buprenorphine or methadone maintenance treatment.

BACKGROUND: The purpose of this study was to compare demographic factors and 1-year treatment outcomes of patients treated with buprenorphine or methadone. METHODS: The study included 252 subjects who received a prescription for buprenorphine in an academic internal medicine practice and 252 subjects who enrolled in a methadone maintenance program located on the same campus over the same time frame. Data were collected retrospectively. Patients were classified as "opioid-positive" or "opioid-negative" each month for a year based on urine drug testing and provider assessment. Successful treatment was defined as remaining in treatment after 1 year and achieving 6 or more opioid-negative months. RESULTS: Buprenorphine patients were more likely to be male, have health insurance, be employed, abuse prescription opioids, and be human immunodeficiency virus (HIV) infected; they were less likely to abuse benzodiazepines. At 12 months, 140 (55.6%) of buprenorphine patients and 156 (61.9%) of methadone patients remained in treatment (P =.148). Patients on methadone had a higher mean number of opioid-negative months (6.96 vs. 5.43; P <.001) and mean number of months in treatment (9.38 vs. 8.59; P <.001). On multivariable analysis, methadone maintenance was significantly associated with successful treatment (adjusted odds ratio: 2.10; 95% confidence interval: 1.43-3.07). CONCLUSIONS: Office-based buprenorphine and methadone maintenance programs serve very different populations. Both are effective, but patients on methadone had mildly better treatment outcomes.

Aripiprazole plus topiramate in opioid-dependent patients with schizoaffective disorder: an 8-week, open-label, uncontrolled, preliminary study.

BACKGROUND: The aims of this study were to evaluate a combination of aripiprazole and topiramate in the treatment of opioid-dependent patients with schizoaffective disorder undergoing methadone maintenance therapy (MMT) and, further, to taper off patients from methadone treatment. METHODS: Twenty patients who met DSM-IV (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition) criteria for opioid dependence and schizoaffective disorder receiving MMT (80 mg/day) were given aripiprazole (10 mg/day) plus topiramate (up to 200 mg/day) for 8 weeks. A methadone dose reduction of 3 mg/day until suspension at week 4 was established. RESULTS: Aripiprazole plus topiramate was effective in reducing clinical symptoms, and a rapid tapering off of MMT was achieved. CONCLUSIONS: Combining aripiprazole and topiramate may be effective in patients with a dual diagnosis of opioid dependency and schizoaffective disorder.

Persistence in the Methadone Maintenance Program and Its Relationship with the Medication Regimen Complexity Index in Opioid-Dependent Patients.

It has been shown that the Medication Regimen Complexity Index (MRCI) is a useful and reliable tool for calculating the complexity of the pharmacotherapeutic regimen (CPR). Furthermore, a high MRCI is associated with lower adherence. However, the MRCI of opioid-dependent patients (ODP) has not been studied. The aim of this study is to calculate the Methadone Maintenance Program (MMP) persistence and the MRCI score in a ODP cohort. Second, to analyze its relationship and association with other variables. To accomplish this research, an observational study including adults with a confirmed diagnosis of opiate-dependency according to the DSM-5 in a MMP center was carried out. To define MMP-persistence, a group was created by the researchers who defined five weighted items according to their agreed importance. Our first contribution was to create a new definition of MMP-persistence. This study also identified age, comorbidities, and received methadone maintenance doses as successful predictors for MMP-persistence. We have also shown that the MRCI does not seem to be a useful tool to determine MMP-persistence, probably because there are multiple factors that influence it in addition to the CPR. It is necessary to continue searching for more precise selection and stratification tools for ODP to improve their persistence.

Reconceptualizing Acute Pain Management in the 21st Century.

Acute pain can have many etiologies that include surgical procedures, trauma (motor vehicle accident), musculoskeletal injuries (rib fracture) and, burns among others. Valuable components of a multimodal approach to acute pain management include both opioid and non-opioid medications, procedure specific regional anesthesia techniques (peripheral nerve blocks and neuraxial approaches), and interventional approaches (eg, peripheral nerve stimulation and cryo-neurolysis). Overall, successful acute perioperative pain management requires a multimodal, multidisciplinary approach that involves a coordinated effort between the surgical team, the anesthesia team, nursing, and pharmacy staff using Enhanced Recovery After Surgery (ERAS) protocols.

The Impact of a Prenatal Education Program for Opioid-Dependent Mothers on Breastfeeding Rates of Infants at Risk for Neonatal Abstinence Syndrome.

INTRODUCTION: This study aimed to determine the effect of a prenatal education program for opioid-dependent women on breastfeeding frequency, newborn hospital length of stay, and cost of care for neonates at risk of developing neonatal abstinence syndrome. METHODS: From January 1, 2015 to January 1, 2020, opioid-dependent obstetric patients were educated on non-pharmacological preventative measures for neonatal abstinence syndrome (NAS), with focused counseling on breastfeeding. Data were collected and compared to a control group of opioid-dependent pregnant women who received standard care before initiation of the education program. RESULTS: Sample size calculation revealed that to detect doubling of the breastfeeding rate from 25% to 50% with 80% power and α error of 0.05, 66 participants were required in each group. CONCLUSION: There were 75 women with opioid use disorder who had prenatal NAS education (study group) and 108 women with opioid use disorder who underwent standard care before NAS education (control group). Prenatal NAS education participants significantly increased breastfeeding initiation rates compared to the control group. Newborn length of stay significantly decreased after initiation of prenatal NAS education compared to the 36 months before NAS education program.

Urinalysis based assessment of compliance and drug use patterns in patients prescribed tramadol: A cross-sectional study from a tertiary care centre.

BACKGROUND: Strict adherence to pharmacological dosage regimens is a prerequisite to the success of most treatments, particularly for patients in drug abuse programs. The compliance of tramadol, an atypical non-scheduled narcotic analgesic, using objective method has not been adequately studied in an Indian setting. AIM: To evaluate the compliance and pattern of drug use among opioid-dependent subjects prescribed tramadol based on urinalysis. METHOD: Fifty male opioid-dependent patients (ICD 10), seeking treatment at a tertiary de-addiction treatment centre of North India on tramadol prescription for atleast past four weeks were included. Self-reported substance use was recorded using semi-structured proforma. Ten ml of urine was collected for the assessment of compliance of tramadol of other substance use (morphine, buprenorphine, dextropropoxyphene, pentazocine, cannabis, benzodiazepines, pheniramine). All these drugs were analyzed using the immunoassay-based Cassette test and Gas Chromatography in human urine. RESULT: Mean age of the participants was 42.8 years and the mean duration of opioid use was 15.9years. The urine specimen of all subjects tested positive for tramadol. Urinalysis revealed benzodiazepines, cannabis, and pheniramine to be the most common substances of use in this population. It was seen that agreement of self-reporting and urine test results was good for morphine (κ = 0.558) and cannabis (κ = 0.312) and was poor for buprenorphine, pentazocine, and pheniramine. CONCLUSION: The study demonstrates the continued use of several illicit or non-prescribed medications in a medication-assisted opioid treatment population. The results affirm the reliability of urinalysis as an adjunct for testing compliance in such a population.

Evaluation of alcohol use pattern among OST patients using alcohol biomarkers: Report from community clinics in India.

Background: Opioid-dependent patients undergoing opioid substitution therapy (OST) consume alcohol in a hazardous pattern which adversely affects their treatment outcome. This study aims to measure alcohol biomarkers to screen for secondary alcohol use in OST patients. Methods: A pilot study was planned to measure alcohol biomarkers (AST, ALT, GGT, and CDT) to assess alcohol use in OST patients from three community clinics. The biomarkers were categorized based on the reported frequency of alcohol use. The association of the biomarkers with the frequency of alcohol consumption was determined using the post hoc (Mann-Whitney) test. Results: Forty-five patients with a mean (SD) age of 37.04 (10.7) years were included in the study. Alcohol intake was reported in daily, weekly, and monthly patterns by 22, 63, and 16% of the patients, respectively. High levels of ALT, GGT, and CDT were measured in patients with daily use of alcohol. Serum CDT levels significantly differentiate daily and weekly use from monthly consumption of alcohol. Conclusions: Alcohol biomarkers significantly predict the pattern of alcohol use among OST patients. These results can be prudent in low-resource community clinics to improve the overall outcomes of OST in India.

Developing a cognitive dysfunction risk score for use with opioid-dependent persons in drug treatment.

BACKGROUND: Cognitive dysfunction is common in persons seeking medication for opioid use disorder (MOUD) and may hinder many addiction-related services. Brief but accurate screening measures are needed to efficiently assess cognitive dysfunction in these resource-limited settings. The study aimed to develop a brief predictive risk score tailored for use among patients in drug treatment. METHODS: The present study examined predictors of mild cognitive impairment (MCI), objectively assessed via the NIH Toolbox, among 173 patients receiving methadone as MOUD at an urban New England drug treatment facility. Predictors of MCI were identified in one subsample using demographic characteristics, medical chart data, and selected items from the Brief Inventory of Neuro-Cognitive Impairment (BINI). Predictors were cross-validated in a second subsample using logistic regression. Receiver operating curve (ROC) analyses determined an optimal cut-off score for detecting MCI. RESULTS: A cognitive dysfunction risk score (CDRS) was calculated from patient demographics (age 50+, non-White ethnicity, less than high school education), medical and substance use chart data (history of head injury, overdose, psychiatric diagnosis, past year polysubstance use), and selected self-report items (BINI). The CDRS discriminated acceptably well, with a ROC curve area of 70.6 %, and correctly identified 78 % of MCI cases (sensitivity = 87.5 %; specificity = 55.6 %). CONCLUSIONS: The CDRS identified patients with cognitive challenges at a level likely to impede treatment engagement and/or key outcomes. The CDRS may assist in efficiently identifying patients with cognitive dysfunction while requiring minimal training and resources. Larger validation studies are needed in other clinical settings.

Willingness to initiate pre-exposure prophylaxis (PrEP) and its use among opioid-dependent individuals in drug treatment.

BACKGROUND: People who use drugs (PWUD) continue to experience a disproportionate HIV burden due to drug- and sex-related risk behaviors. Pre-exposure prophylaxis (PrEP) is highly effective at preventing HIV infection, but very little is known about PrEP use among PWUD and their willingness to initiate PrEP. METHODS: We conducted a cross-sectional survey among 234 HIV-negative, opioid-dependent individuals recruited from an urban methadone clinic. Participants were assessed using an audio-computer assisted self-interview technique. Bivariate and multiple logistic regressions were used to explore independent correlates of actual PrEP use and willingness to initiate PrEP. RESULTS: One-fourth (25.6 %) of participants had previously used PrEP. Over two-thirds (67.1 %) of participants had previously heard of PrEP, and 65.0 % were willing to take it. In multivariable logistic regression analyses, the number of times participants engaged in HIV testing (aOR = 1.66, p < 0.01) and whether they visited a healthcare provider (aOR=20.81, p = 0.02) were associated with a higher likelihood of PrEP use, while perceived HIV risk (aOR=2.71, p < 0.01) and previous use of PrEP (aOR=3.57, p < 0.01) were significantly associated with willingness to initiate PrEP. CONCLUSION: PrEP use was low among PWUD, but their willingness to initiate PrEP was moderate, which indicated a significant discrepancy between actual PrEP use and willingness to use it. Our findings highlight the importance of healthcare providers engaging opioid-dependent individuals in discussions about PrEP and the need for innovative strategies to increase their awareness of PrEP and modify their perceptions of HIV risk.

Post-cesarean delivery pain. Management of the opioid-dependent patient before, during and after cesarean delivery.

The opioid crisis has reached an unprecedented magnitude in the United States and worldwide, and data on opioid use and misuse in the obstetric population are extremely concerning. Despite an abundant number of studies evaluating strategies to prevent neonatal opioid withdrawal syndrome in babies born to mothers who are chronic opioid users, in babies born to mothers using chronic opioids, numerous questions remain unanswered, including (1) how to optimally manage postpartum pain in opioid-dependent patients (2) how to reconcile buprenorphine and methadone use with intrapartum and post-partum analgesia, so as to avoid opioid withdrawal during and after delivery (3) how to safely and effectively provide a stepwise multimodal approach that incorporates systemic opioid-sparing approaches, such as neuraxial opioids, clonidine, ketamine, gabapentin, and regional anesthetic blocks, to ensure adequate pain relief while avoiding opioid withdrawal (4) how to optimally manage post-partum recovery and (5) how to avoid excessive opioid prescription and possibly leftover opioids that may promote persistent use, misuse and diversion. With the recognition that an increasing number of pregnant women are taking chronic opioids, the goals of this review article are to summarize the existing literature on post-cesarean pain management in the obstetric patient with an opioid-use disorder; and to provide clinicians with a stepwise approach for management before, as well as during and after, cesarean delivery of women who have been chronically using opioids during their pregnancy.

A Longitudinal Qualitative Analysis of the Lived Experience of the Recovery Process in Opioid-Dependent Patients Post-Detoxification.

The aim of the study was to gain an in-depth understanding of opioid-dependent patients' lived experiences post-detoxification. METHOD: The study employed a naturalistic, observational longitudinal design, involving baseline screening and tracking of patients post-detoxification, with follow-up interviews at three, six, and nine months to observe specific processes of interest. This in-depth investigation of patients at four points was new within an Irish context and novel throughout the literature. FINDINGS: Recovery was seen as a process that was not always linear, and lapse and relapse were viewed as part of this process. Patients had great insight into "risk factors for relapse," information and knowledge gained over several years and many treatment episodes. Furthermore, the findings illustrate the role insight plays in any learning and growth experience and the emphasis that is placed upon it within the treatment journey; insight is a fundamental underpinning to any real growth and development. The current article argues that insight merits a more explicit role in the model of recovery capital.

A naturalistic longitudinal analysis of post-detoxification outcomes in opioid-dependent patients.

INTRODUCTION AND AIMS: To provide an assessment of outcomes in a cohort of opioid-dependent patients post-detoxification. DESIGN AND METHODS: This study employed an observational longitudinal cohort design. Patients who completed detoxification in the three major Drug Dependency Units in Ireland during a 14-month period were included in the study (n = 143). Patients opting for one of the three pathways post-detoxification (inpatient aftercare, outpatient aftercare or no formal aftercare) were assessed in the final week of detoxification and followed up after 3, 6 and 9 months. The primary outcome was abstinence following detoxification. RESULTS: A Cox (adjusted) model indicated participants who opted for outpatient aftercare treatment lapsed/relapsed at a rate of 52% higher than the inpatient aftercare group (hazard ratio = 1.52, 95% confidence interval 0.75-3.08, P = 0.24). Moreover, time to lapse/relapse was considerably shorter for the no formal aftercare group (hazard ratio = 7.68, 95% confidence interval 4.30-13.73, P = 5.75 × 10-12 ). Abstinence rates for outpatient aftercare and inpatient aftercare are about equal after 9 months. DISCUSSION AND CONCLUSION: Patients who opt for aftercare post-detoxification have significantly better outcomes at follow up when compared to no formal aftercare. In addition, patients' intention to attend aftercare affected their outcomes regardless of eventual treatment path.

Anxiety Treatment of Opioid Dependent Patients with Buprenorphine: A Randomized, Double-blind, Clinical Trial.

OBJECTIVE: The objective of this study is to examine the impact of vary doses of buprenorphine on anxiety symptoms in opioid-dependent inpatients over a 7 days period, using a randomized controlled trial design. DESIGN: Patients were randomized to three groups. PATIENTS AND METHODS: Fourteen men who met the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition criteria for both opioid use disorder and generalized anxiety disorder and were seeking for treatment. INTERVENTION: Patients obtain dosages of 32 mg or 64 mg or 96 mg of buprenorphine as a single dose only and were treated in a psychiatric inpatient unit. Of 14 subjects; 5 (35.7%) obtained 32 mg, 4 (28.6%) obtained 64 mg, and 5 (35.7%) obtained 96 mg of buprenorphine. MEASUREMENTS: Administering daily Hamilton Anxiety Rating Scale and interview. RESULTS: All the patients ended the 7-day treatment time. The results showed a significant reduction in anxiety symptoms within each of the three groups (P = 0.00), but no difference in outcome between the groups (P = 0.605). CONCLUSIONS: The outcome suggests a single high dose of buprenorphine can supply a speedy, safe, simple, and suitable means of anxiety treatment. The single high dose of buprenorphine could be a novel mechanism medication that provides a rapid and sustained improvement for generalized anxiety disorder in opioid dependent patients. Placebo-controlled trials of longer duration are needed to evaluate ability, safety, and psychological and physiological influence of extended exposure to this medication.

Using iPSC-derived human DA neurons from opioid-dependent subjects to study dopamine dynamics.

INTRODUCTION: The dopaminergic (DA) system plays important roles in addiction. However, human DA neurons from drug-dependent subjects were not available for study until recent development in inducible pluripotent stem cells (iPSCs) technology. METHODS: In this study, we produced DA neurons differentiated using iPSCs derived from opioid-dependent and control subjects carrying different 3' VNTR (variable number tandem repeat) polymorphism in the human dopamine transporter (DAT or SLC6A3). In addition, the effects of valproic acid (VPA) exposures on iPSC-derived human DA neurons are also examined. RESULTS: We present the first evidence suggesting that the 3' VNTR polymorphism in the hDAT gene affects DAT expression level in iPSC-derived human DA neurons. In human DA neurons, which provide an appropriate cellular milieu, VPA treatment alters the expression of several genes important for dopaminergic neuron function including DAT, Nurr1, and TH; this might partly explain its action in regulating addictive behaviors. VPA treatment also significantly increased DA D2 receptor (Drd2) expression, especially in the opioid-dependent iPSC cell lines. CONCLUSIONS: Our data suggest that human iPSC-derived DA neurons may be useful in in vitro experimental model to examine the effects of genetic variation in gene regulation, to examine the underlying mechanisms in neurological disorders including drug addiction, and to serve as a platform for therapeutic development.

Buprenorphine dose induction in non-opioid-tolerant pre-release prisoners.

BACKGROUND: In a previously reported randomized controlled trial, formerly opioid-dependent prisoners were more likely to enter community drug abuse treatment when they were inducted in prison onto buprenorphine/naloxone (hereafter called buprenorphine) than when they received counseling without buprenorphine in prison (47.5% vs. 33.7%, p=0.012) (Gordon et al., 2014). In this communication we report on the results of the induction schedule and the adverse event profile seen in pre-release prisoners inducted onto buprenorphine. METHOD: This paper examines the dose induction procedure, a comparison of the proposed versus actual doses given per week, and side effects reported for 104 adult participants who were randomized to buprenorphine treatment in prison. Self-reported side effects were analyzed using generalized estimated equations to determine changes over time in side effects. RESULTS: Study participants were inducted onto buprenorphine at a rate faster than the induction schedule. Of the 104 (72 males, 32 females) buprenorphine recipients, 64 (37 males, 27 females) remained on medication at release from prison. Nine participants (8.6%) discontinued buprenorphine because of unpleasant opioid side effects. There were no serious adverse events reported during the in-prison phase of the study. Constipation was the most frequent symptom reported (69 percent). CONCLUSION: Our findings suggest that buprenorphine administered to non-opioid-tolerant adults should be started at a lower, individualized dose than customarily used for adults actively using opioids, and that non-opioid-tolerant pre-release prisoners can be successfully inducted onto therapeutic doses prior to release.

The association between heroin expenditure and dopamine transporter availability--a single-photon emission computed tomography study.

One of the consequences of heroin dependency is a huge expenditure on drugs. This underlying economic expense may be a grave burden for heroin users and may lead to criminal behavior, which is a huge cost to society. The neuropsychological mechanism related to heroin purchase remains unclear. Based on recent findings and the established dopamine hypothesis of addiction, we speculated that expenditure on heroin and central dopamine activity may be associated. A total of 21 heroin users were enrolled in this study. The annual expenditure on heroin was assessed, and the availability of the dopamine transporter (DAT) was assessed by single-photon emission computed tomography (SPECT) using [(99m)TC]TRODAT-1. Parametric and nonparametric correlation analyses indicated that annual expenditure on heroin was significantly and negatively correlated with the availability of striatal DAT. After adjustment for potential confounders, the predictive power of DAT availability was significant. Striatal dopamine function may be associated with opioid purchasing behavior among heroin users, and the cycle of spiraling dysfunction in the dopamine reward system could play a role in this association.