Search

Author(s): Ray, Lara A; Green, ReJoyce; Roche, Daniel J O; Bujarski, Spencer; Hartwell, Emily E; Lim, Aaron C; Rohrbaugh, Taylor; Ghahremani, Dara; Hutchison, Kent; Miotto, Karen | Abstract: Genetic variation in the endogenous opioid system has been identified as 1 potential source of individual variability in naltrexone treatment outcomes. The majority of naltrexone pharmacogenetic studies have focused on a particular single nucleotide polymorphism (SNP) of the mu-opioid receptor gene (OPRM1; rs1799971; commonly known as the Asn40Asp SNP) in Caucasian samples with decidedly mixed results. The goal of this study was to test the pharmacogenetic effects of naltrexone on subjective response to alcohol and self-administration of alcohol in individuals of East Asian descent. We hypothesized that naltrexone, compared with placebo, would potentiate the aversive and sedative effects of alcohol and reduce alcohol self-administration to a greater extent in Asp40 carriers.Participants (Nn=n77; Asn40Asn, nn=n29; Asn40Asp, nn=n34, and Asp40Asp, nn=n14) completed 2 double-blinded and counterbalanced experimental sessions: one after taking naltrexone (50nmg/d) for 5ndays and one after taking matched placebo for 5ndays. In each experimental session, participants received a priming dose of intravenous alcohol up to the breath alcohol concentration target of 0.06ng/dl which was immediately followed by an alcohol self-administration period (1nhour).There were no pharmacogenetic effects observed for alcohol-induced stimulation, sedation, craving for alcohol, or alcohol self-administration in the laboratory. During the self-administration period, Asp40 carriers consumed fewer drinks and had a longer latency to first drink as compared to Asn40 homozygotes.These findings in East Asians add to the mixed literature on naltrexone pharmacogenetics from predominantly Caucasian samples and highlight the complexity of these effects and their overall limited replicability. It is plausible that a consistent pharmacogenetic effect in tightly controlled preclinical and experimental medicine models "fades" in more complex and heterogeneous settings and samples.

Background and Objectives Opioids increase the risk for sleep disordered breathing (SDB), but there are few studies examining the prevalence and risk factors for SDB, specifically central sleep apnea (CSA), and obstructive sleep apnea (OSA) in chronic pain patients on opioids as well as methadone maintained patients (MMPs). Methods A literature review was conducted in which SDB was confirmed by polysomnography (PSG) in chronic pain patients on opioids as well as patients with a diagnosis of an opioid use disorder or opioid dependence on methadone maintenance treatment (MMT). Results About 22 reports were included. Six were with MMPs, and 16 were with chronic pain patients on opioids. Among MMPs, the prevalence of SDB ranged from 42.3% to 70%; 0–60% had CSA and 10–35.2% had OSA. In chronic pain patients on opioids, the prevalence of SDB ranged from 71% to 100%; 17–80% had CSA and 20–39% had OSA. In MMPs, studies found a positive association between BMI, weight gain, duration of MMT, non-Caucasian race and the number of obstructive apneas, as well as blood methadone concentrations and the number of central apneas. In chronic pain patients on opioids, older age, higher BMI, male gender, and higher opioid doses predicted more obstructive apneas; older age, lower BMI, male gender, higher pain levels, higher benzodiazepine doses, and higher opioid doses predicted more central apneas. Conclusion and Scientific Significance CSA and OSA are common in MMPs and chronic pain patients on opioids. Among chronic pain patients, higher opioid doses appear to be a risk factor for CSA, and to a lesser extent OSA. Therefore, it is important for providers to screen these patient populations for SDB. (Am J Addict 2016;25:452–465)

Background Subjective response to alcohol has been examined as a marker of alcoholism risk. The A118G single-nucleotide polymorphism (SNP) of the mu-opioid receptor (OPRM1) gene has been previously associated with subjective response to alcohol in heavy drinkers. This study seeks to extend the literature by examining the effect of OPRM1 genotype on responses to alcohol in a sample of alcohol-dependent individuals. A secondary aim of this study is to examine alcoholism severity as a predictor of subjective responses to alcohol. Methods Nontreatment seeking problem drinkers (n = 295) were assessed in the laboratory for clinical dimensions of alcohol dependence. Following prospective genotyping, 43 alcohol-dependent individuals across the 2 genotype conditions (AA, n = 23 and AG/GG, n = 20) were randomized to 2 intravenous infusion sessions: 1 of alcohol (target breath alcohol concentration = 0.06 g/dl) and 1 of saline. Measures of subjective responses to alcohol were administered in both infusion sessions. Results Alcohol-dependent G-allele carriers reported greater alcohol-induced stimulation, vigor, and positive mood, as compared to A-allele homozygotes. There was no genotype effect on alcohol-induced sedation or craving. There was a statistical trend-level severity × alcohol interaction such that individuals at higher levels of severity reported greater alcohol-induced tension reduction. Conclusions These results support the hypothesis that OPRM1 genotype moderates the hedonic effects of alcohol, but not the sedative and unpleasant effects of alcohol, in a sample of alcohol-dependent patients. Results are discussed in light of a clinical neuroscience framework to alcoholism.

Aims Withdrawal symptoms have been linked to a propensity for relapse to drug abuse. Inasmuch as this association applies to methamphetamine (MA) abuse, an understanding of the course of MA withdrawal symptoms may help to direct treatment for MA dependence. Previous studies of symptoms manifested during abstinence from MA have been limited in size and scope. We asked (i) whether debilitating psychological and/or physical symptoms appear during the first several weeks of MA abstinence, (ii) how craving for MA evolves and (iii) whether psychiatric symptoms (e.g. depression, psychosis) persist beyond a month of abstinence. Design A study of MA‐dependent participants, who initiated and maintained abstinence from the drug for up to 5 weeks, compared to a matched healthy comparison group. Setting In‐patient research hospital ward (MA‐dependent subjects) and out‐patient (comparison subjects). Participants Fifty‐six MA‐dependent and eighty‐nine comparison subjects. Measurements Rater‐assessed MA withdrawal questionnaire and self‐report assessment of craving (MA‐dependent subjects) and self‐report assessment of psychiatric symptoms (both groups). Findings At study entry, MA‐dependent subjects exhibited a wide range in severity of depressive symptoms, with the average score at a mild–moderate level of severity. Symptoms of psychosis were also prevalent. While depressive and psychotic symptoms largely resolved within a week of abstinence, craving did not decrease significantly from the time of initiating abstinence until the second week, and then continued at a reduced level to the fifth week. Conclusions Depressive and psychotic symptoms accompany acute withdrawal from methamphetamine but resolve within 1 week. Craving is also present and lasts at least 5 weeks.

Aims Previous research has reported that both contingency management (CM) and cognitive-behavioral therapy (CBT) are efficacious interventions for the treatment of stimulant abusers. The present study sought to directly compare the effectiveness of (CM) and (CBT) alone and in combination in reducing stimulant use. Design Randomized clinical trial. Participants Stimulant-dependent individuals (n = 171). Intervention CM, CBT or combined CM and CBT, 16-week treatment conditions. CM condition participants received vouchers for stimulant-free urine samples. CBT condition participants attended three 90-minute group sessions each week. Measurements Participants were interviewed at baseline and weeks 17, 26 and 52. Measures included psychiatric disorders and alcohol and drug use and concomitant social problems. Findings CM procedures produced better retention and lower rates of stimulant use during the study period. Self-reported stimulant use was reduced from baseline levels at all follow-up points for all groups and urinalysis data did not differ between groups at follow-up. While CM produced robust evidence of efficacy during treatment application, CBT produced comparable longer-term outcomes. There was no evidence of an additive effect when the two treatments were combined. Conclusions This study suggests that CM is an efficacious treatment for reducing stimulant use and is superior during treatment to a CBT approach. CM is useful in engaging substance abusers, retaining them in treatment and helping them achieve abstinence from stimulant use. CBT also reduces drug use from baseline levels and produces comparable outcomes on all measures at follow-up.

The clinical application of the narcotic antagonist, naltrexone for the treatment of opioid dependence has been minimal. This study evaluated the impact of a multi-component, manualized, psychosocial protocol designed to enhance the clinical value of naltrexone for opioid dependence treatment. Eighty-one detoxified individuals meeting DSM-IV criteria for opioid dependence were inducted onto naltrexone and randomly assigned to either a standard (ST) group, with monthly medical monitoring visits, or an enhanced (EN) group in which participants received counseling and educational interventions three times per week. EN group participants took more study medication, were retained in treatment longer, used less opioids while in treatment and showed greater improvement on a number of psychological/affective dimensions. The improved performance of the EN group was relatively short-lived as there were no significant group differences at 6- or 12-month post-admission follow-up points. \[Rawson RA, McCann MJ, Shopta...

Gamma-hydroxybutyric acid (GHB) is gaining popularity as a drug of abuse. Reports of toxicity and lethality associated with GHB use have increased. This survey study was designed to identify patterns of GHB use, its effects, and withdrawal syndrome. A survey inquiring about the effects of GHB was administered to 42 users. The results showed that GHB was used to increased feelings of euphoria, relaxation, and sexuality. Adverse effects occurred more frequently in daily users and polydrug users than in occasional GHB users. Loss of consciousness was reported by 66%, overdose by 28%, and amnesia by 13% of participants during GHB use and by 45% after GHB use. Three daily users developed a withdrawal syndrome that presented with anxiety, agitation, tremor, and delirium. Participants described GHB intoxication as having similarities to sedative-hypnotic or alcohol intoxication. Regular use has been shown to produce tolerance and dependence. Participants dependent on GHB reported using multiple daily doses around the clock. High frequency users appeared at the greatest risk for developing withdrawal delirium and psychosis after abrupt discontinuation of GHB use.

The authors examined characteristics of successful completers of an outpatient clonidine/oxazepam detoxification procedure for opioid dependence. Of 215 initial applicants, 167 received medication, and 65 successfully completed by taking a dose of naltrexone. Those who completed were more likely to have last used an opioid other than heroin, to be heroin smokers, rather than intravenous users, to have used benzodiazepines in the 30 days before treatment, and to have abstained from opioids for a longer time before presenting for treatment. New users (for less than 2 years) did no better than those using longer than 2 years. These findings may help in the continued refinement of patient placement criteria.

The authors examined characteristics of successful completers of an outpatient clonidine/oxazepam detoxification procedure for opioid dependence. Of 215 initial applicants, 167 received medication, and 65 successfully completed by taking a dose of naltrexone. Those who completed were more likely to have last used an opioid other than heroin, to be heroin smokers, rather than intravenous users, to have used benzodiazepines in the 30 days before treatment, and to have abstained from opioids for a longer time before presenting for treatment. New users (for less than 2 years) did no better than those using longer than 2 years. These findings may help in the continued refinement of patient placement criteria.