Drug misuse in alcoholics

Phencyclidine Positivity on Urine Drug Screening in Patients Treated for Alcohol Withdrawal on a Dual-diagnosis Medically Assisted Withdrawal Unit

OBJECTIVES

Little contemporary research has explored phencyclidine (PCP) use in people with alcohol use disorder. Therefore, we sought to determine the prevalence of PCP positivity on urine toxicology screening among patients admitted for alcohol withdrawal, identify correlates of PCP positivity, and investigate PCP positivity's relationship to length of stay (LOS) and risk of facility readmission.

METHODS

This was a retrospective study of patients admitted to a dual-diagnosis medically assisted withdrawal unit for alcohol withdrawal from 2014 to 2019. Univariate tests and logistic regression were used to investigate potential correlates of PCP positivity on admission toxicology screening (primary outcome). Multivariable linear regression models and survival analyses analyzing LOS and risk of readmission (secondary outcomes) were also developed.

RESULTS

Ninety of 3731 patients (2.4%) screened positive for PCP. There were significant associations on univariate testing between PCP positivity and age, race, homeless status, and urine toxicology positivity for amphetamines, benzodiazepines, barbiturates, cocaine, tetrahydrocannabinol, and oxycodone. On multivariate logistic regression, only tetrahydrocannabinol, barbiturates, and cocaine positivity were associated with PCP positivity. Multivariate logistic regression and survival analysis found no statistically significant associations between PCP positivity and LOS or risk of readmission.

CONCLUSIONS

This study provides rare analysis of contemporary data on PCP use among patients undergoing medically assisted alcohol withdrawal. Phencyclidine positivity was uncommon, but use appears considerably higher among this patient population than the general population. There was no significant association between PCP positivity and LOS or readmission risk.

Ethnic and Gender Differences in the Diagnostic Profiles of Substance Abusers

The aim of the study was to evaluate ethnic and gender differences in the diagnostic profiles of patients first admitted to the alcohol/drug rehabilitation unit of a state hospital. The majority of the patients (66%) had more than one diagnosis. African-American patients were significantly more likely to have a single diagnosis, however. In terms of primary diagnosis, Mexican Americans were more likely to have an alcoholrelated disorder while African-Americans were more likely to have a drug related disorder Drug-related disorders also complicate the diagnostic profile of African-American patients who had a primary diagnosis of an alcohol-related disorder Ethnic differences in type of drug abused were observed. African Americans were more likely to use stimulants/hallucinogens, and Mexican Americans were more likely to use depressants. A drug-related disorder was the most common diagnosis among females across all ethnic groups. Findings pointto the need of developing gender/ethnic-sensitive treatment programs. Potential ethnic and gender biases in the diagnostic evaluation of substance abuse patients are discussed.

Cocaine self-administration in Warsaw alcohol high-preferring (WHP) and Warsaw alcohol low-preferring (WLP) rats

Individuals prone to drug self-administration may be vulnerable not only to a single drug reinforcer but to a variety of drug reinforcers. It has been shown that two thirds of alcoholics regularly use drugs other than ethanol (alcohol). Up to 30% of alcohol-dependent patients report concurrent misuse of cocaine. The aim of the present study was to investigate intravenous cocaine self-administration in selectively bred, alcohol-preferring WHP (Warsaw high-preferring) and non-preferring WLP (Warsaw low-preferring) rats. It was hypothesized that WHPs could be more prone to cocaine self-administration in comparison to WLPs. Rats from both lines were allowed to nose-poke for cocaine infusions (0.33 mg/kg/infusion) under the FR-1, FR-2, and FR-3 schedule of reinforcement. Dose-response curves were assessed with increasing doses of cocaine (0.03, 0.1, 0.33, 1.0mg/kg/infusion). The WHP and WLP rats did not differ in cocaine self-administration. Both groups quickly acquired nose-poke responding for cocaine, presented a similar response profile when the schedule of reinforcement was increased from FR-1 to FR-3, and similar sensitivity to cocaine in the dose-response test. The present results may indicate that the selective breeding of alcohol-preferring WHP and alcohol non-preferring WLP rats did not lead to differences in cocaine's rewarding effects as assessed in the self-administration procedure.

The effect of cocaine on the expression of motor activity and conditioned place preference in high and low alcohol-preferring Wistar rats

Outbred rats show significant variability in their propensity to consume alcohol. These experiments were designed to examine the effect of cocaine on the expression of motor activation or place preference in outbred Wistar rats that consumed either high or low quantities of alcohol. These rats were exposed to a 2-bottle limited access procedure and dichotomized into 2 groups, high (mean 0.91 g/kg/h) and low alcohol consumption (0.36 g/kg/h), and then exposed to repeated daily cocaine, 10 or 20 mg/kg, or saline injections. The low alcohol-consuming rats showed a significant increase in motor behavior to a cocaine challenge across both doses of cocaine, which did not differ from each other. The high alcohol-consuming rats showed a significant increase in motor behavior only at the high dose of cocaine. In Experiment 2 both high and low alcohol-consuming rats were exposed to a conditioned place preference procedure using cocaine 10 mg/kg. High alcohol-consuming rats showed a significant place preference to the cocaine-paired side while low consuming rats did not. The differential effects of cocaine on motor activating behavior and reward obtained in these experiments suggest that those factors determining whether an outbred Wistar rat will consume high or low amounts of alcohol are related, in part, to differential sensitivity of those neural systems underlying the effects of those drugs.

The effect of gamma-vinyl-GABA on the consumption of concurrently available oral cocaine and ethanol in the rat

It has frequently been reported that a high percentage of individuals, identified as either alcohol- or cocaine-dependent, concurrently abuse both drugs. The experiments reported here represent a continuing effort to develop an animal model to predict the effects of a potential pharmacotherapeutic agent on concurrently available oral ethanol and cocaine. These experiments utilized drinkometer circuitry to assess the effects of gamma-vinyl-GABA (GVG), a gamma-aminobutyric acid (GABA) transaminase inhibitor, on the consumption and temporal pattern of responses for orally self-administered ethanol and cocaine. The results of these experiments showed that GVG, at doses of 100, 200 and 300 mg/kg, reduced both ethanol and cocaine consumption in a dose-related manner. When compared to vehicle, GVG at all doses significantly reduced ethanol consumption while consumption of cocaine was significantly reduced only at 300 mg/kg. This is consistent with data showing that GVG reduces consumption of these drugs when administered alone and data showing that GVG is more potent in reducing ethanol-induced compared to cocaine-induced extracellular dopamine in the nucleus accumbens. Analysis of the temporal pattern of drinking across the session suggests that GVG's effects are due to a disruption of the reinforcing properties of ethanol and cocaine rather than a more general reduction in motor behavior. These data suggest that GVG has potential for clinical use in populations that abuse either alcohol or cocaine alone or in combination.

Psychopharmacologic violence associated with cocaine abuse: kindling of a limbic dyscontrol syndrome?

1. An association of cocaine abuse with aggressive or violent behavior arising from direct pharmacologic effects of cocaine is demonstrable in the forensic and clinical literature. 2. The neurobehavioral basis for this association is considered form among known CNS actions of cocaine. A hypothesis is developed concerning the role of pharmacological kindling by cocaine that may sensitize for release of limbic-hypothalamic mechanisms of aggressive behavior, and for a drug-induced dyscontrol syndrome. 3. Parallels are drawn to kindling by electrical stimuli, and to neurophysiological research on mechanisms of aggression. 4. A role of concurrent hyperthermic effects of cocaine is suggested. 5. Potential contributions of cocaine actions on CNS serotonergic, catecholaminergic and/or adenosinergic systems are considered. 6. A likely role of concurrent ethanol ingestion to enhance the manifestation of cocaine-associated violence is recognized. 7. Pharmacological challenges, lidocaine or caffeine, are suggested as a means of detecting lowered thresholds of limbic excitability as a consequence of repeated cocaine exposures.

Drug use among primary alcoholic veterans

Many people with alcohol dependence use other drugs. However, not much is known about the relationship between their past drug use (not necessarily dependence) and their prognosis following treatment. The goal of this study is first to determine the drug use rates among primary alcoholic men and then to evaluate the possible relationship between past drug use and future alcohol or drug use relapse. As a result, 630 primary alcoholic veterans were recruited from a 28-day inpatient Alcohol and Drug Treatment Program at the San Diego VA Medical Center. Among them, almost two-thirds also had a history of drug use. Subjects were divided into the following four groups which were determined by their lifetime drug use histories: Group I (N = 226) consisted of drug abstainers, Group 2 (N = 142) was made up of alcoholics who had used only marijuana, Group 3 (N = 210) contained stimulant users who had never used opiates, and Group 4 (N = 52) included all opiate users. Comparisons of the four groups at a 3-month follow-up revealed that alcoholic men who had a history of stimulant or opiate use (Groups 3 and 4) were more likely to have had a drug use relapse. However, the four groups had similar alcohol relapse rates.