Powder and crack cocaine use among opioid users: is all cocaine the same?

OBJECTIVES: Problematic cocaine use is highly prevalent and is a significant public health concern. However, few investigations have distinguished between the 2 formulations of cocaine (ie, powder and crack cocaine) when examining the characteristics of cocaine use. Moreover, research has yet to assess the patterns of powder and crack cocaine use among opioid users, a clinical population in which problematic cocaine use is increasingly common. Using a within-subjects design, this study examined whether opioid users reported different patterns and features of powder and crack cocaine use, along with distinct trajectories and consequences of use. METHODS: Seventy-three clients enrolled in a low-threshold methadone maintenance treatment were interviewed regarding their lifetime use of powder and crack cocaine. RESULTS: Compared with crack cocaine, initiation and peak use of powder cocaine occurred at a significantly younger age. In relation to recent cocaine use, participants were significantly more likely to report using crack cocaine than using powder cocaine. Differences in routes of administration, polysubstance use, and criminal activity associated with cocaine use were also found between the 2 forms of cocaine. CONCLUSIONS: Results suggest that it may not be appropriate to consider powder and crack cocaine as diagnostically and clinically equivalent. As such, researchers may wish to distinguish explicitly between powder and crack cocaine when assessing the characteristics and patterns of cocaine use among substance users and treat these 2 forms of cocaine separately in analyses.

Outcome expectancy liking: a self-generated, self-coded measure predicts adolescent substance use trajectories.

This study tested the predictive validity of a novel, brief, and easy-to-use self-report measure of expectancies and their subjective values for alcohol and marijuana use. Canadian students in Grades 7 to 11 were administered paper-and-pencil questionnaires once per year for 3 consecutive years (Krank et al., 2011). As part of the questionnaire, participants completed an outcome expectancy measure where they were asked to list 3 or 4 things they expected would happen if they used a particular substance (i.e., alcohol, marijuana) and to indicate for each whether they would or would not like this outcome. "Liking" outcomes were coded as +1, "not like" as -1, and summed to obtain an outcome expectancy liking (OEL) sum for each participant and each substance. Participants also completed substance use behavior questions for alcohol and marijuana. Multilevel modeling demonstrated that OEL sum significantly predicted the intercept and slope of substance use trajectories by participants, even when demographic variables were controlled. For both alcohol and marijuana, multilevel modeling analyses indicated that a more positive OEL sum for a substance in the first year of the study were more likely to have tried that substance earlier (intercept) and were more likely to escalate their use at a greater rate over time (slope). The results complement the predictive validity found with other direct and indirect measures of substance use associations. The outcome expectancy liking task is a simple and unobtrusive method for identifying adolescents who are at risk for early substance abuse.

Prescription opioid misuse: characteristics of earliest and most recent memory of hydromorphone use.

OBJECTIVES: Prescription opioid use is highly prevalent and a major physician concern. However, little is known about how individuals initiate into use of these medications or how they use them later in life. Hydromorphone is a medication of particular interest given its subjective similarities to heroin and tendency to be misused by illicit opioid users. The purpose of this study was to evaluate the characteristics of initial, and more recent, hydromorphone use occasions as remembered by a population of individuals in treatment for their opioid use. METHODS: Seventy-eight clients enrolled in low-threshold methadone maintenance treatment were interviewed regarding their earliest and most recent uses of hydromorphone. RESULTS: Hydromorphone was first used after trying many different substances (eg, tobacco, alcohol, hallucinogens, powder cocaine). Two-thirds of the sample reported initially using hydromorphone without a prescription. Participants who initially used hydromorphone without a prescription reported using for different reasons (ie, to get high, curiosity vs manage pain), via different routes of administration (ie, injection vs orally), and were more likely to co-use other substances, than those whose earliest hydromorphone use was prescribed. However, these 2 subgroups did not differ greatly during their most recent use occasion (ie, the majority reported using to avoid withdrawal, via injection; almost 50% reported co-use with other substances). CONCLUSIONS: There was considerable variability in characteristics of hydromorphone use initiation among individuals enrolled in low-threshold methadone maintenance treatment. However, later use of hydromorphone was remarkably consistent across individuals and shares many characteristics previously documented for heroin use. Additional investigations into hydromorphone are warranted, particularly given previous findings regarding the prevalence of nonmedical use of this drug and its similarities to heroin.

The relationship between self-reported substance use and psychiatric symptoms in low-threshold methadone maintenance treatment clients.

BACKGROUND: Ongoing psychiatric symptoms and substance use are common difficulties experienced by clients enrolled in methadone maintenance treatment (MMT). However, little research to date has evaluated if specific types of current substance use are related to specific types of current psychiatric symptoms. The present study investigated these relationships with a sample of clients enrolled in a low-threshold MMT program (i.e., clients are not expelled if they continue to use substances). Some clients enrolled in low-threshold programs may never achieve complete abstinence from all substances. Thus, understanding the possibly perpetuating relationships between concurrent substance use and psychiatric symptoms is important. Understanding such relationships may aid in developing possible target areas of treatment to reduce substance use and/or related harms in this population. METHODS: Seventy-seven individuals were interviewed regarding methadone usage and current and past substance use. Current psychiatric symptoms were assessed using a modified version of the Psychiatric Diagnostic Screening Questionnaire (PDSQ). Relationships between types of substances used in the past 30 days and the types and number of psychiatric symptoms experienced in the same timeframe were examined. RESULTS: The majority of participants (87.0%) reported using alcohol, illicit substances, non-prescribed prescription opioids, or non-prescribed benzodiazepines in the past 30 days and 77.9% of participants reported currently experiencing psychiatric symptoms at levels that would likely warrant diagnosis. Current non-prescribed benzodiazepine use was a predictor for increased severity (i.e., symptom count) of almost all anxiety and mood disorders assessed. Conversely, number and presence of generalized anxiety symptoms and presence of social phobia symptoms predicted current non-prescribed benzodiazepine and alcohol use, respectively. CONCLUSIONS: Individuals enrolled in the present low-threshold MMT program experience a wide variety of psychiatric symptoms and continue to use a variety of substances, including opioids. There was a particularly consistent pattern of associations between non-prescribed benzodiazepine use and a variety of psychiatric symptoms (particularly anxiety) suggesting that addressing concurrent illicit benzodiazepine use and anxiety symptoms in MMT clients warrants further clinical attention and research.

Diffusion tensor imaging and olfactory identification testing in early-stage Parkinson's disease.

Evidence from imaging, clinical studies, and pathology suggests that Parkinson's disease is preceded by a prodromal stage that predates clinical diagnosis by several years but there is no established method for detecting this stage. Olfactory impairment, which is common in Parkinson's disease and often predates clinical diagnosis, may be a useful biomarker for early Parkinson's. Evidence is emerging that diffusion imaging parameters might be altered in olfactory tract and substantia nigra in the early stages of clinical Parkinson's disease, possibly reflecting pathological changes. However, no study has examined olfaction and diffusion imaging in olfactory tract and substantia nigra in the same group of patients. The present study compared newly diagnosed Parkinson's disease patients with a matched control group using both olfactory testing and diffusion tensor imaging of the substantia nigra and anterior olfactory structures. Fourteen patients with stage 1-2 Hoehn & Yahr Parkinson's disease were matched to a control group by age and sex. All subjects then completed the University of Pennsylvania Smell Identification Test, as well as a series of MRI scans designed to examine diffusion characteristics of the olfactory tract and the substantia nigra. Olfactory testing revealed significant impairment in the patient group. Diffusion tensor imaging revealed significant group differences in both the substantia nigra and anterior olfactory region, with fractional anisotropy of the olfactory region clearly distinguishing the Parkinson's subjects from controls. This study suggests that there may be value in combining behavioral (olfaction) and MRI testing to identify early Parkinson's disease. Since loss of olfaction often precedes the motor symptoms in Parkinson's disease, the important question raised is "will the combination of olfactory testing and MRI (DTI) testing identify pre-motor Parkinson's disease?"

Energy drink co-administration is associated with increased reported alcohol ingestion.

INTRODUCTION AND AIMS: While energy drinks (EDs) and alcohol have been reported to be frequently co-administered, little is known about the effect of this co-administration on alcohol drinking patterns. The purpose of the present research was to characterise patterns of ED and alcohol co-administration. DESIGN AND METHODS: Seventy-two ED users were recruited from the Halifax university community. Participants provided information about their lifetime ED and other substance use, in addition to detailing instances of their ED and alcohol use during the previous week using a timeline follow-back interview. RESULTS: Seventy-six per cent of participants reported ever deliberately mixing alcohol with EDs and 19% reported doing so during the previous week. Relative to alcohol drinking sessions in which EDs were not used, participants reported drinking significantly more alcohol when it was co-administered with EDs. DISCUSSION AND CONCLUSIONS: Alcohol and ED co-administration is relatively common among ED users and seems to be associated with increased alcohol ingestion. It is recommended that this matter receive more clinical and research attention.

A further investigation of the relations of anxiety sensitivity to smoking motives.

Prior research has shown that anxiety sensitivity (AS) is associated with smoking to reduce negative affect (e.g., [Comeau, N., Stewart, S.H., & Loba, P., (2001). The relations of trait anxiety, anxiety sensitivity and sensation seeking to adolescents' motivations for alcohol, cigarette, and marijuana use. Addictive Behaviors, 26, 803-825.]). However, given limitations in the measurement of smoking motives in previous AS studies, it has yet to be definitively established that AS is specifically related to negative reinforcement smoking motives. Moreover, the overall AS construct is comprised of three lower-order components: physical, psychological, and social concerns (e.g., [Stewart, S.H., Taylor, S., & Baker, J.M., (1997). Gender differences in dimensions of anxiety sensitivity. Journal of Anxiety Disorders, 11, 179-200.]). Previous investigations generally have not examined the relative contributions of each of these three AS components to smoking for negative reinforcement motives. The present study attempted to address each of these gaps in the literature. A sample of 119 smokers attending a tobacco intervention program (see [Mullane, J.C., Stewart, S.H., Rhyno, E., Steeves, D., Watt, M., & Eisner, A., (2008). Anxiety sensitivity and difficulties with smoking cessation. In A.M. Columbus (Ed.), Advances in Psychological Research (vol. 54A, pp. 141-155). Hauppauge, NY: Nova Science Publishers.]) completed the Anxiety Sensitivity Index (ASI; [Peterson, R.A., & Reiss, S., (1992). The Anxiety Sensitivity Index manual (2nd ed.). Worthington, OH: International Diagnostic Services.]) and the Reasons For Smoking scale (RFS; [Ikard, F.F., Green, D.E., & Horn, D., (1969). A scale to differentiate between types of smoking as related to the management of affect. International Journal of the Addictions, 4, 649-659.]) at pre-treatment. In a principal components analysis (PCA) of the RFS items, stringent parallel analysis supported a two-factor solution (negative and positive reinforcement smoking motives) as opposed to the intended six factors ([Ikard, F.F., Green, D.E., & Horn, D., (1969). A scale to differentiate between types of smoking as related to the management of affect. International Journal of the Addictions, 4, 649-659.]). ASI total scores were significantly positively correlated with both RFS factors in bivariate correlational analyses. In partial correlations, the relation between the ASI and the RFS negative reinforcement factor remained significant when controlling for RFS positive reinforcement smoking motives, but the correlation of ASI with RFS positive reinforcement motives was not significant after controlling for RFS negative reinforcement motives. At the level of AS components, AS psychological concerns were related to both negative and positive reinforcement motives, while AS physical concerns were more strongly related to negative reinforcement motives. Implications for designing targeted tobacco interventions for high AS smokers are discussed.