High dose cocaine use in São Paulo: a comparison of treatment and community samples

Effectiveness of incorporating contingency management into a public treatment program for people who use crack cocaine in Brazil. A single-blind randomized controlled trial

BACKGROUND

Smoked cocaine (i.e., crack use) is a severe health problem in Brazil, with the country being reported as having the largest crack market in the world. The objective of this study was to evaluate the effectiveness of incorporating Contingency Management targeting cocaine abstinence into a public treatment program in Brazil.

METHODS

Single-blind randomized controlled trial conducted at Unidade Recomeço Helvétia (URH), a public ambulatory treatment program for persons who use crack and live in the "Crackland" region in downtown São Paulo, Brazil. In total, 98 treatment-seeking individuals who use crack were randomized to one of two treatment conditions. Participants allocated to the control condition (n = 48) received 12 weeks of the standard treatment provided at URH. Participants allocated to the experimental condition (n = 50) received the same treatment in combination with Contingency Management (URH+CM). In URH+CM, participants were provided with vouchers with monetary value for submission of negative cocaine urinalysis twice weekly.

RESULTS

Compared to the URH group, the URH+CM group was significantly more likely to submit a negative cocaine urinalysis during treatment, with odds ratios ranging from 4.17 to 6.78, depending on how missing data was accounted for (p<0.01). Participants receiving Contingency Management also had higher odds of achieving three or more weeks of continuous abstinence (OR= 8.07; 95% CI [2.48, 26.24]), achieved longer durations of abstinence (B = 2.14; 95% CI [0.67, 3.61]), submitted a higher percentage of negative urinalysis (B = 19.85; 95% CI [6.89, 32.82]), and were retained in treatment for a longer period (B = 3.00; 95% CI [1.04, 4.97]), compared to those receiving URH alone (p<0.01 for all).

CONCLUSIONS

The incorporation of Contingency Management was effective in promoting cocaine abstinence and treatment retention. The large-scale dissemination of Contingency Management may be an effective strategy to treat Brazilians with cocaine use disorders.

Following Up Crack Users after Hospital Discharge Using Record Linkage Methodology: An Alternative to Find Hidden Populations

This paper presents the probabilistic record linkage (PRL) methodology as an alternative way to find or follow up hard-to-reach population as crack users. PRL was based on secondary data from public health information systems and the strategy used from standardization; phonetic encoding and the rounds of matching data were described. A total of 293 patient records from medical database and two administrative datasets obtained from Ministry of Health Information Systems were used. Patient information from the medical database was the identifiers to the administrative datasets containing data on outpatient treatment and hospital admissions. 40% of patient records were found in the hospital database and 12% were found in the outpatient database; 95% of the patients were hospitalized up to 5 times, and only 10 out of them had outpatient information. The record linkage methodology by linking government databases may help to address research questions about the path of patients in the care network without spending time and financial resources with primary data collection.

Epigenetics, microRNA, and addiction

Drug addiction is characterized by uncontrolled drug consumption and high rates of relapse to drug taking during periods of attempted abstinence. Addiction is now largely considered a disorder of experience-dependent neuroplasticity, driven by remodeling of synapses in reward and motivation relevant brain circuits in response to a history of prolonged drug intake. Alterations in gene expression play a central role in addiction-relevant neuroplasticity, but the mechanisms by which additive drugs remodel brain motivation circuits remains unclear. MicroRNAs (miRNAs) are a class of noncoding RNA that can regulate the expression of large numbers of protein-coding mRNA transcripts by binding to the 3' untranslated region (3' UTR) of target transcripts and blocking their translation into the encoded protein or triggering their destabilization and degradation. Emerging evidence has implicated miRNAs in regulating addiction-relevant neuroplasticity in the brain, and in controlling the motivational properties of cocaine and other drugs of abuse. Here, the role for miRNAs in regulating basic aspects of neuronal function is reviewed. The involvement of miRNAs in controlling the motivational properties of addictive drugs is also summarized. Finally, mechanisms by which miRNAs exert their actions on drug intake, when known, are considered.

Exploring sex differences in drug use, health and service use characteristics among young urban crack users in Brazil

Introduction

Studies have shown important gender differences among drug (including crack) users related to: drug use patterns; health risks and consequences; criminal involvement; and service needs/use. Crack use is prevalent in Brazil; however, few comparative data by sex exist. We examined and compared by sex key drug use, health, socio-economic indicators and service use in a bi-city sample of young (18–24 years), regular and marginalized crack users in Brazil.

Methods

Study participants (total n = 159; n = 124 males and n = 35 females) were recruited by community-based methods from impoverished neighborhoods in Rio de Janeiro and Salvador. Assessments occurred by an anonymous interviewer-administered questionnaire and serum collection for blood-borne virus testing between November 2010 and June 2011. Descriptive statistics and differences for key variables by sex were computed; in addition, a ‘chi-squared automatic interaction detector’ (‘CHAID’) analysis explored potential primary factors differentiating male and female participants.

Results

Most participants were non-white, and had low education and multiple income sources. More women had unstable housing and income from sex work and/or panhandling/begging, whereas more men were employed. Both groups indicated multi-year histories of and frequent daily crack use, but virtually no drug injection histories. Men reported more co-use of other drugs. More women were: involved in sex-for-drug exchanges; Blood-Borne Virus (BBV) tested and HIV+. Both groups reported similar physical and mental health patterns; however women more commonly utilized social or health services. The CHAID analysis identified sex work; paid work; begging/panhandling; as well as physical and mental health status (all at p < 0.05) as primary differentiating factors by sex.

Conclusions

Crack users in our study showed notable differences by sex, including socio-economic indicators, drug co-use patterns, sex risks/work, BBV testing and status, and service utilization. Results emphasize the need for targeted special interventions and services for males and female crack users in Brazil.

Comparing key characteristics of young adult crack users in and out-of-treatment in Rio de Janeiro, Brazil

Background

Crack use is prevalent among street drug users in Brazilian cities, yet despite recent help system reforms and investments, treatment utilization is low. Other studies have identified a variety of – often inconsistent – factors associated with treatment status among crack or other drug users. This study compared socio-economic, drug use, health and service use characteristics between samples of young adult crack users in- and out-of-treatment in Rio de Janeiro, Brazil.

Findings

Street-involved crack users (n = 81) were recruited by community-based methods, and privately assessed by way of an anonymous interviewer-administered questionnaire as well as biological methods, following informed consent. In-treatment users (n = 30) were recruited from a public service in-patient treatment facility and assessed based on the same protocol. Key indicators of interest were statistically cross-compared. Not-in-treatment users were less likely to: be white, educated, stably housed, to be involved in drug dealing, to report lifetime marijuana and current alcohol use, to report low mental health status and general health or addiction/mental health care; they were more likely to: be involved in begging and utilize social services, compared to the in-treatment sample (statistical significance for differences set at p < .05).

Conclusions

In-treatment and not-in-treatment crack users differed on several key characteristics. Overall, in-treatment users appeared to be more socio-economically integrated and connected to the health system, yet not acutely needier in terms of health or drug problems. Given overall low treatment utilization but high need, efforts are required to facilitate improved treatment access and use for marginalized crack users in Brazil.

Anxiety symptoms in crack cocaine and inhalant users admitted to a psychiatric hospital in southern Brazil

OBJECTIVE

The occurrence of psychiatric comorbidity among individuals with crack or inhalant dependence is frequently observed. The objective of this study was to investigate anxiety symptoms among crack cocaine and inhalant users in southern Brazil.

METHODS

The study investigated two groups of volunteers of equal size (n=50): one group consisted of crack cocaine users, and the other group consisted of inhalant users. Research volunteers completed the Portuguese versions of the State-Trait Anxiety Inventory (STAI), Hamilton Anxiety Rating Scale (HAM-A), and Self-Report Questionnaire (SRQ).

RESULTS

Both crack and inhalant users experience significant symptoms of anxiety. Inhalant users presented significantly more anxiety symptoms than crack users according to the HAM-A questionnaire only. In contrast to the results of the HAM-A, the STAI failed to demonstrate a significant difference between the two groups of substance users. SRQ scores revealed that crack and inhalants users had significant degrees of morbidity.

CONCLUSION

A significant difference regarding anxiety symptomatology, especially state anxiety, was observed among inhalant and crack users. Anxiety and overall mental psychopathology were significantly correlated in this sample. The results indicate that screening initiatives to detect anxiety and additional psychiatric comorbidities among crack and inhalant users are feasible and relevant.

The relationship between lifetime stress and addiction severity in cocaine-dependent participants

OBJECTIVE

The primary focus of the current report was to determine if there was an association between LSC-R and ASI-Lite scores in cocaine-dependent individuals. The secondary focus was to determine if any demographic/drug use variables or comorbid psychiatric diagnoses (e.g. alcohol-dependence, mood disorders) were associated with higher LSC-R or ASI-Lite scores. We hypothesized that scores on the LSC-R would be positively correlated with ASI-Lite scores.

METHOD

The sample included 239 cocaine-dependent individuals. The primary assessments administered were the LSC-R, the ASI-Lite, and the demographic/drug use questionnaire.

RESULTS

Simple linear regression revealed that total lifetime stress was positively and significantly correlated with total ASI-Lite scores; however, the r(2) value was very low indicating that this relationship is more likely explained by other factors. It was also determined that participants with a diagnosis of alcohol dependence versus those that did not had significantly higher ASI-Lite scores (even when the alcohol composite score was included as a covariate). Participants with a diagnosis of a mood disorder versus those who did not had significantly higher LSC-R scores and females had significantly higher LSC-R scores when compared to males. After performing a median split, those cocaine users with High LSC scores had significantly higher Beck Depression Inventory-II scores, total ASI-Lite scores, and Fagerström Test of Nicotine Dependence scores when compared to those individuals with Low LSC scores. Further analysis of the ASI-Lite demonstrated that composite scores in the domains of Medical, Drug, Legal, Family and Social Status, and Psychiatric were all significantly elevated in the High LSC group.

CONCLUSIONS

Overall, those with higher lifetime stress demonstrated higher addiction severity and depressive symptoms versus those that endorsed lower lifetime stress. Thus, additional research should be conducted investigating the impact stressful life events has on drug use patterns and characteristics.

Molecular, cellular, and structural mechanisms of cocaine addiction: a key role for microRNAs

The rewarding properties of cocaine play a key role in establishing and maintaining the drug-taking habit. However, as exposure to cocaine increases, drug use can transition from controlled to compulsive. Importantly, very little is known about the neurobiological mechanisms that control this switch in drug use that defines addiction. MicroRNAs (miRNAs) are small non-protein coding RNA transcripts that can regulate the expression of messenger RNAs that code for proteins. Because of their highly pleiotropic nature, each miRNA has the potential to regulate hundreds or even thousands of protein-coding RNA transcripts. This property of miRNAs has generated considerable interest in their potential involvement in complex psychiatric disorders such as addiction, as each miRNA could potentially influence the many different molecular and cellular adaptations that arise in response to drug use that are hypothesized to drive the emergence of addiction. Here, we review recent evidence supporting a key role for miRNAs in the ventral striatum in regulating the rewarding and reinforcing properties of cocaine in animals with limited exposure to the drug. Moreover, we discuss evidence suggesting that miRNAs in the dorsal striatum control the escalation of drug intake in rats with extended cocaine access. These findings highlight the central role for miRNAs in drug-induced neuroplasticity in brain reward systems that drive the emergence of compulsive-like drug use in animals, and suggest that a better understanding of how miRNAs control drug intake will provide new insights into the neurobiology of drug addiction.

Early life exposure to violence and substance misuse in adulthood-The first Brazilian national survey

BACKGROUND

Substance misuse has been a major source of health and social problems in developing societies as it has been elsewhere. There is a growing body of evidence from developed nations linking early exposure to violence in childhood with substance misuse in adulthood. The role of depression on this association is not clear. This study estimates the association between early life exposure to violence, alcohol disorders and illegal substance use in adulthood and the role of depression on these associations using a national Brazilian sample.

METHODS

The first Brazilian National Alcohol Survey gathered information on early exposure to violence and use of psychoactive substances in 1880 participants aged 20 to 60 years old selected at random from the Brazilian household population. We used weighted logistic regression to calculate adjusted odds ratios for the associations between early exposure to violence and substance misuse. To assess the mediating effect of depression on these associations we used the Sobel-Goodman Mediation Test.

RESULTS

Witnessing violence during childhood or adolescence was reported by nearly 20% of the participants whilst over 8% reported having been victims of at least one form of violence. There was a statistically significant association between early exposure to violence and alcohol abuse and/or dependence and use of illegal substances in adulthood with a dose-response relationship. Depression partially explained the association between early exposure to violence with alcohol dependence (18.77% p<0.001) and did not have a statistically significant mediating effect on the association with illegal substance use (5.83% p=0.220).

CONCLUSIONS

Adverse early life events may affect individual's susceptibility to substance misuse which can be partially mediated by depression. Prevalence of substance misuse in adulthood may be in part attributed to the prevalence of adverse childhood experience. While prevention is the ideal goal, detection and intervention with children exposed to violence must be prioritised.

Sexual and drug use risk behaviors among children and youth in street circumstances in Porto Alegre, Brazil

We conducted a cross-sectional study to assess sexual and drug use risk in 161 children and youth in street circumstances in Porto Alegre, Brazil. Median age was 14 and 79% were male. Overall, 59% reported ever having had sex; a significantly higher proportion of males (66%) compared to females (30%). Overall, 39% reported illicit drug use in the last year, and only 1.2% reported injection drug use. In multivariate analyses, correlates of unsafe sex included younger age of sexual debut, and having a steady sex partner. Independent correlates of illicit drug use included lack of family contact, increased hours in the street daily, having had an HIV test, and older age. A high proportion of children and youth in street circumstances reported high risk sex and drug exposures, confirming their vulnerability to HIV/STD. Services Centers, such as where this research was carried out, offer an opportunity for interventions.

Drug Users' Participation in Addiction Care: Different Groups Do Different Things

This study allocated 201 (nearly) daily users of heroin and/or crack into four groups, depending on their addiction care participation. Earlier studies have compared treatment groups and nontreatment groups. In this study the treatment group is divided into three categories: (1) drug users in contact with only treatment agencies--i.e., methadone maintenance, clinical and ambulant drug treatment; (2) drugs users in contact with only care agencies--i.e., day and night shelters and drug consumption rooms, which have no explicit aims to change patterns of drug use; and (3) drug users in contact with both treatment and care agencies. This allocation intro three different groups fits the notion of harm reduction, one of the policy aims in The Netherlands. The fourth group consists of drug users in contact with neither treatment nor care agencies. The results show that it is useful to distinguish these four categories, instead of two. The four groups are different from each other with respect to some of their characteristics (e.g. debt situation, prostitution, homelessness) and their drug use (e.g. drug use in public, use of crack, and use of other drugs). A much clearer distinction can be made between the "care" group and the "treatment and care" group. Treatment and care agencies can thus better match their services to their clients or patients.

Concurrent crack and powder cocaine users from Sao Paulo: do they represent a different group?

BACKGROUND

Cocaine abuse is a serious and socially damaging illegal drug problem. Different routes of administration are associated with a specific progression of use, different degrees of abuse liability, propensity for dependence and treatment response. There have been relatively few studies comparing different cocaine users groups and no studies into the characterization of the group of individuals reporting concurrent use of powder cocaine and crack cocaine.

METHODS

Six hundred and ninety-nine cocaine users were assessed during the period August 1997 to October 1998 in one outpatient and six inpatient clinics located in the São Paulo, Brazil. Patients were interviewed using a structured questionnaire schedule in Portuguese, designed specifically for the Brazilian population. The statistical analyses were performed using either ANOVA or a chi-squared test and focusing on their preferred form of use/route of administration and other variables.

RESULTS

For 83% of the variables tested in this study, the Dual Users subgroup (using both powder and crack cocaine) demonstrated statistical differences from the single drug user subgroups. Those differences include the initiation of cocaine, the abuse of other illicit drugs, and rates of criminal history.

CONCLUSION

These data suggest cocaine-dependent individuals who report use of both powder and crack cocaine are an at least partially, distinct subgroup. However, further studies will be necessary to confirm this and to determine if they also show a different treatment response.

Transition to drug addiction: a negative reinforcement model based on an allostatic decrease in reward function

RATIONALE

The transition from initial drug use to drug addiction has been proposed to result from an allostatic decrease in reward function driven by an overactivation of brain antireward processes.

OBJECTIVES

How decreased reward function explains compulsive drug use is not entirely clear at present, and is still a subject for debate.

METHODS

We present a quantitative model of cocaine self-administration that integrates pharmacokinetic, pharmacodynamic, and motivational factors to address this question. The model assumes that reward system responsivity is a homeostatically regulated process where the desired level of responsivity (called the reward set point) is initially different from the baseline level. The reduction or correction of this difference or error in reward function would drive cocaine self-administration.

RESULTS

Theoretical data obtained by computer simulation fit the experimental data obtained in animals self-administering cocaine (i.e., the within-session pattern of self-injections, the shape and curvature of the dose-injection function, the nonlinear relationship between drug intake and regulated drug effects). Importantly, simulation of an allostatic decrease in reward system responsivity exacerbates the initial error that drives self-administration, thereby increasing both the intake of, and the motivation for, the drug. This allostatic change manifests as a vertical shift in the dose-injection function similar to that seen in animals with escalating cocaine self-administration.

CONCLUSIONS

The present model provides a satisfactory explanation of escalated drug intake and suggests a novel negative reinforcement view of addiction based on an allostatic decrease in reward function.

Effects of long-term, medically supervised, drug-free treatment and methadone maintenance treatment on drug users' emergency department use and hospitalization

We examined the effect of drug treatment in 1996 on repeated (> or =2) emergency department visits and hospitalization in 1997 in a cohort of New York State Medicaid-enrolled human immunodeficiency virus (HIV)-positive and HIV-negative drug users. In HIV-positive drug users, the adjusted odds of repeated emergency department visits were increased for those receiving no long-term treatment (odds ratio [OR], 1.65; 95% confidence interval [CI], 1.04-2.75), whereas the adjusted odds for those receiving methadone treatment and those receiving drug-free treatment for > or =6 months did not differ. The adjusted odds of hospitalization in the HIV-positive group were higher for those receiving long-term methadone treatment (OR, 1.69; 95% CI, 1.14-2.55) and for those receiving no long-term treatment (OR, 1.91; 95% CI, 1.29-2.88), compared with those receiving drug-free treatment. In the HIV-negative group, these associations were similar but weaker. For both HIV-positive and HIV-negative drug users, long-term drug-free treatment was at least as effective as long-term methadone treatment in reducing use of services indicative of poorer access to care and/or poorer health.

Factors associated with adverse reactions to cocaine among a sample of long-term, high-dose users in São Paulo, Brazil

This cross-sectional survey investigates the frequency of adverse cocaine reactions and associated factors among regular cocaine misusers. A sample of 332 cocaine misusers from a range of treatment and nontreatment settings in São Paulo, Brazil, were interviewed using a questionnaire that includes the Severity of Dependence Scale (SDS), the General Health Questionnaire (GHQ-28), the CAGE, and an eight-item questionnaire investigating the frequency of specific adverse cocaine reactions. The most commonly described reactions were hot flushes (84%), uncontrollable shaking (76%), and feeling ill (75%). The most severe symptoms and least common were convulsions or fits (18%) and passing out (21%). Frequency of adverse reactions to cocaine was positively associated with out-of-treatment status, severity of cocaine dependence, ever having injected cocaine, using tranquilisers with cocaine, and GHQ score. Adverse reactions to cocaine are common among regular cocaine users. Some of the adverse effects, especially those on the heart and central nervous system, are potentially fatal. Preventive strategies should be developed to reduce the risk of adverse cocaine reactions. The findings are discussed in relation to the type of interventions that might be developed and lines of future research.

A discussion of chain referral as a method of sampling hard-to-reach populations

Nursing research often requires inquiry into sensitive topics that involve hidden or hard- to reach populations. However, identifying and sampling these populations for research purposes is often fraught with difficulties. Barriers include society's lack of tolerance of diverse groups, social stigma, concern for issues of confidentiality, and fear of exposure because of possible threats to security. Chain referral sampling techniques are proposed to minimize bias while maintaining privacy and confidentiality. Techniques of chain referral sampling are detailed for use in researching sensitive topics and hidden populations. When carefully planned and executed, this sampling design offers transcultural nurse researchers a reasonable method for accessing and studying special populations that are particularly hard-to-reach.

Determining a diagnostic cut-off on the Severity of Dependence Scale (SDS) for cocaine dependence

AIM

The study aimed to assess the efficacy of the Severity of Dependence Scale (SDS) as a diagnostic measure of cocaine dependence and determine the cut-off score that best discriminates between the presence and absence of a DSM-IV diagnosis of cocaine dependence.

DESIGN

Cross-sectional survey.

SETTING

Sydney, Australia.

PARTICIPANTS

One hundred and forty-two cocaine users.

MEASUREMENTS

The diagnostic performance of the SDS was measured via ROC analysis against DSM-IV diagnoses of cocaine dependence, as measured by the Composite International Diagnostic Interview (CIDI).

FINDINGS

ROC analysis revealed the SDS to be a test of high diagnostic utility for the measurement of cocaine dependence. The cut-off point on the SDS at which there is optimal discrimination between the presence and absence of a DSM-IV diagnosis of cocaine dependence was found to be 3 (i.e. a score of 3 or more).

CONCLUSIONS

The study statistically validated the utility of the SDS as a diagnostic measure of cocaine dependence and has determined an appropriate cut-off point. The SDS is recommended as a brief screening instrument for cocaine dependence that can be used in addition to more comprehensive measures, such as the CIDI.