Addiction, Cocaine, Contingency Management, Substance Use Disorders
Conditions
Keywords
crack cocaine, contingency management, ambulatory treatment, Brazil
Brief summary
Crack addiction has become a severe public health problem in Brazil. Crack users present elevated prevalence rates of psychiatric comorbidities, sexual transmitted infections and unemployment with high probability of living or have lived in the streets, history of incarceration and engagement in illegal activities. For the last 20 years a treatment called Contingency Management (CM) have achieved the best results regarding reduction of substance use, promotion of abstinence, treatment attendance and retention in treatment. The first CM study conducted in Brazil advocates for the efficacy of CM on all of these outcomes, suggesting that CM can be effective in a Brazilian population of crack users.
Detailed description
The objective of this study is to evaluate the effectiveness of Contingency Management (CM) for crack users living in the Crackland region. To achieve this goal, regular treatment staff from Unidade Recomeço Helvétia treatment service will be capacitated in CM to latter-on apply the CM intervention in their respective services. The design will be a single-blind randomized clinical trial composed of a sample of 100 subjects with current diagnose for crack/cocaine dependence. Participants allocated to the control condition will receive 12 weeks of the usual care treatment provided by these two treatment facilities. Participants allocated to the experimental condition will receive the exact same treatment as control participants associated with CM. CM procedure will occur 2 timer per week (every Monday and Thursday or Tuesday and Friday). Primary outcomes are: (1)retention in treatment; (2) reduction of crack use; (3) promotion of continuous crack cocaine abstinence. Secondary findings are reduction on psychiatric symptomatology. The investigator hypothesis is that participants in the CM condition will have a better treatment response in all studied outcomes.
Interventions
BEHAVIORALContingency Management
Participants will receive vouchers with monetary value for submitting crack cocaine negative urine samples
BEHAVIORALStandard treatment
Participants will receive the standard treatment offered at Unidade Recomeço Helvétia treatment program
Sponsors
Washington State University
Federal University of São Paulo
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Investigator)
Masking description
researchers had no contact with participants during the 12 week trial
Intervention model description
Single-blind randomized controlled trial
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* DSM-V diagnose for crack cocaine use disorder
Exclusion criteria
* being under 18 years old
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Pattern of Crack Cocaine Use | 12 weeks | Percentage of negative crack cocaine urine samples submitted during the 12 weeks of treatment |
| Promotion of Continuous Crack Cocaine Abstinence | 12 weeks | Longest duration of continuous abstinence achieved (in weeks) |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Treatment Retention | 12 weeks | time elapsed between treatment entry and last time present in treatment (in weeks) |
Countries
Brazil
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Standard Treatment 12 weeks of standard treatment offered by Unidade Recomeço Helvétia treatment program
Standard treatment: Participants will receive the standard treatment offered at Unidade Recomeço Helvétia treatment program | 48 |
| Contingency Management 12 weeks of standard treatment offered at Unidade Recomeço Helvétia treatment program associated with Contingency Management
Contingency Management: Participants will receive vouchers with monetary value for submitting crack cocaine negative urine samples | 50 |
| Total | 98 |
Baseline characteristics
| Characteristic | Standard Treatment | Contingency Management | Total |
|---|---|---|---|
| Age, Continuous | 40.2 years STANDARD_DEVIATION 9.2 | 37.2 years STANDARD_DEVIATION 9 | 38.7 years STANDARD_DEVIATION 9.5 |
| Negative urine exam at baseline | 28 Participants | 22 Participants | 50 Participants |
| Race (NIH/OMB) American Indian or Alaska Native | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Asian | 1 Participants | 1 Participants | 2 Participants |
| Race (NIH/OMB) Black or African American | 26 Participants | 27 Participants | 53 Participants |
| Race (NIH/OMB) More than one race | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) White | 21 Participants | 22 Participants | 43 Participants |
| Region of Enrollment Brazil | 48 Participants | 50 Participants | 98 Participants |
| Sex: Female, Male Female | 8 Participants | 7 Participants | 15 Participants |
| Sex: Female, Male Male | 40 Participants | 43 Participants | 83 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 48 | 0 / 50 |
| other Total, other adverse events | 0 / 0 | 0 / 0 |
| serious Total, serious adverse events | 0 / 0 | 0 / 0 |
Outcome results
Primary
Pattern of Crack Cocaine Use
Percentage of negative crack cocaine urine samples submitted during the 12 weeks of treatment
Time frame: 12 weeks
Population: all enrolled participants were analyzed (intention to treat)
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Standard Treatment | Pattern of Crack Cocaine Use | 14.3 percent of negative cocaine samples | Standard Deviation 4.6 |
| Contingency Management | Pattern of Crack Cocaine Use | 40.7 percent of negative cocaine samples | Standard Deviation 5.8 |
Primary
Promotion of Continuous Crack Cocaine Abstinence
Longest duration of continuous abstinence achieved (in weeks)
Time frame: 12 weeks
Population: all participants enrolled in the study were analyzed (intention to treat)
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Standard Treatment | Promotion of Continuous Crack Cocaine Abstinence | 1.5 weeks | Standard Deviation 3.4 |
| Contingency Management | Promotion of Continuous Crack Cocaine Abstinence | 4.35 weeks | Standard Deviation 4.7 |
Secondary
Treatment Retention
time elapsed between treatment entry and last time present in treatment (in weeks)
Time frame: 12 weeks
Population: all participants enrolled in the study where analyzed (intention to treat)
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Standard Treatment | Treatment Retention | 3.4 weeks | Standard Deviation 4.8 |
| Contingency Management | Treatment Retention | 7 weeks | Standard Deviation 5.2 |