Contingency Management Treatment for Crack Addiction - Study With Brazilian Population

Evaluating the Efficacy of Including Contingency Management to Standard Ambulatory Treatment for Crack Addiction - A Randomized Controlled Trial

Crack addiction has become a severe health problem in Brazil. Today, crack addiction is the primary cause for inpatient treatment for all illicit substances. When compared to cocaine, crack users develop much faster diagnoses for crack dependence, shows a more compulsive pattern of use, has higher probability of living or have lived in the streets, and of engaging in illegal activities. Consequently to this, mortality of crack addicts is 7 times higher than for the rest of the population. Despite all efforts being made for the development of effective pharmacological treatments for stimulant addiction (crack included), up to today, there is no robust evidence of efficacy of any pharmacological treatment. For that reason, the use of evidence based psychosocial interventions is so important for treating this population. Although today open treatment facilities in Brazil are more and more starting to use evidence-based interventions such as motivational interviewing, cognitive behavior therapy, relapse prevention and coping skills, such treatments present very modest results when treating crack addiction. The biggest difficulties encountered when treating this population are maintaining patients in treatment, reducing crack use and achieving continued abstinence. A psychosocial treatment based in behavioral principals' named Contingency Management (CM) is widely applied in the USA. Recent meta-analyses and review studies present robust evidence that, when applied alone or in adjunction with other psychosocial and pharmacological treatment, CM is the most effective treatment for what regards, treatment retention, reducing drug use and promoting continued abstinence. The purpose of this study is to evaluate if Contingence Management (CM) can be affective in the treatment of crack addiction in Brazil. To accomplish this, 60 individuals (male and female from 18 to 65 years of age) seeking open treatment for crack addiction will be randomized to 2 treatment conditions (Standard treatment (ST) or ST+CM. Both treatments will last 12 weeks with 3 and 6-month follow-up. In both groups patients will be encourage to leave urine samples 3 times week. Hypotheses: Patients receiving ST+CM will stay longer in treatment, have more negative tests for cocaine/crack, and achieve longer periods of cocaine/crack abstinence when compared to patients receiving ST alone.

This study is a Randomized Clinical Trial deigned to investigate the effects of including Contingency Management to a standard public ambulatory treatment in Brazil on treatment attendance, retention in treatment, reduction of crack cocaine use and promotion of crack cocaine abstinence for crack dependent individuals seeking treatment for there addiction. In total 65 subjects will be randomized to receive Standard Treatment Alone or Standard Treatment plus Contingency Management. Both interventions will last for 12 weeks.

Participants in the Standard Treatment Alone group will receive 12 weeks of the exact treatment provided by the Ambulatory service where the study is being conducted

Participants in the Standard treatment plus Contingency Management (ST+CM) group will receive 12 weeks of the exact treatment provided by the Ambulatory service where the study is being conducted plus CM.

12 weeks of the standard treatment offered by a open treatment service for drug addiction of the city of Sao Paulo (AME) plus Contingency Management

12 weeks of standard treatment offered by AME (a open treatment service for drug addiction of the city of Sao Paulo)

Retention in treatment was quantified as the period elapsed between treatment intake and dropout (last appearance at the treatment facility) or the end of treatment. We present data on the number of participants retained in treatment in weeks 4, 8 and 12.

Treatment attendance was expressed as the total number of sessions attended during the 12 weeks of treatment.

The proportion of samples testing negative for marijuana was determined by dividing the number of negative samples by the total number of expected samples (36 samples)

Inclusion Criteria: Current diagnose of crack addiction (DSM IV) having used crack in the last month Exclusion Criteria: Current psychotic disorder Diagnose of schizophrenia

Miguel AQ, Madruga CS, Cogo-Moreira H, Yamauchi R, Simoes V, da Silva CJ, McPherson S, Roll JM, Laranjeira RR. Contingency management is effective in promoting abstinence and retention in treatment among crack cocaine users in Brazil: A randomized controlled trial. Psychol Addict Behav. 2016 Aug;30(5):536-543. doi: 10.1037/adb0000192. Epub 2016 Jul 21.

de Queiroz Constantino Miguel A, Sandi Madruga C, Simoes V, Yamauchi R, da Silva CJ, McDonell M, McPherson S, Roll J, Laranjeira RR, de Jesus Mari J. Contingency management is effective in promoting abstinence and retention in treatment among crack cocaine users with a previous history of poor treatment response: a crossover trial. Psicol Reflex Crit. 2019 Jul 15;32(1):14. doi: 10.1186/s41155-019-0127-2.

Miguel AQC, Madruga CS, Cogo-Moreira H, Yamauchi R, Simoes V, Ribeiro A, da Silva CJ, Fruci A, McDonell M, McPherson S, Roll JM, Laranjeira RR. Contingency management targeting abstinence is effective in reducing depressive and anxiety symptoms among crack cocaine-dependent individuals. Exp Clin Psychopharmacol. 2017 Dec;25(6):466-472. doi: 10.1037/pha0000147.