15 Treatment for stimulants
Guidelines for treatment improvement
NAC, Kings College London
EUROPEAN COMMISSION HEALTH & CONSUMER PROTECTION DIRECTORATE-GENERAL Directorate C -Public Health and Risk Assessment
The content of this report does not necessarily reflect the opinion of the European Commission. Neither the Commission nor anyone acting on its behalf shall be liable for any use made of the information in this publication.
2 Aims and objectives
2. Research evidence base.
2.1 Treatment environment and holistic treatment and care
2.2 Effectiveness by treatment setting
2.3 Prescribing for stimulant problems
2.4 Psychosocial Interventions
3.1 Access to care
3.2 Pathways of care
Stimulant users include users of powder cocaine, crack cocaine and amphetamines. At present there is not a complete treatment package that has been demonstrated to achieve abstinence and prevent relapse for stimulant users. Consequently treatment for stimulant users should include an initial phase of seeking the cessation of stimulant use, a second phase involving relapse prevention and a third phase that seeks to maintain abstinence through the learning of new skills to achieve this. However stimulant users, like other problem drug users, may experience a range of medical problems or emergencies, psychiatric problems or crises or various social, legal or employment problems which may need the involvement of a range of services beyond drug treatment services (SAMHSA, 1999; NTA, 2002).
1.2 Philosophy and approach
Concerted strategies are required to attract stimulant users into treatment where, unlike opioid treatment, there is no pharmacological treatment such as methadone or buprenorphine they can benefit from. Rapid intake into treatment is required to make the most of high motivation to enter into treatment. Concerted strategies are also required to retain patients in treatment (NTA, 2002).
1.3 Relevance of the problem
Estimates of the extent of problem cocaine use in Europe are available for only three countries, Italy, Spain and the United Kingdom. Here the estimates from these countries are between three and six problem users of cocaine users per 1,000 adults aged 15-64 (EMCDDA, 2008).
Using its Treatment Demand Indicator data the EMCDDA has recorded cocaine as a secondary problem drug for around 15% of all outpatient clients. Most countries in Europe report a low proportion of cocaine users among all clients in drug treatment, although the Netherlands and Spain have reported high proportions of 35% and 42% respectively in 2004 (EMCDDA, 2008).
2 Aims and objectives
2.1 Aims of treatment for stimulants
Treatment for stimulant users aims to achieve cessation of stimulant use, prevent relapse and maintain abstinence through the learning of new skills to achieve this. Programmes to treat stimulant misuse should include the following:
• An assessment of the psychological, psychiatric, social and physical status of patients using defined assessment schedules
• An assessment of the degree of misuse and/or dependence on relevant classes of drugs, notably opioids, stimulants, alcohol and benzodiazepines
• To define a programme of care and to develop a care plan to carry out a risk assessment
• To prescribe medication safely and effectively to achieve withdrawal from psychoactive drugs
• To identify risk behaviours and offer appropriate counselling to minimise harm
• To assess the longer-term treatment needs of patients and provide an appropriate discharge care plan
• To assess and refer patients to other treatments as appropriate
• To monitor and evaluate the efficacy and effectiveness of prescribing interventions
• To provide referral to other services as appropriate (NTA, 2002)
Client groups served
Could not find anything to make an evidence-based statement.
Those who have made an informed and appropriate decision to seek help for their stimulant misuse problems should be eligible for treatment.
Could not find anything to make an evidence-based statement
Could not find anything to make an evidence-based statement
2. Research evidence base.
2.1 Treatment environment and holistic treatment and care
2.2 Effectiveness by treatment setting
Patients with a cocaine or other stimulant use problem generally do not require treatment in an inpatient setting as withdrawal syndromes are not severe or medically complex (Kleber et al, 2006). The limited evidence available suggests that most patients can be effectively treated in intensive outpatient programmes. For example, in a study comparing outcomes for dependent crack users when randomly assigned to residential or day drug abuse treatment, relapse outcomes showed that at 12-18 month follow-up outcomes had converged and about half of both groups had remained abstinent (Greenwood et al, 2001). Those people with more severe polydrug and social or psychological problems found residential care more beneficial than less intensive or shorter interventions if they stayed there for at least three months (Simpson et al, 1999).
116 patients telephoning an outpatient cocaine treatment clinic were randomly assigned to intake appointments scheduled at four times: the same day, 1 day, 3 days or 7 days later. Significantly more subjects scheduled 1 day later attended their intake appointments and those offered intake appointments approximately 24 hours following their initial contact are more than four times as likely to attend their intake appointments as those scheduled later (Festinger et al, 2002). A study of patients participating in a cocaine treatment study found that minority and unemployed patients and those with more days of cocaine use were less likely to attend the intake appointment usually offered in 24 hours after telephone screening (Siqueland et al, 2002).
2.3 Prescribing for stimulant problems
Pharmacological approaches have been trialled for the treatment of the symptoms of cocaine intoxication, cocaine-related psychosis, the symptoms of acute withdrawal and the maintenance of abstinence over 3-6 months. Although cocaine users do not face physical withdrawal symptoms, during abstinence subjects may experience symptoms such as depression, fatigue, irritability, anorexia and sleep disturbances. Antidepressants (notably desipramine and fluoxetine), dopamine agonists (notably amantamide, bromocriptine and pergolide, and anticonvulsants (notably carbamazepine and phenytoin) and mood stabilisers (notably lithium) have been trialled for the treatment of cocaine dependence and there is no evidence to support their effectiveness (Lima et al, 2002). A range of medications, including modafinil, are currently being trialled (Vocci & Elkashef, 2005).
Cocaine and alcohol are often used in combination and it is difficult for the individual to cease use of only one substance. Disulfiram (Antabuse), used in the treatment of alcohol dependence, has been found to reduce cocaine use indirectly through its effect on alcohol use (Carroll et al 2000). Its use in combination with psychosocial approaches has been found to have an impact on treatment retention and levels of cocaine use, although this effect had faded at one year follow-up in one study . (Carroll et al 2000; 2004). Disulfiram has also been found to reduce cocaine use among patients being treated for opioid addiction (Petrakis et al 2000; George et al 2000).
There is no evidence to support the use of maintenance therapy for stimulant users (UK. Department of Health, 2007). A recent meta-analysis of studies using CNS stimulants for the treatment of cocaine dependence found that CNS stimulants did not decrease dropout rate, cocaine use or craving compared to placebo (Castells et al, 2007). Studies have shown that providing methadone or buprenorphine maintenance therapies for those with opiate dependence problems but also use cocaine, can lead to reductions in cocaine use, an effect enhanced when used in combination with contingency management techniques or disulfiram (Jofre-Benet, 2004; Schottenfeld et al, 2005).
2.4 Psychosocial Interventions
Psychosocial interventions that have been examined for stimulant misuse include:
• Contingency management
• Cognitive Behavioural Therapy
• Skills training
• Relapse prevention
• Cue exposure
• Motivational Interviewing
• Counselling approaches
Contingency management (CM) and reinforcement approaches seek to provide immediate rewards for negative drug tests, with the aim of increasing treatment retention and improving outcomes, with instant loss of reward for recurrent drug use. A review of the evidence on contingency management concluded that the approach is acceptable to patients, contributes to patient retention and is effective in achieving initial abstinence (Van Horn and Frank, 1998). A number of controlled trials identified reinforcement techniques leading to positive outcomes. For example, Higgins et al 1993 reported on 38 cocaine dependent patients and found that, compared with standard drug abuse counselling, 12-week outpatient behavioural treatment led to greater treatment acceptance, longer continuous cocaine abstinence and better retention rates. Continuous cocaine abstinence was improved when a voucher reward system was added to behavioural therapy, with 50% for those receiving the vouchers compared to 10% of those who did not. Treatment retention was improved with 93% of those receiving vouchers retained against 67% of those not receiving vouchers. Other randomised trials have demonstrated similar higher rates of treatment retention and continuous cocaine abstinence (Higgins et al 1994; Silverman et 1996; Petry et al, 2004; 2006). A study of cocaine using methadone patients found that the combination of a high value reinforcer of $100 combined with a low response requirement of 2 days of abstinence (defined as a 50% or greater reduction in cocaine use over the 2 days) resulted in an abstinence rate of 80% of the patients (Robles et al, 2000). This finding was replicated in a subsequent study where continuing reinforcement conditions led to sustained abstinence, although abstinence rates declined over the 11-day period of the intervention (Katz et al, 2002). A controlled trial reported positive outcomes when housing was provided as an incentive for abstinence for homeless people using cocaine (Milby et al 2000). Combined with group therapy in methadone clinic, the prize-based CM patients had more cocaine-negative urine samples and attended more group sessions than the control group receiving treatment as usual (Petry et al, 2005). Studies have also found both short-and long-term voucher-based reinforcement for cocaine users in methadone maintenance patient samples are effective in decreasing cocaine use (Sigmon et al., 2004; Silverman et al., 2004).
Psychotherapeutic interventions including Cognitive Behavioural Therapy
The results of studies of cognitive-behavioural therapies (CBT) with cocaine dependence are inconsistent. Whilst one study found better long-term outcomes for CBT than clinical management (Carroll et al, 1994), two further studies found no long-or short-term effects (Carroll et al, 1991, Wells et al, 1994). CBT has been found to be differentially effective for participants in studies with a history of depression (Carroll et al, 1994; Maude-Griffin et al, 1998). One study compared professionally delivered psychotherapy with structured counselling in 487 randomly assigned patients. Patients in the sample receiving combined group and individual counselling had better treatment outcomes than those receiving psychotherapy, who had similar outcomes to those patients receiving group counselling treatment (Crits-Cristoph et al, 1999). Using the data from the same study, the investigators found that there were no significant differences on measures of psychiatric symptoms, employment, medical, legal, family-social, interpersonal or alcohol use problems (Crits-Cristoph et al, 2001). A study of combined psychotherapies randomly assigned 184 individuals to 4-month standard or intensive group therapy and within these groups, either received no additional services, individual therapy or individual plus family therapy. There were no differences in retention or 12-month follow-up cocaine use outcome for the different treatment modalities or intensities (Hoffman et al 1996). A recent RCT on brief cognitive behavioural interventions for amphetamine users found that the number of treatment sessions had a significant effect on the level of depression, and also abstinence rates were better in those attending at least twice or more (Baker et al., 2005).
Relapse prevention and skills training
Several studies have failed to demonstrate greater efficacy of skills training or relapse prevention over control approaches (Hawkins et al 1986; 1989; Carroll et al 1991;1994). The studies conducted by Carroll et al found that patients with more severe cocaine use at baseline did better with relapse prevention than other control approaches including clinical management and interpersonal therapy. Whilst a study comparing the effectiveness of relapse prevention approaches and standard group counselling found neither approach similar to the other in an initial study while a two-year follow-up found that those receiving relapse prevention had better outcomes over the longer term. A study of 32 cocaine dependent outpatients found that group delivery of relapse prevention therapy was significantly more effective than individual therapy in the immediate post-treatment period in reducing cocaine use and cocaine-related problems (Schmitz et al, 1997). Monti et al (1997) compared coping skills training (CST) tailored to specific high risk situations of cocaine users with a control approach using manualised meditation and relaxation training. Those patients with CST in addition to their treatment programme experienced shorter and less severe relapses.
Comparisons of psychosocial approaches
CBT and Contingency Management
CBT and 12-step
A study of 128 crack using patients comparing the efficacy of cognitive behaviour therapy (CBT) with 12-step facilitation found that those treated with CBT were more likely to achieve abstinence than those in 12-step. The findings also provided support for matching hypothesis. The authors conclude that CBT is the better choice between the two when patient characteristics are unknown but that both approaches may be effective if more is known about the patient (Maude-Griffin et al , 1998).
Relapse prevention and 12-step
A comparison of a relapse prevention approach with 12-step both delivered in an outpatient setting found no difference in outcomes. However, the study found significantly better maintenance of reductions in alcohol use in the relapse prevention group, treatment completion was beneficial and produced better treatment outcomes (Wells et al 1994).
A study of cocaine abusers in a private substance abuse/partial hospital programme randomized patients to a motivational interviewing or meditation/relaxation control conditions before they received group sessions on cocaine specific coping skills training or educational discussions. Although the MI did not alter cocaine treatment outcomes, the MI had a differential effect according to baseline level of motivation or ambivalence. Those MI patients with more ambivalence or less motivation for change had fewer cocaine using days at follow-up. Motivational interviewing also improved treatment retention (Rohsenow et al, 1998). Similar findings were reported in a pilot study of patients assigned a MI or a detoxification-only condition. Although participants completed the detoxification programme at equal rates, completers who only received MI increased use of behavioural coping strategies and had fewer cocaine -positive urine samples on beginning the primary treatment programme. Those who had lower initial motivation were more likely to complete detoxification (Stotts et al, 2001). In contrast, more recent studies using brief MI sessions in a treatment population found no differences in the intervention group and the standard treatment group in days abstinent form stimulant drug use suggesting that those in these studies any already have been motivated to change their drug use and consequently did not require an additional motivational intervention (Miller et al, 2003; Rohsenow, 2004; Carroll et al, 2006; Mitcheson et al, 2007). In a small pilot study, cocaine-dependent patients with depression and stabilized with antidepressant were more likely to remain in treatment, complete the programme and have fewer psychiatric rehospitalizations and days in the hospital after MI treatment compared to a group receiving standard treatment (Daley et al, 1998). In a small study comparing amphetamine users receiving MI plus skills training with a control group receiving just a self help booklet, those receiving the intervention were more likely to become abstinent or show greater reductions in drug use, although there was a significant reduction in amphetamine use across the study group as whole (Baker et al, 2001). A later study that replicated and extended the trial with a larger sample reported that abstinence rates were slightly improved by the intervention and that there was a significant increase in the rates of abstinence for those who received two or more treatment sessions (Baker et al, 2005).
Brief interventions are usually interventions with a maximum of two sessions with the aim of encouraging change in terms of abstinence or the reduction of harmful behaviours associated with drug use (NICE, 2008). A large US RCT with a diverse sample of out-of –treatment cocaine and heroin users tested a brief intervention conducted by peer educations against screening and written advice and referral. Those receiving the intervention achieved slightly higher abstinence rates than the controls and at 6 month follow-up those receiving the intervention had achieved greater reductions in their cocaine use despite a lack of contact with treatment services (Bernstein et al, 2005).
3.1 Access to care
Access to the service
Treatment should be a readily available option for people who have a stimulant problem and have expressed an informed and appropriate choice to seek help (NICE, 2007). Information should be made available on criteria for access to the treatment programme. The material should describe who the service is intended for and what are the expected waiting times for entry (National Treatment Agency, 2002).. Services should respond quickly and positively to initial telephone enquiries and schedule appointments with minimal delay (SAMHSA, 1999)
3.2 Pathways of care
The majority of stimulant users are likely to be seen in an out-patient setting, while crisis management services may be needed for some users with an acute crisis (SAMHSA, 1999; NTA, 2002). Patients with multiple needs are more likely to benefit from intensive residential rehabilitation which can be provided on a day-care basis (NTA, 2002).
The limited data available and clinical experience suggest that treatment programmes of 12-24 weeks in duration are commonly used for treating stimulant misusers (SAMHSA, 1999). The US Drug Abuse Treatment Outcome Study (DATOS) found that the benefits of treatment among those in residential therapeutic communities were concentrated among those who had stayed for at least three months (Simpson,1999).
Staff involved in treating stimulant users should include nursing and medical staff, social workers and care managers, psychologists and counsellors. Staff should be trained in crisis management, specific counselling techniques and trained in mental health issues (NTA, 2002).
Those presenting for problematic stimulant use should be assessed to establish the presence and severity of stimulant use, as well as misuse of and/or dependence on other substances including alcohol. Assessment should be brief and focussed to avoid becoming a barrier to treatment for stimulant users who want quick access to treatment (SAMHSA, 1999).
Assessment should include
• Urinalysis to aid confirmation of the use of stimulants and other drug use
• The taking of a history of drug and alcohol use and previous treatment episodes
• A review of current and previous physical and mental health problems
• Risk assessment for self-harm
• An assessment of present social and personal circumstances
• A consideration of the impact of drug misuse on family members and any dependents
• Offer screening for hepatitis, HIV and sexually transmitted infections
• Development of strategies to avoid risk of relapse (NICE, 2007).
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