Treatments for substance abuse - TDMaddox

http://informahealthcare.com/dep ISSN: 0968-7637 (print), 1465-3370 (electronic)

Drugs Educ Prev Pol, 2016; 23(5): 404–409 ! 2016 Informa UK Limited, trading as Taylor & Francis Group. DOI: 10.3109/09687637.2016.1153603

Effectiveness of formalised therapy for adolescents with cannabis dependence: A randomised trial

M. Lascaux1, S. Ionescu2, and O. Phan3

1University Paris 8, Laboratory of Psychopathology and Neuropsychology, Pierre Nicole Center – Croix rouge, Paris, France, 2Professor Emeritus of

Psycholopathology, University Paris 8, France and University of Québec at Trois-Rivières, Trois-Rivières, Canada, and 3Inserm Unit 1178, Addiction

Unit Dupré Clinic, Fondation Santé des Etudiants, Sceaux, France

Abstract

Aims: During the past 20 years, cannabis consumption among adolescents has dramatically increased. In France, over 300 outpatient treatment centres caring for youngsters with cannabis abuse diagnoses were created. For this study, five European countries participated in a randomised controlled trial on adolescents with cannabis addiction. The goal was to compare a Multidimensional Family Therapy (MDFT) to what was usually done in these five countries (‘‘Treatment As Usual (TAU)’’). In France, clinical practices are heterogeneous; therefore, the French TAU had to be formalised. French researchers compared MDFT to a formalised TAU and non-formalised one. The aim of this article is to present the interest of formalising therapeutic French practices. Methods: The efficacy of formalised versus unformalised therapy was assessed using two criteria: decrease of cannabis use over a one-year period measured by Adolescent Diagnostic Interview-light (ADI-light) and by Time Line Follow BACK (TLFB). Findings: Results show that the formalised therapy is more effective in preventing cannabis abuse than non- formalised therapy. At 12 months, this difference is statistically significant (TLFB: p50.05). Conclusion: The formalisation of explicit TAU has strengthened the therapist’s involvement in the therapeutic process. This study presents experimental results which demonstrate that formalisation and supervision increased therapeutic efficacy in the treatment of adolescents suffering from cannabis abuse or dependence.

Keywords

Cannabis, adolescent-psychotherapy, psycho- therapy-comparative studies

History

Received 29 September 2015 Revised 31 January 2016 Accepted 3 February 2016 Published online 17 March 2016

Introduction

Over the past 15 years, epidemiological studies have shown a

steady increase in cannabis consumption among French

adolescents (Beck, Guignerd, & Richard, 2011; Spilka & Le

Nézet, 2012). Currently, France has the highest cannabis use

in Europe (Hibbel et al., 2012). At the same time, the number

of people seeking treatment for cannabis abuse increased

dramatically (Obradovic, 2009). In 2005, specialised care

centres known as CJC for Consultations Jeunes

Consommateurs (Young Consumers Consultations) were

created to treat young drug users. International studies,

mainly conducted in the United States, have demonstrated the

effectiveness of therapies based on motivational interviews,

cognitive behavioural therapy and the family approach

(Dennis et al., 2002). In particular, the Multidimensional

Family Therapy (MDFT) method, developed by Professor

Liddle’s team in Miami found reduced cannabis consumption

in young adolescents with cannabis addiction and enhanced

compliance in treatment (Liddle, 2001; Liddle et al., 2001).

Therefore, five European countries decided to build a

randomised clinical trial (RCT) comparing MDFT to

treatments commonly used; the project was named

International Cannabis Need of Treatment (INCANT) (Phan,

Bonnaire, Bastard, & Jouanne, 2008; Rigter et al., 2010). For

research purpose, usual treatments were formally described

and termed Treatment As Usual (TAU) (Lascaux, Couteron, &

Phan, 2012). In France, clinical practices are usually hetero-

geneous and not formalised. Therefore, two types of TAU were

included in the INCANT study: an unformalised TAU to

encompass usual practices and an explicit formalised TAU

(TAUe) for research purposes (Lascaux, Bastard, Bonnaire,

Couteron, & Phan, 2010). The aim of this article is to compare

the efficacy of TAUe versus TAU on cannabis abuse in

adolescents in order to evaluate the interest of formalisation.

Description of two models: TAU and TAUe

TAU

In France, usual clinical practices are not formalised and are

based on the particular psychotherapeutic affiliation of the

therapist (psychoanalytic, systemic or cognitive behavioural

therapy). Each TAU therapist had to describe therapeutic

processes for study including frequency of sessions, duration

of therapy and therapeutic techniques.

The TAUs in the INCANT study were delivered by pairs of

TAU therapists (psychiatrist and a psychologist). None of the

TAU therapists was supervised.

Correspondence: M. Lascaux, PhD, University Paris 8, Laboratory of Psychopathology and Neuropsychology, Pierre Nicole Center – Croix rouge, 54 rue de l’Amiral Roussin, 75015 Paris, France. E-mail: [email protected]

The therapeutic process of TAUs was not pre-defined.

Both therapists applied the psychotherapeutic approaches

with which they were most familiar and could integrate others

models like the motivational interviewing (MI): the psych-

iatrist with a systemic background included parents to work

on family interactions; the psychologist with a psychoanalyt-

ical background focused exclusively on the subjectivity of the

adolescent.

TAUe

The TAUe was based on the interview of 10 French therapists

who were practicing in the specific centres for adolescents

and drug abuse (Consultation Jeunes Consommateurs)

(Lascaux et al., 2010). The French research team analyzed

the interviews and suggested the application of the TAUe as a

formalised therapy.

As in the TAU model described above, the TAUe

treatments were applied by pairs of therapists consisting of

a psychiatrist and a psychologist.

The characteristics of the TAUe were as follows:

– adolescents were seen in therapy once a week during six

months;

– parents were systematically met at the first interview in

order to assess their view of the situation. During the

follow up, the therapist kept them informed on the

clinical situation of their child;

– the TAUe therapist was individually supervised once a

week to improve his efficiency and to ensure adherence

to the therapeutic model;

– there was no TAUe manual, but TAUe supervisor and

therapists could refer to the formalised therapy – TAUe.

TAUe is an integrative therapy, focused on the adolescent

and his addictive behaviour. The main therapeutic approaches

used in this study included:

– MI to enhance the process of change with adolescents

(Miller & Rollnick, 2002);

– an experiential approach which focuses on first experi-

ences of drug use in adolescents (Couteron, 2001;

Therrien, 2006);

– a cognitive approach with the functional analysis of drug use

and a focus on the internal and external factors that trigger

the consumption (Beck, Rush, Shaw, & Emery, 1979);

– a psycho-dynamic approach which improves insight in

the adolescent and helps to verbalize concerns (Hachet,

2005; Jeammet & Bochereau, 2007).

The course of therapy follows a therapeutic process in

three phases. Figure 1 describes the therapeutic process.

Methodology

Research centres and teams

This study was conducted in two centres:

– the Emergence Center (EET), attached to the Montsouris

Mutualiste Institute in Paris. The Emergence team was

composed of a researcher, a TAUe therapist, a TAU

therapist and a MDFT therapist. All were located in the

EET in the 13th district of Paris;

– the Center of Assistance for Drug Addicts (CEDAT),

attached to Mignot Hospital in Versailles.

The team was composed as above of a researcher, a TAUe

therapist, a TAU therapist and a MDFT therapist. All were

working for the CEDAT, however the TAUe and MDFT

therapists were located in Mantes-la-Jolie site and the TAU

therapist in the Saint Germain-en-Laye one.

Sample

To build the sample in accordance with the objectives of our

research, the inclusion and exclusion criteria defined in a

previous study (Phan et al., 2011) were applied as described

in Table 1. Our sample consists of 73 adolescents.

This article only focuses on the TAU and TAUe treatments.

The treatment (TAU and TAUe) was randomly assigned to

each adolescent (‘‘Urn Randomisation’’). Except in the Saint-

Germain-en-Laye center, adolescents were only included in

the TAU treatment. Despite this methodological bias, the

adolescents of Saint-Germain-en-Laye center were included

in our sample in so far as they had similar sociodemographic

characteristics than other adolescents included (from the

baseline). The sample distribution is presented in Table 2.

Although the sample size is small, we compared two groups

of youngsters treated (all randomised n¼73): one group composed of adolescents included in the TAUe (n¼38) and another one included in the TAU (n¼35). Baseline analysis indicates that 90% of teens were referred in consultation by

their parents or supportive school professionals (Phan et al.,

2011). Others were referred by the courts (65 vs 8). Free,

informed and written consent from both adolescent and

parents was mandatory.

The sociodemographics characteristics of our sample

appear to be very homogeneous and the data is 99% complete.

The average age of the patients is 16.3 years with a standard

error of 1.2. There is a high prevalence of boys: about 85% vs

15% girls. Almost all adolescents live in the parental home

(98%) and are from medium or higher socio-economic

background. Two-thirds of families are of French origin and

a third of foreign origin (North Africa). In half the cases, the

families had not mental or addictive disorders or legal

problems. Ninety percent of adolescents attend school: 65%

are enrolled in a high school and 25% in a vocational school.

Therapeu�c Alliance and Assessment Empathic listening

Reformula�on of the demand

Strenghtening changes Coping strategies

Balance sheet of therapy

Work focuses on the underlying problem Psychotherapeu�c

engagement

Support the self-assessment of consump�on management Effects/Consequences

Change Process Disorders associated

Stage 1 1 Month

Stage 2 4 Months

Figure 1. TAUe therapeutic process.

DOI: 10.3109/09687637.2016.1153603 Effectiveness of formalised therapy 405

Over half of the sample have had minor problems with the law

(have been re-arrested or put in police custody).

Research instruments

A battery of tests was applied at baseline, then at three, six,

nine and 12 months. To assess the level of cannabis addiction,

we chose two scales commonly used in the field of addiction

research:

– Adolescent Diagnostic Interview-Light (ADI-Light)

(Winters & Henly, 1993), which identifies drug use

disorders according to diagnostic criteria established in

the DSM-IV. This scale has good psychometric proper-

ties (test–retest reliability 0.82; inter-rater agreement

0.78) (Winters, Stinchfield, Fulkerson, & Henly, 1993;

Winters, 2000);

– Time Line Follow Back (TLFB) (Bry & Krinsley, 1992;

Sobell & Sobell, 1992; Robinson, Sobell, Sobell, & Leo,

2014), which measures the number of days of cannabis use

among adolescents during the 90 days preceding the

assessment (Waldron et al., 2001). It has good psychomet-

ric properties (test–retest reliability ranged from 0.31 to

0.86 and internal consistency was 0.93) (Levy et al., 2004).

– The personal and environment risk factors of cannabis

addiction were assessed by the Youth Self Report (YSR)

and the Child Behavioral CheckList (CBCL) (Achenbach

& Edelbrock, 1983) from the Achenbach System of

Empirically Based Assessment; and by the Family

Environment Scale (FES) (Moos & Moos, 1986).

– The Satisfaction Scale (SS) (Brannan, Sonnichsen, &

Heflinger, 1996) assessed the adolescent’s and parents’

satisfaction of the therapy.

Conduct of research

In the context of the INCANT RCT, the evaluation was con-

ducted in several stages in parallel as presented in Figure 2.

Processing data

Processing data was performed using the Statistical Package

for the Social Sciences (SPSS 17.00; Inserm Unit U1178,

Paris, France). Results are presented in terms of percentage,

mean and standard error. The analysis of variance was

calculated using the Fischer–Snedecor test. Statistical signifi-

cance for establishing differences between both therapies was

set at 5% (p¼0.05).

Analysis of findings

ADI-Light

Data presented in Figure 3 show the diagnostic cannabis use of

adolescents at each assessment over one year, according to the

ADI-Light. At baseline (T0) 80% of adolescents were

diagnosed as cannabis dependents and only 20% as cannabis

abusers. At 12 months (T12), TAUe led to a 55% decrease in

cannabis dependence against 40% for TAU. In addition, the

number of adolescents falling in the ‘‘no diagnosis’’ category

was higher in TAUe (Ntaue¼9) than in TAU (Ntau¼6), whereas in the initial assessment, the percentage of dependents

was more important in TAUe than in TAU (refer to the arrows

on the graph). This graph highlights the fact that the decrease of

cannabis use occurs in stages: dependents become abusers and

abusers become ‘‘no diagnosis’’. However, this reduction is

stronger in adolescents followed with TAUe than with TAU.

TLFB

Diagnostic criteria for abuse and dependence (DSM-IV-TR)

are easily assigned to adolescents. The TLFB provides a more

detailed view of cannabis use and its evolution during one

year. Both scales are complementary. Data collected on TLFB

scale are shown in Table 3 and plotted in Figure 4.

From the analysis of Figure 4, at baseline (T0), the average

cannabis consumption by adolescents over 90 days is 63 days,

representing almost daily use. Concerning the evolution of the

frequency of cannabis use over a one-year period, we

observed a significant decrease in the first six months (T6)

corresponding to the duration of the therapy, followed by a

slight increase from months six to nine (T9) (three months

after the end of therapy) and a decrease thereafter until month

12 (T12) that shows the durability of the reduction. However,

the decrease is greater in adolescents followed in TAUe than

those followed in TAU. This difference between the TAU and

TAUe is significant at six months (T6¼4853 F (1, 58) p¼0.032) and 12 months (T12¼6194 F (1, 59) p¼0.016) in favour of TAUe.

Therefore, while the two therapies produce a decline in

cannabis addiction, the TAUe is more effective than TAU at

12 months.

In addition, other data from the ADI-light scale on other

substances confirm that adolescents did not offset the

decrease in their cannabis use by consuming another drug.

Furthermore, the results of Achenback scales on internalised

Table 1. Criteria for inclusion and exclusion of research.

Criteria for inclusion Criteria for exclusion

– Adolescents consultants in one of the centre; – aged between 13 and 18 year; – with a diagnosis of cannabis abuse or dependent, according

to the DSM-IV-TR; – with at least one parent accepting to participate in therapy and study

– refusal to participate; – the inclusion of adolescent in other study; – adolescent and parents don’t speak French; – the adolescent in a psychiatric acute crises requiring hospitalisation

Table 2. Distributions of inclusions according to the centre.

Centre TAU TAUe

CEDAT 12 11 Emergence 23 27 TOTAL 35 38

73

406 M. Lascaux et al. Drugs Educ Prev Pol, 2016; 23(5): 404–409

and externalised problems, report a decrease in pain symp-

toms and, by the same time, a decrease of cannabis use. This

suggests that the formalisation of therapy (TAUe) enhances its

efficacy in treating cannabis addiction.

We are aware that some limitations in our study may have

had an influence on data collection, such as randomisation

error on one of the centres and the difference in the basic

training of therapists (psychiatrist and psychologist).

Discussion

Data from the ‘‘drug treatment’’ literature support the fact

that cannabis addiction among adolescents cannot be easily

resolved without treatment (Rigter, 2006). According to a

German study, in six out of 10 cases, cannabis abuse or

dependence still exists after five years without treatment (Von

Sydow, Lieb, Pfister, Hoffler, & Wittchen, 2002). So treating

cannabis abuse and dependence is crucial. The aim of the

TAUe therapy is to reduce cannabis use and adolescence

psychological pain.

Results from our study support the case for treatment.

Moreover, results from our small sample indicate a better

efficacy of the TAUe compared to the TAU on reducing

cannabis use at T6 (end of therapy) and at T12 (showing the

durability of the reduction). At T9 (three months after the end

of therapy), our results show a slight increase of cannabis

consumption. How can the efficacy difference between TAU

and TAUe be explained? The formalisation and supervision of

the TAUe have most probably strengthened the therapist’s

involvement. Therapy efficacy cannot be attributed solely to

formalisation and supervision. Ablon and Jones (2002)

revealed that adherence to the model on the part of the

therapist was a key component of therapeutic success.

Although supervision enhances therapist’s skills, few studies

directly focus on the relationship between therapist

Figure 3. Diagnostic of cannabis use at T0 et T12 (Adolescent Diagnostic Interview-light).

Figure 2. Conduct of research.

Inclusion + Urn Randomisa�on

TAU TAUe

End of study par�cipa�on

T0 = Intake interview, ADI-light, TLFB

T6 month = TLFB

T3 month = TLFB

STAGES ASSESSMENT

T9 month = TLFB

T12 month = ADI-light, TLFB

End of therapy

Table 3. Average number of days of cannabis use for each quarter of a year, by therapy (TLFB).

Assessment T0 T3 T6 T9 T12

TAU Mean 64 52 47 50 47 N 35 28 27 29 27 SE 26 29 29 31 27

TAUe Mean 62 41 31 36 30 N 38 36 33 34 34 SE 28 31 28 31 27

Total Mean 63 46 38 43 37 N 73 64 60 63 61 SE 27 30 29 31 28

There is a greater data loss in TAU with TAU than with TAUe. SE, Standard Error.

DOI: 10.3109/09687637.2016.1153603 Effectiveness of formalised therapy 407

performance, client changes and supervision (Holloway &

Neufeldt, 1995). A team of Australian researchers have

evaluated the effectiveness of clinical supervision for health

professionals; however, the emphasis was on improving

clinical supervision processes (Dawson, Philips, & Leggat,

2012). Those findings promote praxeological research which is

based on the fact that action precedes knowledge. Indeed,

praxeology is defined as ‘‘a structured approach which aims at

making the action more conscious, more independent and

effective’’ (St Arnaud, 1995). This approach contributes to

reconciling clinical practices and research. Qualitative ana-

lyzes performed in this study highlighted the importance of

formalisation of therapeutic alliance construction with the

adolescent. Therefore, formalisation and supervision would

increase the effectiveness of therapy. Treatment intensity and

formalisation are not independent variables. Seeing adoles-

cents intensively needs to have something to say to them. Too

many ‘‘how was the week’’ sessions would alter the thera-

peutic alliance and jeopardize treatment retention. The

formalisation of empirical therapy improves our clinical

practices.

According to Kazdin (2004), building a therapeutic model

implies the following steps:

– to differentiate the therapy from existing therapeutic

approaches and from clinical experience of professionals

in the field;

– to assess the efficacy of the model on the target symptom

and the related disorders;

– to analyze the mechanisms of change in the therapeutical

process (with supervision, videotape, etc.);

– to improve the model and define the therapeutic

indications;

– to evaluate the possibilities of generalising this therapy.

Conclusion

The primary objective of this study is to report the effect of

applying a formalised versus a non-formalised therapy on

adolescents with cannabis addiction. Despite some methodo-

logical bias and a small sample, statistical analyzes demon-

strates the superiority of the TAUe model compared to the

TAU model on the evolution of cannabis addiction (at year 1).

Supervision of TAUe therapists has strongly contributed to

treatment efficacy by strengthening the involvement of

therapists.

In addition, this study contributes to the assessment of

psychotherapy in the field of addiction in France and to the

development of clinical practice in the treatment of adolescent

with cannabis abuse.

However, additional qualitative analyzes are needed to

complete this study in order to identify mechanisms of

change. Defining parental involvement in this therapy is also

interesting because they represent a key success factor.

The creation of a therapeutic model for a specific

population requires two processes:

– a ‘‘top-down’’ process which consist of formalising a

therapy based on a literature review, a theoretical

conceptualisations and therapist’s clinical experiences;

– an empirical ‘‘bottom-up’’ approach which aim at

analyzing clinical practices from real situations to

improve and build relevant theoretical formalisations.

Indeed, this formalisation and assessment work led to a

therapeutic manual: the PAACT (The Coaching and

Therapeutic Process to build Alliance and Changes)

(Lascaux, Couteron, & Phan, 2014). This writing of the

manual, and its dissemination among professional was

ordered by the MILDECA (Inter Ministerial Department for

Drug and Addiction).

Declaration of interest

We declare that there are no conflicts of interest.

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