Transcript Lecture 9: How much would it cost me to buy a day`s abstinence?

How much would it cost me to
buy a day’s abstinence?
Behaviour therapies in the addictions
John Marsden, Ph.D.
Division of Psychological Medicine & Psychiatry
National Addiction Centre,
King’s College London, UK
“Failure” Rates for Addictions
(reduction <50% in use after 6 mos.)
70
50
40
Alcohol
Opiates
45
Cocaine
O’Brien & McLellan, 1996, The Lancet
Nicotine
Comparative Rates for
Treatment Compliance & Relapse
% Complied w Trt Plan
% Relapsed (Mdn) in 1 Yr
70
55
50
40
30
Diabetes
Hypertension
30
Asthma
O’Brien & McLellan, 1996, The Lancet
Behavioural interventions
► Theoretical
foundations
► Laboratory and clinical foundations
► Reinforcement
…. a process wherein a stimulus event
increases the future probability of drug use by
acting as a consequence.
► Effective
interventions
► Combination therapies
► Key issues and future directions
Theoretical foundations
B.F. Skinner
► Three-term
contingency
• Discriminative stimulus
• Operant response
• Reinforcement (positive and negative)
► Behaviour
modified by consequences
► Schedules of reinforcement
► Drug self-adminstration at the core
► Drugs function as primary reinforcers
► Altering behavioural contingencies
Laboratory Foundations (1)
► Opiates,
psychostimulants, nicotine,
alcohol and cannabis serve as
reinforcers in a diverse range of species
► Behaviours aimed at obtaining drugs
exhibit strong motivational pressure
► Animal drug use can be modified by
manipulating variables that affect other
operant behaviours:
• Increasing number of responses required
• By blocking/eliminating the reinforcement
• By punishing the responses on which drug
reinforcement is contingent
Laboratory Foundations (2)
► Associative
learning and memory
processes underpin addiction
Treatment Protocol
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Weeks 1-12
• 2x weekly counseling
• 3x weekly urine testing
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Weeks 13-24
• 1x weekly counseling
• 2x weekly urine testing
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Months 7-12
• Aftercare – 1x monthly check-in with counsellor
• Random urine testing
Elements:
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Antabuse therapy (clinical punishment)
Relationship counseling & skills training
Occupational assistance
Vouchers for goods and services
Vouchers (weeks 1-12 only)
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Urine tests negative for benzoylecgoine (BE)
earned points worth $0.25.
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The first BE negative earns 10 pts @ $0.25
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Voucher for each subsequent consecutive
negative test increases by 5 pts.
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The equivalent of $10 bonus is earned for
every 3 consecutive negative tests.
Voucher protocol
BE-positive tests or failure to give a specimen
‘reset’ vouchers back to initial value.
► BE-positive tests or failure to give a specimen
reset vouchers back to initial value.
► 5 consecutive negative tests returned
vouchers back to the value preceding a reset.
► Vouchers were exchangeable for retail items
in community; max. earnings possible =
$997.50
► All purchases were made by staff and had to
be deemed by therapists to be recovery
appropriate.
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Higgins et al. (1994) Incentives Improve Outcome in
Outpatient Behavioral Treatment of Cocaine
Dependence. Arch. Gen. Psychiat, 51, 568-76
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40 patients randomlized to two groups
Treatment lasts for 25 weeks.
2x weekly counseling and 3x weekly urinalysis
in weeks 1-12; reduced to 1x weekly counseling
and 2x weekly urinalysis in weeks 13-24.
Counseling in both groups based on the
Community Reinforcement Approach (CRA).
Voucher group rewarded for BE-negative results
in weeks 1-12. During weeks 13-24, both groups
received only a single $1 lottery ticket for each
BE-negative test.
Higgins et al. (2000) Contingent Reinforcement
Increases Cocaine Abstinence During Outpatient
Treatment and 1 Year of Follow-up. JCCP,
2000, 68, 64-72
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70 patients randomized to two groups.
Treatment over 24 weeks and 1 year follow-up
All get CRA + vouchers
One group receives vouchers contingent on
cocaine abstinence
Other group receives vouchers non-contingently
(yoked control)
24 weeks treatment and 1 year of follow-up
Iguchi et al. (1997) Reinforcing operants other than
abstinence in drug abuse treatment. JCCP, 65, 425-
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103 MMT patients who completed 6 weeks of
baseline testing to one of three conditions:
(a) standard MMT
(b) MMT + up to $15/week in vouchers for
submitting drug-free urine samples
(c) MMT + up to $15/week in vouchers for
submitting treatment plan tasks
Interventions over 12 weeks
Follow-up over 6 months
TP Intervention
has greater time effect that other 2 treatmernts
% drug-free urine samples
40
35
TP
30
UA
25
20
SC
15
10
5
0
Baseline
Weeks 1–6
Intervention
Weeks 7–12
Intervention
Weeks 13–18
Follow-Up
Weeks 19–24
Epstein et al. (2003) Cognitive–Behavioral Therapy Plus
Contingency Management for Cocaine Use: Findings
During Treatment and Across 12-Month Follow-Up.
Psychol Addict Behav; 17, 73–82.
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193 MMT outpatients randomized tovoucher
availability (contingent or not contingent on
cocaine-negative urine testing.
Follow-ups at 3, 6 and 12 months
Patients abstinent from cocaine over 87 test days
Patients abstinent from cocaine over 87 test days
Patients abstinent from cocaine over 87 test days
A meta-analysis of voucherbased reinforcement therapy for
substance use disorders.
Jennifer Lussier et al. (2006)
Addiction, 101, 192-203
Methods
► Effect
sizes calculated for controlled studies
VBRT published between 1/91 & 3/04
► 65 studies reviewed, including 40 where
effects of contingent vouchers were
experimentally isolated
► Focus was on period when vouchers were
available
► Studies grouped by moderator variables:
type of drug targeted, control, duration of
VBRT, voucher $ value, voucher delivery
immediate or delayed, study setting
Experimental vs control conditions
► Results
as pearson correlation coefficient
where as a guide:
r = 0.10 (difference in effectiveness of 55% vs. 45%)
r = 0.30 (65% vs. 35%)
r = 0.50 ( 75% vs. 25%)
► 65
studies reviewed, including 40 where
effects of contingent vouchers were
experimentally isolated
► Studies grouped by moderator variables:
type of drug targeted, control, duration of
VBRT, voucher $ value, voucher delivery
immediate or delayed, study setting
Effects for different substances
Substance
cocaine
N
studies
12
Mean
weighted ES
0.35
opiates
3
0.39
cocaine & opiates
5
0.21
polydrug
6
0.20
cannabis
1
0.57
alcohol
1
0.32
nicotine
2
0.48
2x2 factorial design
Group 1
Group 2
Placebo
medication &
control VBRT
Active medication
& control VBRT
Group 3
Group 4
Placebo
medication &
active VBRT
Active medication
& active VBRT
Lambeth Harbour Study
► Randomised
controlled trial
► Voucher-CM only
► Synergistic voucher-CM + group based CBT
► 82 service users (primary cocaine)
► 8 week intervention
► 3 x weekly on-site, urine testing for cocaine
► 8 x 1.25 hr CBT with CM discussion focus
► All participants receive 8 x 1 hr keworking
► Follow-ups:
 At 1-month (week 12)
 At 3-months (week 24)
Outcome criteria
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(1) Immediate abstinence during weeks 7 & 8.
Participants must provide at least 2 cocaine negative urine
tests in each of weeks 7 and 8 and no positive tests.
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(2) Short-term abstinence no reported use of cocaine during
weeks 9-12 and provision of a negative urine test at the 12week (1-month) follow-up; and
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(3) Longer-term abstinence no reported use of cocaine during
weeks 21-24 and provision of a negative urine test at the 3month follow-up.
Statistical analysis by relative risk ratios for outcome criteria and NNT
Lambeth voucher-CM
► 24
tests on Monday, Wednesday & Friday
► Escalating schedule starting at £1
► Up by £0.5 for each successive –ive test
► Bonus for each series of 6 –ive tests
► Re-set following +ive test or DNA
► Return to previous level for 6 –ives (if time)
► Voucher for attending drop-in for 1.25 hours
► Final bonus for attending for all 24 tests
► Total voucher value possible = £323
► Harbour voucher credits exchanged for store
gift certificates as Argos, Footlocker, Woolworths etc.
The Harbour Steps
12
11
10
9
8
7
6
5
4
3
2
1
Week 1
Week 2
Week 3
Week 4
Week 5
Week 6
Week 7
Week 8
Lambeth CBT
► All
CBT attenders receive CM
► CBT has joint CM coaching and CBT skills
training purpose
► Key themes:
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Showing you the ropes
The CM rules!
Clearance reassurance
Personal voucher goals
Getting rolling
Brushing off a set-back
The crunch zone
Helping others
CBT skills
Key issues and future directions
Behavioural interventions using CM are
effective at encouraging initial abstinence.
► When contingencies removed effects taper off.
► However, they are rarely used in routine
treatment delivery settings and outside the
USA.
► They may be particularly effective when
combined/integrated with other interventions.
► Further development of reinforcement
schedules is needed: non-abstinent
reinforcement as initial step?
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