Identifying Ecological Momentary Intervention Targets:

Desire for Marijuana, Efforts to Avoid Use,and Episodes of Use

Lydia A. Shrier, MD, MPHDavid Williams, PhD

Division of Adolescent/Young Adult Medicineand the Clinical Research Center, Boston Children’s Hospital

Department of Pediatrics, Harvard Medical School

AcknowledgementsPamela J. Burke, PhD, RN, FNP, PNP and Amanda Rhoads, FNP

Disclosures

I have no conflicts of interest to disclose.

Ecological Momentary Interventions (EMIs)

Use mobile technology to deliver interventions in real time and in real life

Can be applied in moments leading up to potential substance use event, when substance desire and efforts to avoid use are occurring

Pilot Study of MOMENT InterventionTo reduce marijuana use among youth in primary

careMET (Motivational Enhancement Therapy): 2 sessions

EMI: 2 weeks of mobile reporting 4-6 times/day of

Marijuana desire Triggers for useEffort to avoid use Use

followed by responsive motivational messagesBaseline – Intervention – Follow-up at 3 months

Momentary assessments at each study phase 27 medical outpatients (70% F)

Age 15-24 years (M = 19.2)Used marijuana >3 times a week (Mdn = 6)

Initial Findings and New Questions

Desire to use marijuana and marijuana use declined over the study (Shrier, et al. 2014)

Why did marijuana use decrease?Was decreased desire related to decreased use?Did participants consciously try to avoid use?

If so, when and how?

MethodsAnalytic Sample: 1544 reports from 14 participants across 3 study phases (response rate 61%)

MeasuresDesire to use (0-9)Used marijuana (Y/N)Tried to avoid use (Y/N)If yes, what did you do?

15 strategies adapted from Coping Strategies Scale

MethodsAge- and sex-adjusted GEE models

Desire, Avoid, Use across study phasesDesire, Avoid Use

Tested for mediation and moderation of association between study phase and use

Explored specific strategies to avoid use

Changes in Use, Desire, and Effort to Avoid Use Before, During, and After MOMENT Intervention

Baseline Intervention Followup0

10

20

30

40

50

Use

% R

epor

ts

N = 518 N = 649 N = 377

* p < 0.05 in model adjusted for age and sex.

*

Changes in Use, Desire, and Effort to Avoid Use Before, During, and After MOMENT Intervention

Baseline Intervention Followup0

10

20

30

40

50

*Use

% R

epor

ts

3

2

1

0

Mean Desire

Desire

N = 518 N = 649 N = 377

* p < 0.05 in model adjusted for age and sex.

*

Changes in Use, Desire, and Effort to Avoid Use Before, During, and After MOMENT Intervention

Baseline Intervention Followup0

10

20

30

40

50

N = 518 N = 649 N = 377

Use

Desire

Avoid

* p < 0.05 in model adjusted for age and sex.

*

Mean Desire

3

2

1

0

% R

epor

ts

*

*

Desire and Effort to Avoid Use Independently Predicted Use

β Adjusted OR 95% CI p

Marijuana desire 0.12 1.13 1.07 – 1.19 <.0001

Effort to avoid use -1.53 0.22 0.11 – 0.44 <.0001

Adjusted for age, sex, and study phase.

Desire Partially Mediated Association Between Study Phase and Use

Model without Desire

β AOR p

Interventionvs. Baseline -0.13 0.88 0.48

Follow-upvs. Baseline -0.45 0.64 0.045

Adjusted for age and sex.

Desire Partially Mediated Association Between Study Phase and Use

Model without Desire Model with Desire

β AOR p β AOR p

Interventionvs. Baseline -0.13 0.88 0.48 -0.09 0.92 0.63

Follow-upvs. Baseline -0.45 0.64 0.045 -0.30 0.74 0.22

Adjusted for age and sex.

by 32%

by 33%

NS

Effort to Avoid Use Moderated Association Between Study Phase and Use

+ Effort to Avoid Use β Adjusted OR 95% CI p

Intervention vs. Baseline -1.75 0.17 0.05-0.64 0.008

Follow-up vs. Baseline -0.002 0.998 0.13-7.40 0.998

- Effort to Avoid Use β Adjusted OR 95% CI p

Intervention vs. Baseline 2.48 11.9 1.17-121 0.04

Follow-up vs. Baseline -1.42 0.24 0.004-14.5 0.50

Adjusted for age, sex, and desire.

Avoidance Strategies

7%

37%

26%

26%

4%

Avoided situation Distracted self Ignored urgeWaited it out Other N = 123

Avoidance Strategy and Probability of Use

Avoidance Strategy(vs. No Effort to Avoid) OR 95% CI p

Avoided situation 0.16 0.04-0.57 0.005

Distracted self 0.33 0.14-0.81 0.02

Waited it out 0.93 0.58-1.49 0.78

Ignored urge 2.27 1.22-4.25 0.01

Adjusted for age and sex.

Change in Avoidance Strategies

Baseline Intervention Follow-up0

10

20

30

40

50

60

70

Distracted selfIgnored urgeWaited it outAvoided situation

% R

epor

ts o

f Eff

ort t

o Av

oid

Conclusions

Desire and effort to avoid use both linked to use Desire partially mediated use following MOMENT

Focus on personal motivation + timely messagesMore “active” strategies to avoid use more effective?

Avoiding situation, distracting selfEfforts decreased & strategy type changed over study

Limitations

Small participant sampleSelf-report dataNon-response may not have been randomIllusion of control

Implications

Reduction in marijuana use a processTarget momentary desireAssess not just whether, but what efforts made to

avoid use, and how these changeReinforce active avoidance strategiesMore research needed on efforts to avoid useEMI may be a good approach to targeting these

variable and modifiable momentary phenomena