ema of treatment mediators and proximal predictors of smoking during a quit attempt danielle e....

EMA of Treatment Mediators and Proximal Predictors of Smoking

During a Quit Attempt

Danielle E. McCarthy, [email protected]

March 13, 2012

Smoking Cessation Laboratory

Tracking Impulsive Choice and Behavior

Learning Objectives

• Learn about discoveries regarding treatment mediators and proximal predictors of smoking made using EMA

• Learn about ways to use existing software to develop tailored self-report and cognitive and behavioral EMA

• Learn about the validity of real-time, field measures of impulsivity

2



Mediators of treatment effects

• Bupropion SR (McCarthy et al., 2008, Addiction)

– Positive affect on quit day– Craving decline 1st week– Motivation to quit 1st week– Self-efficacy 1st week

• Brief counseling (McCarthy et al., 2010, Addiction)

– Self-efficacy 1st month post-quit– Decline in perceived difficulty quitting

over 1st month post-quit3



Predictors of Point-Prevalence Abstinence• 3 months post-quit (N=70; McCarthy et al., 2006, J Abnormal)

– Pre-quit negative affect increases– Craving increases at outset of attempt

• 2 months post-quit (N=372; McCarthy et al., 2010, Addiction)

– Social support received– Access to cigarettes – Increasing attempts to prevent urges– Motivation to quit– Withdrawal distress– Post-lapse demoralization

• Stressful events 4



5

Stress Coping Smoking

Pre-Quit Coping Experience

Relations among coping, affect, and smoking over 48 hours (Minami et al., 2011, Addiction)

+

Negative Affect

Positive Affect

Urge Coping

Gender



6

Positive Affect

Smoking

Trigger exposure

Relations among affect, cognition, and smoking over 24 hours (Minami et al., in preparation)

Confidence

Motivation

Negative Affect

Time b/n reports



Current Study Questions

• Can impulsivity be measured in real time in subjects’ natural environments?

• Can real-time assessment tell us more about smoking cessation success than baseline assessment?

• What variables influence impulsivity within subjects?



How is impulsivity related to smoking?

• Smokers more impulsive than nonsmokers or ex-smokers (see Mitchell, 2004 for review)

• Impulsivity may be a marker for risk of cessation failure or relapse – Among recent quitters, delay discounting and

risk aversion predictive of relapse latency (Goto et al., 2009)

• Impulsivity may be dynamic– Discounting greater in drive states (Lowenstein,

2005; Giordano et al., 2002)



Study Design

• Prospective longitudinal study

• Smokers attempting to quit

• Followed 1 week pre- and 3 weeks post-quit– 4 EMA reports per day for 28 days

• All smokers received treatment– 4 15-minute individual counseling sessions

– 12-week supply of 2- or 4-mg nicotine lozenges



Participants

• Inclusion criteria:– At least 18 years of age

– At least 10 cigarettes per day for at least 6 months

– CO at least 8 ppm

– Able to read and write English

– Willing to complete 5 office visits and 4 EMA reports daily for 4 weeks

– Motivated to quit smoking (at least 6 on a 10-point scale)



Participants

• Exclusion criteria– Use of other tobacco, marijuana, or other drugs

in the past month

– Concurrent use of other stop smoking treatments

– Serious psychopathology (bipolar disorder, schizophrenia, other psychotic disorder)

– Contraindications to lozenge use

– Unwillingness to prevent pregnancy



Participants

• 99 adult smokers retained through quit date– 41% Female

– 6% Hispanic

– 70% White, 20% African American, 6% Asian American, 4% Other

– Age M=45.2, SD=11.7, Range=20-74

– Cigarettes/day M=18.9, SD=6.9, Range=10-40

– Fagerström Test of Nicotine Dependence M=5.3, SD=2.0, Range=1-9

– 27% CO-confirmed abstinence 3 weeks post-quit



Study Procedures

• Telephone screening• Orientation session

– CO testing– Questionnaires – ED training

• ED recording– Carry ED at all times, 4 3-5-minute reports per day

• Office visits– Five weekly visits over 5 weeks

• Follow-up– Phone call 12 weeks post-quit– Possible 5-minute office visit at 12 weeks

13



Baseline Measures

• Delay discounting– e.g., “Would you prefer $42 today or $100 in 1

week?”

– Delayed rewards of $20-$2500

– Delays of 1 day-2 years

– 26 series of items, up to 50 questions per series

– Used Johnson & Bickel, 2002 delay discounting algorithm to identify indifference points

– 1 choice up to $100 randomly selected to treat as real



Baseline Measures• Behavioral disinhibition

– Continuous Performance Task-II (Conners & MHS Staff, 2000)

– Press space bar for every letter but “X”

– “X” appears on 10% of trials

– 6 blocks of 60 trials

– Modified so trials with 1, 2, and 4 s inter-trial intervals interspersed randomly within blocks

– $0.02 for every correct response

– Feedback regarding errors and money earned between blocks



EMA Impulsiveness Measures

• Delay discounting– 8 items per report

– Rewards of $25-$100 at delays of 1-42 days

– One report treated as real

– Starting value of sooner reward (Vp=Vd /(1+kbaseD))

tailored to baseline discounting rate (kbase=1/D(Vd/Vp-1))

– Next sooner reward based on previous responses (midpoint between min and max indifference points)

– Final k based on estimated indifference point at 8th question (kEMA=1/D(Vd/Vp-1))



Sample Alarm ScreenAlarm screen

17

Alert

Friday, 7/13/201012:45 pm-1:00 pm

Private Appointment

Snooze Go ToClear

2210

83202138GO



EMA Discounting Instructions

83202138GO

Remember...

At least 1 of these choices will be REAL during the study!(Press Next to continue)

Previous Next

Welcome

Please indicate which option, A or B, you prefer by tapping the letter.(Press Next to continue)

Previous Next

Daily k .01



Sample EMA Discounting Items

Would you prefer?

1A. $ 24.27 today

1B. $ 25.00 in 2 weeks

Your choice:

Previous Next

A B

Would you prefer?

2A. $ 15.67 today

2B. $ 25.00 in 2 weeks

Your choice:

Previous Next

A B



Additional Items

20

PAST 15 MINUTES...

1 2 3 4 5

Disagree Agree

I have felt EXCITED

Previous Next

PAST 15 MINUTES…

Please answer the next questions based on how you have FELT IN GENERAL in the PAST 15 MINUTES.

(Press Next to continue)

Previous Next



Sample ED Items

21

PAST 15 MINUTES...

1 2 3 4 5Disagree Agree

I have felt EXCITED

OK

PAST 24 HOURS…

Not At All Extremely

How WILLING are you to WORK HARD AT QUITTING SMOKING?

Previous Next

I have felt EXCITED

Missing Response

Disagree Agree



Final Sample Item and Ending a Report

22

JUST BEFORE PROMPT:

Home

Work/School

Vehicle

Restaurant/Bar

Public Place

Others’ Home

Outside

Other

WHERE were you?

Previous Next

PAST 15 MINUTES…

Have you been with SOMEONE WHO WAS SMOKING?

Previous Next

Yes No



More Sample Items

23

PAST 2 HOURS…

How many CIGARETTES have you smoked IN THE PAST 2 HOURS?

Previous Next

PAST 2 HOURS…

Previous Next

Select one…

How many CIGARETTES

0123456789



EMA Measure of Behavioral Disinhibition

• 2-minute, 60-trial CPT-II• DV=Commission error rate

• MiniCog software (Shephard, Kho, Chen, & Kosslyn, 2006; Cambridge, MA)

– Custom programming of items through Adobe Dreamweaver (San Jose, CA)

– Some limits (no multi-screen trials)

– Reaction time temporal resolution ~10 ms

– Requires extra log-in step

– Randomization of items24



MiniCog

Next

Login ID l______

Notes ____________

__________

__________

Sample Questions

25

MiniCog

______________________Keyboard

1 2 3

4 5 6

7 8 9

( 0 )abc 123 Int’l

Done

2210

83202138GO



Instructions

You will see a series of letters appear on the screen one at a time.

Each time you see a letter, press the center GO key, except when the letter is an X. If the letter is an X, do nothing.

Please press the GO key to continue.

2210The rate at which the letters appear may vary– so pay close attention.

You will earn 2¢ for every correct response.

Please press the GO key to continue.

GO

• 2-minute, 60-trial CPT-II• DV=Commission error rate

GO



EMA CPT-II Task

F X H

GO GO GO



Delay Discounting 7,204 records from 99 subjects



Delay Discounting



Delay Discounting

*Jump



Delay Discounting

*Jump

*Slope



Delay Discounting*JumpSteeper in those high in cognitive instability

*SlopeSteeper in those high in cognitive instability



Delay DiscountingUnrelated to initial cessation failure or abstinence 3 weeks post-quit



Behavioral Disinhibition6,719 records from 91 subjects

*Slope



Behavioral DisinhibitionBaseline error rate related to

3-week abstinence; EMA rates not predictive



Discussion• EMA measures significantly related to

validated baseline behavioral measures

• Self-reported cognitive instability related to EMA discounting level and growth

• EMA measures did not predict abstinence above and beyond baseline measures



Limitations

• Interim analysis with limited power

• Imperfect adherence to EMA assessment schedule

• Smoking not controlled for in models

• Skew in discounting and disinhibition distributions



Future Directions

• Identify internal (e.g., craving) and contextual factors (e.g., exposure to smoking cues) associated with momentary fluctuations in impulsivity– Interim analyses suggest that positive affect,

but not negative affect, predicts change in k

• Examine short-term relations between changes in impulsivity and subsequent smoking



Collaborators

• Rutgers– Gretchen Chapman– Haruka Minami– Krysten Williams– Vivian Yeh– Haewon Yoon

• U. Pittsburgh– Saul Shiffman

39

• U. Wisconsin– Timothy Baker– Michael Fiore– Doug Jorenby– Daniel Lawrence– Megan Piper– Stevens Smith

• U. Missouri-Columbia– Thomas Piasecki



Questions?

Comments?

40

ema of treatment mediators and proximal predictors of smoking during a quit attempt danielle e....

Documents