Study of Smoking Abstinence

Background

Relapse following cigarette abstinence remains a common problem for smokers attempting to
quit. Extensive research has focused on the acute withdrawal phase that occurs within the
first 48 hours to one week; however, this study will focus on longer durations of
abstinence. Current clinical wisdom suggests that the rate of relapse decreases as the
length of abstinence increases; however, animal studies indicate that reactivity to
drug-related cues actually increases over time, an effect that has not been studied in
humans.

Scientific Goal

To examine the time course of cue reactivity in smokers who have been abstinent for 7, 14,
and 35 days.

Participant Population

A total of up to 420 smokers who are planning to quit in the future, but not right now, and
are willing to undergo a practice quit attempt. Target enrollment will include 50% women and
50% minorities (mostly African-American).

Experimental Design and Methods

Smokers (N=420) will participate in one of 4 groups over a period of 24 to 52 days in
sessions conducted in at the National Institute on Drug Abuse Intramural Research Program at
251 Bayview Blvd, Suite 200, Baltimore, MD 21224, and in a separately approved site, the
Human Behavioral Pharmacology Laboratory (HBPL, L484-496, 5841 S. Maryland Ave., Chicago,
IL, 60637). We expect that 190 participants will successfully complete the withdrawal phase
(N=50 in groups 1, 2, and 3a, N=40 in group 3b).

Participants will be randomly assigned to abstain from all nicotine use for 7, 14, or 35
days and participate in one cue-reactivity session on day on the last day of abstinence
(groups 1, 2, and 3a; N=50 per condition). The cue-presentation task will involve visual,
olfactory, and tactile cues. After cue presentation, participants will complete the Brief
Questionnaire of Smoking Urges and other standardized mood questionnaires. Physiological
responses and auditory reaction time will be obtained. Group 3b (N=40) will also abstain for
35 days, but will complete the cue-reactivity task two additional times to provide a
within-study examination of the changes in cue reactivity over long periods of abstinence.
On each laboratory visit, participants will give a urine sample to be tested for cotinine
and a breath sample to be tested for carbon monoxide (CO) to verify abstinence from smoking.
Participants will receive $20 in cash if both tests are negative, and they will accumulate a
further $10 to be paid as a bonus at the end of the abstinence phase. After their required
abstinence period of 7, 14, or 35 days, participants will enter a five-day step-down period
during which they will continue to report to the laboratory for 10 min a day, and they will
receive payments for abstinence in descending value across days. One of the primary outcome
measures in the study is the time to return to smoking, beginning from the last day of
required abstinence. After the step-down period, for the final 12 days of the study,
volunteers will report to the lab every 3 days to give urine and breath samples and to
report the number of cigarettes smoked. Participants will receive $15 for each visit to the
laboratory, and they will receive an end-of-study bonus of $25 for attending all visits.
This money will be paid regardless of whether they abstain from smoking.

Benefits to Participants and/or Society

There is no direct benefit to participants. These studies will provide the basis for future
studies investigating relapse to drug use. They will also shed light on the role of cue
reactivity and impulsivity in relapse. Knowledge about the time course of relapse will
provide important information about the processes underlying drug use and relapse.

Risks to Participants

The risks to participants are minimal. Participants will be healthy cigarette smokers who
will abstain from smoking for varying periods of time and may have increased craving at the
end of the experimental cue-exposure session. They will be given guided relaxation at the
end of the session to reduce craving to pre-session levels and will be fully debriefed
following the study. Some participants experience depression or other adverse symptoms
during nicotine withdrawal. These will be fully described to the participants, and, if the
symptoms become severe, the psychologist/counselor will counsel participants. The only other
risks involve loss of confidentiality from information obtained during screening.

- INCLUSION CRITERIA:

1. Age 18 years or older

2. Smoke at least 10 cigarettes per day, answer yes to the question Do you want to
quit smoking eventually?, but no to the question Are you currently planning to
quit?

EXCLUSION CRITERIA:

1. Medical conditions that would contraindicate participation

2. Medical conditions requiring medications that would contraindicate participation

3. Electrocardiogram suggestive of cardiovascular disease, symptomatic arrhythmia, QTc
interval > 450 ms; heart block greater than first degree.

4. Any current Axis I psychiatric disorder including Substance Use Disorder (except
Nicotine Dependence), or any history of psychosis;

5. Cognitive impairment (estimated IQ less than 80)