Project 1, Study 2: Extended Exposure to Low Nicotine Content Cigarettes in Childbearing Age Women

The primary overall objective of these studies is to evaluate the effects of extended exposure to cigarettes differing in nicotine content in socioeconomically disadvantaged (< high school educational attainment) women of childbearing age using a 3-condition, parallel groups design. After a baseline period in which daily smoking rate and other baseline assessments are completed, participants will be randomly assigned to one of three cigarette conditions (nicotine content: 0.04, 2.4, and 15.8 mg nicotine/gram of tobacco) for the 12-week experimental period.

The cigarettes to be used in this study were made under an NIH contract with production being overseen by the Research Triangle Institute (referred to as "Spectrum cigarettes"). NIH currently has approximately 10 million of these cigarettes (of varying types) for research purposes. The cigarettes selected for the study span the range of yields likely to produce the hypothesized effects, as described above. The Spectrum cigarettes are not currently commercially available, although they are similar in many ways to marketed cigarettes (e.g., similar manufacturing, filter, paper, etc.).

The primary overall objective of this study is to evaluate the effects of extended exposure to cigarettes differing in nicotine content in female adult smokers of childbearing age (18-44 yrs) whose highest academic degree is high school using a 3-condition, parallel groups design. After a baseline period in which daily smoking rate and other baseline assessments are completed, participants will be randomly assigned to one of three cigarette conditions (nicotine content: 0.04 mg, 2.4 mg, and 15.8 mg nicotine/g of tobacco) for the 12-week experimental period.

Participants will be seen weekly throughout the 12-week experimental period to obtain research cigarettes. Cigarettes smoked per day will be obtained by participants completing daily Interactive Voice Response (IVR) reports of cigarettes in past 24 hours. This daily data will be used to calculate weekly means, with week-12 means serving as the primary outcome.

This same study was conducted in two additional vulnerable populations under a similar protocol, with differences between protocols consisting of data collection specific to that vulnerable population. This included information such as use and timing of opioid maintenance therapy for individuals with opioid-use disorder or additional assessments of anxiety and depression for individuals with affective disorders. In order to explore potential differences across individuals with different vulnerabilities, data from all three studies were combined for analysis. A vulnerable population-by-condition or population-by-condition-by-time interaction term was included in all analyses. In the event that these interaction terms were statistically significant, all pairwise comparisons were conducted using a Bonferroni multiple comparison adjustment.

Inclusion criteria

• Female
• Ages 18-44 years
• Less than an Associate's degree
• Report smoking ≥ 5 cigarettes per day
• Provide an intake breath carbon monoxide (CO) sample > 8 ppm
• Be without current (within the past year) serious mental disorder that would interfere with study results or completion as determined by the Licensed Medical Professional or PI
• Be without current substance abuse/dependence other than nicotine
• Be sufficiently literate to complete research-related tasks
• Be in good physical health without serious illness or change in health or medication in the past three months as determined by the Licensed Medical Professional at each site
• Not pregnant or nursing and report using oral, implant, patch, ring, intrauterine device (IUD), injection, or barrier contraceptives or report being surgically sterile, or post menopausal
• Report no significant use of other tobacco or nicotine products within the past month (> 9 days in the past 30)

Exclusion criteria

• Any prior regular use (used as primary cigarette outside of the laboratory) of Spectrum cigarettes (i.e., research cigarettes with reduced nicotine content)
• Exclusive use of roll-your-own cigarettes
• Planning to quit smoking in the next 30 days
• A quit attempt in the past 30 days resulting in > 3 days of abstinence
• Currently taking anticonvulsant medications
• Positive toxicology screen for illicit drugs not including marijuana (participants with valid prescriptions will not be excluded and participants with a positive toxicology screen will be allowed to re-screen once)
• Breath alcohol level > 0.01 (participants with a positive screen will be allowed to re-screen once)
• Self-report of binge drinking alcohol (> 9 days in past 30, 4 drinks in 2 hours )
• Systolic blood pressure < 90 or ≥ 160 mmHg (participants outside the range will be allowed to re-screen once)
• Diastolic blood pressure < 50 or ≥ 100 mmHg (participants outside the range will be allowed to re-screen once)
• Breath CO > 80 ppm
• Heart rate < 45 or ≥ 115 bpm (participants outside the range will be allowed to re-screen once)
• Currently seeking treatment for smoking cessation
• Have used nicotine replacement, bupropion or other pharmacotherapies as cessation aids in the past month (bupropion for treatment of depression will be allowed)
• Current symptoms of psychosis, dementia or mania
• Suicidal ideation in the past month
• Suicide attempt in past 6 months
• Participation in another research study in the past 30 days