Racial Differences in Circadian and Sleep Mechanisms for Nicotine Dependence, Craving, and Withdrawal

The number one preventable cause of death in the world is tobacco use. Cigarette smoking in particular, costs an estimated $300 billion due to expenses related to medical care and lost productivity. Despite similar smoking prevalence rates, blacks suffer disproportionately from smoking-related harms compared to whites.Sleep disparities such as shortened sleep duration, shorter circadian periodicity, earlier chronotype, and increased variability of sleep timing have been reported more frequently in blacks compared to whites. Given that poor sleep quality predicts relapse from smoking cessation programs, particularly among socioeconomically disadvantaged adults, sleep deficiencies and irregular timing of sleep may impact smoking craving and withdrawal symptoms over the course of the 24-hour day. Surprisingly, few studies have examined these temporal patterns of smoking and craving, and none with regard to sleep disruption, chronotype or racial disparities. A better understanding of these factors may explain heterogeneity within the smoking population, especially in minorities. Thus, the purpose of this proposal is to test the central hypothesis that the impact of chronotype and impaired sleep on cigarette usage as well as smoking dependence, urge/craving, and withdrawal depends on race.

Three specific aims will determine: contributions of sleep timing and sleep quality and quantity to racial disparities in smoking status (Aim 1), objective sleep characteristics and smoking behavior among blacks and whites who smoke cigarettes (Aim 2), and whether sleep restriction modifies craving and withdrawal in racially diverse smokers (Aim 3). Specifically, we will utilize self-report questionnaires, objective measures of sleep quality and timing (actigraphy) and circadian phase (dim light melatonin onset), as well as ecological momentary assessment of cigarette use, smoking urges, cravings, and withdrawal symptoms to identify circadian and sleep characteristics that are most strongly associated with smoking status, heaviness of smoking and dependence among blacks and whites. Finally, we will test whether acute sleep restriction (4 hours of time-in-bed) versus sleep extension (10 hours of time-in-bed) modifies craving and withdrawal symptoms following cessation in black and white smokers. If successful, the results of this study will result in identification of circadian dysfunction and insufficient sleep as mechanisms that underlie the association between sleep and cigarette smoking behaviors and dependence in diverse populations. Moreover, these findings are likely to inform clinicians of the importance of sleep and sleep timing on cigarette smoking behaviors and dependence that will help in the development of novel interventions to reduce morbidity and mortality caused by tobacco use.

Eligibility Criteria:
Sub-Study 1

Inclusion Criteria:

1. 18 years or older
2. Able to read and speak English
3. Non-Hispanic African American (Black) or non-Hispanic white race
4. Daily smoker (5 or more cigarettes a day for the past one year and having smoked more than 100 cigarettes in lifetime) or non-smoker (smoked fewer than 100 cigarettes in a lifetime and no smoking-not even a puff- in the last year)
5. Currently residing in Alabama

   Exclusion Criteria:
6. Non-English speaking
7. Lives in restricted environment that does not allow smoking
8. Pregnant or lactating
9. Daily or exclusive use of other tobacco products (e.g., cigars, e-cigarettes) if a smoker; if non-smoker, any other tobacco product use is exclusionary
10. Currently receiving smoking cessation treatment or using electronic cigarettes or other tobacco to try and quit smoking cigarettes
11. Participants would work outside normal 7 a.m. to 6 p.m. hours
12. Former smokers

Sub-study 2

Inclusion Criteria:

1. 18 years or older
2. Able to read and speak English
3. Non-Hispanic African American (Black) or non-Hispanic white race
4. Daily smoker defined as smoking 5 or more cigarettes a day for the past one year and having smoked more than 100 cigarettes in lifetime, as well as by an expired Carbon Monoxide (CO )cut-off of Carbon Monoxide (CO)\>10ppm and positive cotinine test to ensure daily smoking OR non-smoker defined as smoking fewer than 100 cigarettes in a lifetime and no smoking-not even a puff- in the last year, as well as by an expired Carbon monoxide (CO) cut-off of Carbon Monoxide (CO)\<3 ppm and negative cotinine test.
5. Currently residing in Alabama

   Exclusion Criteria:
6. Non-English speaking
7. Lives in restricted environment that does not allow smoking
8. Pregnant or lactating
9. Testing positive on urine drug screen test at baseline - any drugs other than Tetrahydrocannabinol (THC) not allowed
10. Daily or exclusive use of other tobacco products (e.g., cigars, e-cigarettes) if a smoker; if non-smoker, any other tobacco product use is exclusionary
11. Currently receiving smoking cessation treatment or using electronic cigarettes or other tobacco to try and quit smoking cigarettes
12. Participants would work outside normal 7 a.m. to 6 p.m. hours
13. Former smokers
14. History of a medical condition (e.g., bipolar disorder, migraine, or seizure disorder) that might be exacerbated by sleep deprivation as a result of Study 3
15. History of a serious lung/breathing disease that prevents one from walking or holding their breath for 10 seconds (in order to complete Carbon Monoxide breath test)
16. Cognitive impairment such that participant is unable to provide informed consent
17. Acutely suicidal, manic, acutely intoxicated, or otherwise not stable enough to provide informed consent
18. Living outside of the Birmingham metro area (\> 20 miles away from University of Alabama at Birmingham Main Campus)

Sub-study 3

Inclusion Criteria:

1. 18 years or older
2. Able to read and speak English
3. Non-Hispanic African American (Black) or non-Hispanic white race
4. Daily smoker defined as smoking 5 or more cigarettes a day for the past one year and having smoked more than 100 cigarettes in lifetime, as well as by an expired Carbon Monoxide (CO) cut-off of Carbon Monoxide (CO)\>10ppm and positive cotinine test to ensure daily smoking
5. Currently residing in Alabama

   Exclusion Criteria:
6. Non-English speaking
7. Lives in restricted environment that does not allow smoking
8. Pregnant or lactating
9. Daily or exclusive use of other tobacco products (e.g., cigars, e-cigarettes) if a smoker; if non-smoker, any other tobacco product use is exclusionary
10. Currently receiving smoking cessation treatment or using electronic cigarettes or other tobacco to try and quit smoking cigarettes
11. Participants would work outside normal 7 a.m. to 6 p.m. hours
12. Former smokers
13. History of a medical condition (e.g., bipolar disorder, migraine, or seizure disorder) that might be exacerbated by sleep deprivation as a result of Study 3
14. Currently taking any psychiatric medications, pain medications (i.e., opioids), or sleep medications (e.g., Ambien, trazodone, melatonin pills, Cannabidiol (CBD) products)
15. History of a serious lung/breathing disease that prevents one from walking or holding their breath for 10 seconds
16. Testing positive on urine drug screen test at baseline - any drugs other than Tetrahydrocannabinol (THC) not allowed
17. Has an apnea-hypopnea index (AHI) score of \> 15 on home sleep testing that was conducted during sub-study 2
18. Uses Continuous positive airway pressure (CPAP) machine to sleep at night
19. Cognitive impairment such that participant is unable to provide informed consent
20. Acutely suicidal, manic, acutely intoxicated, or otherwise not stable enough to provide informed consent
21. Living outside of the Birmingham metro area (\> 20 miles away from University of Alabama at Birmingham Main Campus)