Can E-cigarettes Help Curb the Smoking Epidemic in China?

Transcription

1 Can E-cigarettes Help Curb the Smoking Epidemic in China? Yantao Zuo, Ph.D. Department of Psychiatry & Behavioral Sciences Duke Center for Smoking Cessation Duke University Medical Center

2 Thanks to: DKU Education & Research Innovation in China (ERIC) Funding DKU Administrative Support Abu Abdullah, Ph.D. Main Research Funding: NIH/NIDA Disclosure of Conflict of Interest: None

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4 The Smoking Epidemic in China

5 % Smoking Rates (% of Ages 15+) in China Malaysia UK USA Male Female Source: WHO

6 In China, 2010: 300 million smokers. 740 million non-smokers exposed to secondhand smoke. Tobacco use responsible for 1.4 million premature deaths. Chinese Center for Disease Control and Prevention, 2011; Yang G et al Lancet 381:

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9 Why Do People Smoke?

10 What Do Smokers Say? Relief of Craving/Withdrawal: It satisfies my craving. Cognitive Enhancement/Stimulation: It helps me concentrate. It wakes me up when I am drowsy. It gives me a rush. Reduction of Negative Affect/Comfort: It calms me down. It makes relaxing seem even better. Sensorimotor Effects: I like the taste and smell. I like the sensations deep in my throat or chest. It gives me something to do with my hands. Automaticity/Habitual Behavior: I find myself smoking without remembering lighting up. Weight Control: It helps me control my weight. Reasons to Smoke questionnaire

11 What Do Lab Results Tell Us? Gilbert et al Nic Tobac Res, 6:

12 Self-medication hypothesis: Affective disorders are associated with higher smoking rates and heavier smoking. Zuo et al Psychopharmacol, 234:

13 Environmental Cues-Nicotine Conditioning Contributes to Persistent Nicotine Self-Administration If nicotine functions as a reinforcer to maintain tobacco smoking, it is likely that its reinforcing actions are magnified by interactions with interoceptive and exteroceptive stimuli associated with smoking Goldberg et al. (1981). Science. 214:

14 Sensorimotor Effects Contribute to Smoking Reward Rose et al. (1984). Addict Behav. 9:

15 [The] abuse liability of a psychoactive substance is partially related to the bioavailability of the drug and the speed of its delivery Benowitz et al. (1988). Clin Pharmacol Ther 44: Henningfield & Keenan (1993). J Consult Clin Psychol 61:

16 Brain Nicotine Kinetics Following Inhalation of a Puff of Smoke Zuo et al. (2015). Neuropsychopharmacol. 40:

17 Self-Titration of Nicotine Intake & Smoking Compensation Rose et al. (2010). PNAS 107:

18 Why is Fast Nicotine Kinetics Crucial for Nicotine Addiction? Picciotto et al Prog Neurobiol 84: Campling et al PLOS ONE 8:e79653.

19 Intermediate Summary: Addictive Effects of Smoking Nicotine s powerful modulation of cognition, affect, motivation, and physiology Fast nicotine kinetics via inhalation Self-titration of nicotine intake Conditioning between nicotine and rich sensorimotor stimuli Automaticity and habit-forming

20 Smoking is Hard to Quit. Even with the Best Cessation Treatments, Long-term Abstinence Rates are Low. Is There a Less Harmful Substitution for Smoking? What about E-cigarettes?

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22 China: Origin and Predominant Manufacturers of E-cigarette Products Invented by pharmacist Hon Lik ( 韩力 ) in 2003 as a smoking cessation aid. >90% of E-cig products were manufactured in China (Barboza, 2014). Tobacco companies may take over the E-cig industry. Barboza D. (2014, December 13). Online news report.

23 Tobacco Companies That Have Acquired or Created E-Cigarette Companies and Brands (as of January 2014) Grana et al Circulation 129:

24 Determinants of Nicotine Delivery from E-cigs Heating element design Battery power e-liquid nicotine concentration e-liquid propylene glycol (PG)/vegetable glycerine (VG) composition User experience Image Source: Google Search

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28 How Closely Can E-cigs Simulate Conventional Cigarettes? Using PET and C11-Nicotine to directly measure nicotine kinetics: E-cigarettes vs. conventional cigarettes

29 Zuo et al J Neurosci Methods. 282:

30 Nicotine, ng / kg brain tissue Brain Nicotine from a Single Cigarette Smoked in Naturalistic Environment (Mean ± SE, n=31) Smoking Time, min

31 Nicotine, ng / kg brain tissue Can We Match Temporal Profile of Brain Nicotine from Smoking Cigarette by Using E-Cig? Smoking E-cig 0.2mg, 41sec, 10p E-cig 0.28mg, 41sec, 10p E-cig 0.14mg, 20sec, 19p Time, min Courtesy of Alexey Mukhin

32 E-cig Nicotine Delivery Can Exceed That of Conventional Cigarettes Experienced E-cig Users 10 puffs Ramoa et al Tob Control 25:e6-e9.

33 Behavioral Effects of E-cig Use E-cig use attenuates cigarette craving/withdrawal. E-cig use improves cognitive performance. E-cig use reduces smoking. E-cig use devalues smoking reward. Adriaens et al Int J Environ Res Public Health 11: Bullen et al Tob Control 19: Dawkins et al Addic Behav 37: Dawkins et al Psychopharmacol 227: D Ruiz et al BMC Public Health 15:991. Polosa et al Intern Emerg Med 9:

34 Efficacy of E-cigarettes in Smoking Cessation Randomized controlled trials show limited efficacy. Cohort studies show mixed results. Cross-sectional studies show e-cigarettes help smokers quit. Farsalinos Ther Adv Respir Dis 12:1-20. Grana et al Circulation 129:

35 Are E-cigarettes Safer than Traditional Cigarettes? Though we can t say e-cigarettes are 100% safe, experts overwhelmingly agree that they are considerably less harmful than traditional cigarettes. Some experts estimate that e-cigarettes are 95% safer than traditional cigarettes. (Hartmann-Boyce et al. BMJ 2018;360:j5543) there is agreement that they are not absolutely harmless. (Farsalinos. Ther Adv Respir Dis 2018;12:1-20) Studies conducted in people using e-cigarettes to quit smoking have not detected serious adverse effects The most frequently reported adverse events across studies were mouth and throat irritation, cough, nausea, and headache, usually dissipating over time. (Hartmann-Boyce et al. BMJ 2018;360:j5543) Tobacco Advisory Group of the Royal College of Physicians. Nicotine without smoke: tobacco harm reduction.royal College of Physicians, Grana et al Circulation 129:

36 % of smokers trying to atop Aids used in quit attempt in past 12 months in England E-cigs Licensed NRT Champix Behavioural supp 39.5% 26.4% 6.5% 4.1% N=7,796 adults tried to stop or who stopped in the past year; respondents could use more than one method. West R, Beard B, Brown J. Trends in electronic cigarette use in England: Smoking Toolkit Study.

37 E-cigarettes are the most popular quitting method in England. Can E-cigarettes Help Curb Smoking in China? Very Likely Most Likely. Public Health England. Highest smoking quit success rates on record

38 E-cigarettes as a less harmful substitution for tobacco cigarettes: A summary

39 Cigarette-Like Nicotine Delivery Self-Titration of Nicotine? Sensorimotor Stimuli? Reduction of Smoking Reward Modulation of Cognition/Mood Aiding Smoking Cessation? No Smoke Exposure? No Second-hand Smoke Exposure? Toxicant Exposure Low Second-hand Toxicant Exposure Very low Safer than Conventional Cigarettes CONCERNS Maintenance of Nicotine Addiction Likely Maintenance of Dual Use Likely Long-term Health Hazards? Lack of Regulations Appeal to Youth

40 Conclusions Habitual smoking is maintained by powerful conditioning between rich cues and reinforcing effects of fast nicotine delivery. E-cigs are promising as a widely-accepted, less harmful substitution for smoking and an aid in smoking cessation owing to their close simulation of nicotine pharmacology and non-pharmacological aspects of smoking without smoke exposure. China lags behind many countries in the awareness and use of E-cigs. Research is justified to look into whether and how E-cigs can be used in China to more effectively combat the world s largest smoking epidemic.

41 COLLABORATORS DUMC Alexey Mukhin Jed Rose Wake Forest Univ. School of Medicine Kiran K Solingapuram Sai Pradeep Garg Sudha Garg Rachid Nazih Southern Illinois University at Carbondale David Gilbert Norka Rabinovich

42 Interested in Getting Research Experience? We Need Student Research Assistants Duke Kunshan University students are needed for a study on current use and perception of electronic cigarettes in China. You will get: training for human subject research; hand-on experience in multiple approaches of data collection and data analysis paid for your time as a research assistant. Interested? Please contact abu.abdullah@dukekunshan.edu.cn