E-cigarettes: Craving, Quitting & Addictive Potential - keeping up with a rapidly evolving phenomena

Dr. Lynne DawkinsDrugs and Addictive Behaviours Research Group (DABRG), School of Psychology

http://www.uel.ac.uk/psychology/research/drugs

SSA, York, November 2014

Disclosures

• E-cigarette Industry: – Research funding– Conference funding– Received products for research

• Tobacco Industry: – No conflict of interest

• Pharmaceutical Industry: – No conflict of interest

Overview

• Introduction to E-cigarettes (EC)• Effects on craving & withdrawal symptoms• Blood nicotine delivery• Addictiveness• Effectiveness for smoking cessation

First Generation EC

Second Generation EC

Third Generation EC (‘mods’)

Effects on Craving & Withdrawal Symptoms (WS)

• EC (1st gen) can reduce craving & WS in deprived smokers; not as effective as tobacco cigarettes (Bullen et al., 2010, Tob Con, 19; Vansickel et al., 2010, Can Epid Bio Prev, 19)

• Placebo (0mg nicotine) EC (1st gen) also associated with decline in craving after 5 mins.(Dawkins et al., 2012, Add Beh, 37)

Novice users’ experiences of EC use over one week

• ‘...I nearly fell out of a tree about 60 foot up and it was a real adrenaline boost and I needed something to take that away...that was the only time it really didn’t kick, you know, the craving away.’

• ‘I was sat in this French cafe and there’s just people all around me smoking and it’s like, nah, I just need to get out of here now... It (the EC) just wasn’t taking the edge off it’

Lawson, Cahill & Dawkins (2013); UKNSCC poster

Craving and WS: 2nd generation (refillable) devices

• Lower craving & WS after using nicotine vs. placebo (2nd gen) EC (Dawkins, Turner & Crowe, 2013;).

• Disposable cigalike vs. refillable device: both equally effective at reducing craving and WS (Dawkins et al., under review)

1st vs. 3rd generation devices

• 23 experienced EC users used a 1st gen cartomiser and 3rd gen device

• In 3rd generation condition:

– ‘Craving to vape’ lower (p<0.001)

– Satisfaction and hit higher (p<0.01)

– Plasma nicotine levels higher at all time points (p<0.001)

(Farsalinos et al., 2014)

EC: Blood nicotine delivery

Effective nicotine delivery with 1st

generation cartomiser

device in 14 regular users

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Dawkins & Corcoran (2014), Psychopharmacology, vol. 231

Nicotine delivery: 1st vs. 3rd generation device

Farsalinos et al. (2014), Scientific Reports, vol. 4

EC addictiveness

• EC: slower speed of nicotine delivery• Tobacco contains additives to increase

addiction• Vapers reported longer time to first vape

vs. time to first cigarette• 30% had tried to quit vaping; mostly ‘not

very successful’ (Dawkins et al., 2013; Addiction, 106)

EC vs tobacco cigarettes (TC) in a multiple choice procedure (MCP)

Crossover value was significantly higher for 10 TC

puffs ($1.50) compared with

10 EC puffs ($1.06).

Vansickel, Weaver & Eissenberg, 2012, Addiction, 107

Economic demand for EC vs. TC

Vapers had a lower unit price than smokers at breakpoint – i.e. smokers will pay

more for their puffs 0.000 0.500 1.000 1.500 2.000 2.500

0.000

0.500

1.000

1.500

2.000

2.500

Demand curve

Smokerslog C

Vaperslog C

Log Price per puff

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Campbell , Dawkins et al., in prep

Smoking Cessation

• In 8 cross-sectional studies of vapers:

• 42-99% of ex-smokers stated that EC had helped them to quit smoking

• 60-86% of smokers stated that EC had helped them to reduce no. of cigs per day.

Dawkins (2013) Addiction, 108; Etter (2010) BMC Public Health, 10; Etter (2011) Addiction, 106; Farsalinos (2013) Int J Envir Res & Pub Health; Foulds (2011) Int J Clin Pract, 65; Goniewicz (2013) Drug Alc Rev, 32; Kralikova (2013),Chest, 144; Siegel (2011) Am J Prev Med, 40

Randomised Controlled Trials (RCTs):

• ‘Categoria’ 23mg/ml nicotine EC vs. 17mg/ml nicotine EC vs. no nicotine EC

• 300 smokers (not intending to quit)

• 1 year abstinence rates: 13%, 9% and 4%(Caponnetto et al., 2013)

• ‘Elusion’ 16mg/ml nicotine EC vs. no nicotine EC vs. nicotine patch

• 657 smokers followed up over 6 months

• 6 month abstinence rates: 7.3%, 4.1% and 5.8%

(Bullen et al., 2014)

Issues with RCTs:

• Expensive

• Time-consuming

• Out of date quickly in a rapidly changing market with fast moving technology

• Ecologically valid? Not reflective of what actually happens (EC users do not stick to a single product and liquid)

Conclusions

• EC can help to alleviate craving and WS...

• ...and raise blood nicotine levels

• Craving relief, nicotine delivery & addictiveness all lower in EC vs TC

• RCTs suggest e-cigs at least as effective as NRT...

• ...but trials with newer products needed

• Effectiveness for cessation will depend on a host of political, regulatory, technological and sociocultural factors

Acknowledgements

• John Turner• Kirstie Soar• Catherine Kimber• Victoria Lawson• Sharon Cahill• Eaodine Crowe• Olivia Corcoran• Maya Campbell