The Effect of Electronic Cigarettes

on Smoking Cessation and

Smoking Initiation

Nancy Rigotti, MD

Professor of Medicine, Harvard Medical School,

Massachusetts General Hospital,

Boston, Massachusetts, USA

nrigotti@partners.org

Refillable

ELECTRONIC CIGARETTESNew Nicotine Delivery Devices

• Deliver nicotine without smoke

• Devices are evolving

• We have more questions than

answers about their effects

ELECTRONIC CIGARETTESEffect on Public Health Depends on 3 Factors

Do they help smokers to stop smoking cigarettes?

Do young people use them → nicotine addiction

→ transition to smoking cigarettes?

Do e-cigarettes have health risks of their own?

Compared to smoking cigarettes (adults)

Compared to no smoking (youths)

#eCigHealthEffects

2018 U.S. Report on E-cigarettesBackground

The FDA Center for Tobacco Products asked the

U.S. National Academies of Sciences, Engineering &

Medicine (NASEM) to make a report:

To evaluate the evidence about the health

effects related to the use of e-cigarettes

To identify future research needs

4

#eCigHealthEffects

2018 U.S. Report on E-cigarettesMethods

A multi-disciplinary committee of experts:

Searched the literature

February 1, 2017 - August 31, 2017

>800 studies were found and reviewed

Made conclusions based on the amount and

quality of evidence available

5

#eCigHealthEffects

Conclusions are based on

level of evidence

Conclusive

Substantial

Moderate

Limited

Insufficient

No available(≠ evidence of no effect)

6

EVIDENCE SUMMARYNASEM Report – January 2018

▪ E-cigarettes contain fewer (and

lower levels) of toxic substances

than conventional cigarettes

▪ While not without health risks,

they are likely to be far less

harmful than combustible

tobacco cigarettes

▪ The long-term health effects of

e-cigarettes are not yet clear

EVIDENCE SUMMARYNASEM Report – January 2018

▪ Using e-cigarettes may help adults quit smoking

combustible tobacco cigarettes, but more research

is needed

▪ Among youth, e-cigarette use increases the risk of

initiating smoking of combustible tobacco

cigarettes

▪ Modelling results indicate that e-cigarettes will

likely result in a net public health benefit

#eCigHealthEffects

Smoking Cessation

• Will e-cigarettes increase smoking cessation

rates at the population level?

• POPULATION IMPACT = EFFICACY x REACH

– Efficacy: Do they help smokers to quit combustibles?

• How do they compare to existing cessation aids in

efficacy and safety/tolerability?

– Reach/appeal: Do they encourage more smokers to

try to quit combustibles?

• Smokers who are not interested in quitting or who

repeatedly failed and have given up trying

#eCigHealthEffects

Adult Smoking Cessation

• Literature review

– >20 systematic reviews• Best: Hartman-Boyce 2016 (Cochrane), El Dib 2017 (WHO)

• Generally agree that evidence is slim to make definitive

conclusions

– 3 RCTs – 2 with longitudinal data

• Bullen 2013 (nicotine e-cig vs. PCB e-cig vs. NRT)

• Caponnetto 2013 (nicotine e-cig vs. PCB e-cig)

– Use 1st generation devices, offer little/no behavioral support,

smokers vary in intention to quit, limited comparisons

#eCigHealthEffects

Adult Smoking Cessation

• Longitudinal observational studies– Results are often at odds with results of RCTs

– Few studies account for important covariates that may affect the

success of e-cigarettes as cessation aids.

• the e-cigarette product

• pattern of current use (frequency of use, duration of use)

• user characteristics (interest in quitting, etc.)

• Population-level studies (mostly cross-sectional)

• Cessation appears related to more frequent use

#eCigHealthEffects

Adult Smoking Cessation

• Limited evidence that e-cigarettes may

be effective aids to promote smoking

cessation overall

#eCigHealthEffects

Adult Smoking Cessation

• Moderate evidence from RCTs that e-cigarettes with

nicotine are more effective than e-cigarettes without

nicotine

• Insufficient evidence from RCTs about the

effectiveness of e-cigarettes as cessation aids

compared with no treatment or to FDA–approved

smoking cessation treatments

• Moderate evidence from observational studies that

more frequent use of e-cigarettes is associated with

increased likelihood of cessation

#eCigHealthEffects

Smoking Cessation Research Needs

• RCTs testing effectiveness of e-cigarettes as

cessation aids

– Especially to compare e-cigarettes to approved

smoking cessation pharmacotherapies, or test the

added value of e-cigarettes when added to proven

cessation aids.

#eCigHealthEffects

Youth & Young Adult SmokingResearch Questions

Among adolescents and young adults with no

history of combustible tobacco use:

1. Does e-cigarette use affect risk of ever use of

cigarettes?

2. Does e-cigarette use affect risk of progression to

regular smoking?

Assessed by frequency, intensity, or duration of use

#eCigHealthEffects

Youth & Young Adult SmokingLongitudinal Observational Studies

Past 30 day tobacco product use by high school students

U.S. National Youth Tobacco Survey, 2011–2017

MMWR 2016:65:361-7

#eCigHealthEffects

Youth & Young Adult SmokingEver Use Conclusion

• Substantial evidence that e-cigarette use

increases risk of ever using combustible tobacco

cigarettes among youth and young adults

#eCigHealthEffects

Youth & Young Adult SmokingSmoking Progression Conclusions

Among youth and young adult e-cigarette users who ever

use combustible tobacco cigarettes, there is:

• Moderate evidence that e-cigarette use increases the

frequency and intensity of subsequent combustible

tobacco cigarette smoking

#eCigHealthEffects

Harm ReductionConclusions

Complete Switching • Conclusive evidence that complete substitution of

e-cigarettes for combustible tobacco cigarettes reduces

users’ exposure to toxicants and carcinogens present in

combustible tobacco cigarettes

Dual Use• No available evidence whether dual use changes

morbidity or mortality compared with those who only

smoke combustible tobacco cigarettes

#eCigHealthEffects

Modeling of E-cigarette Use

• Mendez-Warner population dynamic model of smoking

prevalence and health effects

• Using a range of estimates for the effects of e-cigarettes

on cessation and initiation, the model projected years of

life lost or saved up to 2050 and 2070.

• Under most scenarios, the model projects that e-

cigarettes will produce a net public health benefit

through 2050.

21

#eCigHealthEffects

Visitnationalacademies.org/

eCigHealthEffects

to download the full

report

#eCigHealthEffects

▪ Sleek high-tech design

▪ Better nicotine delivery

▪ Marketed by social media

The JUUL Phenomenon

twitter

Instagram

Magazine ad

JUUL = now the market leader

Source: King B et al. JAMA 2018; 320:1379.

“The FDA now believes that youth use of

e-cigarettes is reaching epidemic

proportions.”

▪ Sales trends

▪ News coverage

▪ 2018 National Youth Tobacco Survey preliminary data

(~75% increase in use in high school students)

FDA Statement - September 12, 2018

▪ Fine >1300 retailers who sold JUUL to youth

▪ Most often sold: JUUL,Vuse, MarkTen XL, blu, Logic

▪ Manufacturers of these 5 products have 60 days

to show plans “describing how they will address

the widespread youth use of their products.”

▪ Or FDA may ban internet sales of e-cigarettes,

ban flavorings, or take other actions.

FDA Actions - September 12, 2018

How should you advise a smoker?

My clinical advice (Rigotti, Annals of Internal Med. 2018)

They are less harmful than continuing to smoke cigarettes

Many questions remain about e-cigarettes’ safety and

effectiveness for quitting

Recommend using approved treatments first

Don’t discourage if smoker insists and has failed other

methods

If plan to use, switch completely to e-cigarettes (no dual use)

Encourage patients using e-cigarettes to plan to stop e-cigarettes

in the future