Should Medical Providers
Recommend E-cigarettes to their
Patients as a Smoking Cessation
Tool?
There is not yet enough Evidence to
Recommend EC as a Primary
Cessation Aid
Neal L Benowitz MD
Professor of Medicine, UCSF
AMERSA Conference
Nov 7. 2014
Disclosures
• Consultant to pharmaceutical companies that
market smoking cessation products, including
Pfizer, GlaxoSmithKline and McNeil.
• Paid expert in litigation against tobacco
companies.
My position
If a patient has failed initial treatment, has been
intolerant to or refuses to use conventional
smoking cessation medication, and wishes to
use e-cigarettes to aid quitting, it is reasonable
to support the attempt.
AHA Policy Statement on Electronic Cigarettes, Circulation 2014
What is an electronic cigarette?
• Heats a nicotine solution to create an aerosol for inhalation
Clearomizer
Battery
Main components of EC aerosol
•
•
•
•
Nicotine
Propylene glycol
Glycerin
Flavorants
Three Generations of E-cigarettes
• Cigarette-like: “cigalikes”; Blu, Njoy, V2 Cigs
• Tank style: pen-like; various colors and
shapes; larger batteries and atomizers;
refillable tanks; eGo
• Mods: “personalized vapors”; range of
cartidge, atomizer, battery options; adjustable
battery voltage; refillable tanks; Apollo, Vapor
Zone
Unresolved questions about Ecigarettes
• Safety concerns
– For the user
– For non-smokers in close proximity to the user
– Accidental poisoning
• Are EC effective for smoking cessation?
• How do you counsel about products and how
they should be used?
• Potential adverse societal impact
Safety Concerns
EC liquid and vapor
•
•
•
•
•
•
Nicotine
Propylene glycol
Glycerin
Tobacco-derived nitrosamines
Particulates (including metals)
Volatile organic chemicals (acrolein,
formaldehyde)
• Flavorants
• Miscellaneous contaminants
Particulates from EC and Conventional Cigarettes
(Fuoco et al, 2013)
Battery Voltage Influences Levels of Carbonyls in EC Aerosol
Kosmider NTR 2014
Adverse Health effects of E-cigarettes
• Health effects of long-term use are unknown
• Based on toxicant analyses and a few clinical
studies, EC use like to be much less harmful
than cigarette smoking
• However since products are unregulated,
constituents of E-liquids vary widely
• Concerns about long term propylene glycol
and particulate exposure
E-cig store owner says lack of regulations results in
production in ‘basements and bathrooms’
Calgary Herald October 1, 2014
Secondhand E-cigarette Aerosol
Exposure
• Secondhand cigarette smoke (SHS) is hazardous; 75%
tobacco burned is sidestream smoke
• EC emissions exhaled by user only
• Ambient levels of nicotine, particulates and organic
chemicals from EC reported to be 10% of SHS
• Potential for environmental contamination with
nicotine
• Uncertain if any health hazard to non-user, but nonuser has right to clean indoor air
Passive Exposure to Nicotine from
Cigarettes v. E-cigarettes
Air Nicotine
(mg/m3)
1
Saliva Cotinine
(ng/ml)
0.5
0.38
0.74
0.19
0.07
0.13
0.02
0
0
CS
EC
CS
CS
ES
C
Nonsmokers living with cigarette smokers (CS)
e-cigarette users (EC) or no exposure (C)
The New England Journal of Medicine
Nicotine Poisoning in an Infant
DABS: The World’s Most Powerful And
Sought After Weed Product
E-cigarettes and smoking
cessation
Do E-cigarettes promote cessation or
reduce harm?
• Benefit for smoking cessation in smokers who
want to quit is suggestive but as yet
inconclusive
• Concerns that quitting could be inhibited in
smokers not contemplating quitting
• E-cig use reduces cigarette consumption by
dual users, but health benefits of reduction
not yet proven. Reduced cigarette smoking
might promote later quitting.
E-cigarette Smoking Cessation RCT
•
•
•
•
•
Quitline-based (minimal support)
Nicotine e-cigarettes (poor delivery) vs.
Zero nicotine e-cigarettes vs.
Nicotine patch (21 mg)
13 weeks treatment
EC Smoking Cessation
RCT
6 month follow up
Reduction in
CPD (<50%)
100
Quitting
( CAR )
10
P=0.08
P=0.05
7.3
%
50
5.8
57
45
41
0
5
4.1
0
EC-N EC-P Patch
EC-N EC-P Patch
Real-world effectiveness of ecigarettes to aid smoking cessation
(Brown et al. Addiction 2014)
• Cross-sectional household survey of UK
households, 2009-2014
• 5863 adult smokers who tried to quit in past
12 mos using EC, NRT (OTC) or no aid
• Outcome: self-reported abstinence
Real-world Effectiveness of E-cigarettes
To Aid Smoking Cessation
% Not-Smoking
Odds Ratio
2.0
20
20.0
1.5
1.63
1.61
**
**
EC v.
NRT
EC v. No
Aid
15.4
1.0
10.1
10
0.5
0
0.0
EC
NRT
No
Aid
(** - p < 0.01)
Brown et. al., Addiction 2014
E-cigarettes and Smoking Cessation in
Cancer Patients
(Borderud Cancer 2014)
• Cohort study of cancer patients attending
smoking cessation program at Memorial Sloan
Kettering Cancer Center 2012-2013
• 699 subjects, 56 yo, 26% EC users past 30 d
• Multicomponent behavioral and
pharmacologic treatment
• 6-12 month follow up
• Outcome: self-reported abstinence (7 d)
Quit Rates (%)
Complete
Case
Analysis
ITT
50
50
44.4
43.1
30
14.5
0
0
EC
NU
NU = non-user
EC
NU
Other Observations
• 92% EC users reported dual use
• E-cigarette users:
– Higher % with thoracic and head and neck cancer
– More CPD and higher level of dependence
– More frequent and longer duration of prior quit
attempts
– Higher % dropped out of treatment
– No reduction in CPD at follow up
Is there a benefit to smoking fewer
cigarettes per day?
• Probably not much for cardiovascular disease
• Probably some for cancer, COPD and
infectious disease risk
• Difficult to extrapolate from spontaneous
reduction studies due to compensation while
smoking fewer cpd – may be different with an
alternative source of nicotine
Possible Adverse Societal Effects of
Promoting E-cigarette Use
• Renormalization of smoking behavior
• Sustaining dual use (rather than quitting
cigarette smoking completely)
• Initiation of nicotine dependence in youth; reinitiation of nicotine dependence in former
smokers
• Undermining clean indoor air policies
Conclusions
• For most patients quitting smoking is the
single most important thing they can do to
improve health
• E-cigarettes are a promising new approach to
aid smoking cessation
• However the currently available products are
unregulated, with uncertain safety, uncertain
efficacy in promoting cessation, and with
potential adverse societal harm.
Conclusions
I am cautiously optimistic about E-cigarettes for
smoking cessation, but there is not yet enough
evidence to recommend E-cigarettes as primary
cessation aids.
We need adequate regulation of product safety
and good clinical trials of E-cigarette use for
smoking cessation.
My position
If a patient has failed initial treatment, has been
intolerant to or refuses to use conventional
smoking cessation medication, and wishes to
use e-cigarettes to aid quitting, it is reasonable
to support the attempt.
AHA Policy Statement on Electronic Cigarettes, Circulation 2014
Counseling your Patient
• The EC is likely to be much less toxic than
cigarette smoking, but …
• The products are unregulated
• ECs contain variable (and unpredictable) levels of
toxic chemicals
• ECs not proven effective as cessation device
• Consider setting a quit date for EC use (unless
needed to prevent relapse to smoking)
• Do NOT continue cigarette smoking