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 MDProfessor of Medicine, UCSF

AMERSA ConferenceNov 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

• Heats a nicotine solution to create an aerosol for inhalation

What is an electronic cigarette?

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 E-cigarettes

• 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 non-

user has right to clean indoor air

CS EC CS0

1

0.74

0.13

0.02

Air Nicotine(mg/m3)

CS ES C0

0.5

0.38

0.19

0.07

Saliva Cotinine(ng/ml)

Nonsmokers living with cigarette smokers (CS)e-cigarette users (EC) or no exposure (C)

Passive Exposure to Nicotine fromCigarettes v. E-cigarettes

The New England Journal of Medicine

Nicotine Poisoning in an Infant

DABS: The World’s Most Powerful AndSought 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-N EC-P Patch0

50

100

57

4541

Reduction in CPD (<50%)

%

P=0.08

EC-N EC-P Patch0

5

10

7.3

4.1

5.8

Quitting ( CAR )

P=0.05

EC Smoking Cessation RCT

6 month follow up

Real-world effectiveness of e-cigarettes 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

EC NRT No Aid0

10

2020.0

10.1

15.4

EC v. NRT

EC v. No Aid

0.0

0.5

1.0

1.5

2.0

1.63 1.61

** **

Real-world Effectiveness of E-cigarettesTo Aid Smoking Cessation

% Not-Smoking Odds Ratio

(** - 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)

EC NU0

5044.4 43.1

Complete Case Anal-

ysis

EC NU0

50

14.5

30

ITT

Quit Rates (%)

NU = non-user

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; re-

initiation 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