©
september/october 1997
EFFECTIVE CLINICAL
TOBACCO INTERVENTION
“It is difficult to identify a condition in developed
countries that presents such a mix of lethality, prevalence, and neglect, despite effective and readily
available interventions”1
S
o begins the U.S. clinical practice guideline on
smoking cessation. Canadian preventive experts
give clinical smoking cessation an “A” recommendation (good evidence for effectiveness)2. Importantly,
smokers place a physician-based approach at the
top of their list of methods to stop smoking 3.
What does smoking do to
people’s health?
Every second smoker dies from smoking. In Canada,
smoking causes 16% of ischemic vessel disease,
35% of cancer, and 77% of chronic lung disease 4.
Tobacco addiction causes more deaths than AIDS,
accidents, and drugs combined, and cigarette smoking
alone cost the people of BC $738 million in medical
expenditures in 1996.
Why do smokers keep smoking?
Nicotine is a powerful chemical that offers smokers
pleasure and reward, focuses attention, suppresses
hunger, calms stress, elevates mood, and relieves
nicotine withdrawal 5. Nicotine is both a stimulant
and a relaxant. In just seven seconds, the nicotine
from a cigarette binds to the brain’s nicotinic receptors after entering the pulmonary circulation and
crossing the blood-brain barrier. The pack-a-day
smoker repeats this process (puffs) 200 times per
day. Thus, nicotine drives the addiction to tobacco.
The evidence for addiction includes6:
• Fewer than 10% of smokers go a day without
a cigarette.
• Symptoms of tobacco withdrawal are reliably
reversed by nicotine.
• Experienced drug users, given various drugs, find
IV nicotine as satisfying as subcutaneous morphine.
Specific indicators (number of cigarettes per day,
time to first cigarette after awakening, and severity of withdrawal symptoms) reflect the intensity of addiction
and predict the (un)likelihood of stopping smoking 7.
How does tobacco addiction work?
Nicotine links to central receptors (cholinergic,
adrenergic, dopaminergic and serotonergic) to
produce the effects noted above 7. The mode of
delivery (whether smoking or nicotine gum or
patch) determines peak blood nicotine level and
time to peak level. Inhaling tobacco smoke delivers to the brain the highest and sharpest peaks of
nicotine and thereby maximizes its psychoactive
effects. Nicotine has a half-life averaging two
hours. Smokers usually begin their day with low
nicotine levels that rise sharply in the morning,
plateau in the afternoon when smoking slows, and
fall during sleep. Each smoker has a characteristic, 24-hour blood nicotine curve and maintains
blood nicotine levels within a specific range for
each hour of the day. When blood nicotine falls
beneath the smoker’s zone of comfort, withdrawal
symptoms may begin: anxiety, restlessness, inability to concentrate, irritability, severe urges to
smoke, reduced pulse rate, headaches, and problems with sleeping. If blood nicotine gets too high,
toxicity may appear: nausea, excessive salivation,
cold sweat, pallor, an increased pulse rate,
headaches, and problems with sleeping, particularly vivid dreams.
What do we know about
smoking behaviour?
Two thirds of new recruits to smoking are children,
between ages 9 to 16. Children, after they make
the transition to daily smoking, often move quickly
to early addiction.
The Therapeutics Initiative is at arms length from government and other vested interest groups. Our function is unbiased review and
dissemination of therapeutic evidence. Assessments apply to most patients; exceptional patients require exceptional approaches.
We are committed to evaluate the effectiveness of our educational activities using the Pharmacare database without identifying
individual physicians, pharmacies or patients. Please notify us if you do not wish to be part of this evaluation.
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september/october 1997
Adolescents identify physicians as a highly
credible source of information about
smoking. An individual’s smoking varies with their
age, geographic region, ethnic group, and the
smoking behaviour of their family, friends, and
workmates. The best predictor of smoking is
years of education: the more years, the
less likely the individual is to smoke. A
genetic component of nicotine addiction has been
established 8. Nicotine’s effects on mood are particularly powerful for people with disorders such as
schizophrenia, depression, alcoholism, and drug
addictions 9. In BC, ex-smokers out-number smokers.
However, half of present smokers have no plans to
quit and only one in seven BC smokers is ready to
stop smoking (a third of smokers are thinking about
stopping within six months). The vast majority of
those who stop smoking do so on their own, without
formal help. But few smokers manage to quit on
even their second or third attempt. Thus, the potential strength of medical care is to sustain and support smokers efforts to quit.
What non-drug interventions can the
clinician use to help patients quit smoking?
Brief interventions (e.g., personalized advice; then
asking, “How do you feel about stopping smoking?”; and listening empathetically for just 30-40
seconds) versus no intervention lead to an average
absolute increase in cessation at one year of
2.3%10. In other words, for every 43 patients who
receive brief intervention, one will quit smoking.
While this effect may seem small, one must remember that the extra 30-40 seconds required to do this
on each visit can markedly diminish a life-threatening risk. The transformation from smoker to ex-smoker usually requires significant neurochemical,
behavioural, and attitudinal changes. Treatment
tailored to the patient’s stage of readiness
to quit smoking accelerates the process 11.
Many years often pass from the first attempt to stop
smoking until the smoker goes for a year without a
puff. The patient’s struggle with smoking cessation
should be regarded as a chronic condition 12. In this
struggle, patients want their doctor to understand
their frustrations 13. Controlled trials demonstrate
two measures that independently increase smoking
cessation substantially 1: chart-reminders indicating
smoking status on all medical records (sticky label,
rubber stamp, or computer prompt) (absolute
increase 3%) and involvement of both doctor and
office staff (absolute increase 14%). The many smokers who are not ready to stop require no more than
brief listening and an empathetic statement.
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Controlled trials of mail-based tobacco interventions
suggest that motivating those smokers who are reluctant to quit produces as many new ex-smokers as treating those who are ready to quit.11,14. The few smokers
who are ready to quit will require more time for: problem solving, pharmacotherapy, and follow-up care
(optimally visits are scheduled within 3 days of the
quit date, 10-14 days later, and at 1,3,6, and 12
months)1. Systematic reviews and meta-analyses of the effectiveness of most interventions
are now available and updated regularly in
the Cochrane library.10
What pharmacological interventions
have proven effective?
Nicotine replacement enhances the chances of quitting
over clinician advice alone. All forms of nicotine
replacement are effective. 1,10. Nicotine patches, 2mg
and 4mg nicotine gum are presently available in
Canada; the nicotine nasal spray, and the nicotine
inhaler, both available in the U.S., may come to
Canada soon. Nicotine replacement should be offered
to smokers of five or more cigarettes per day who are
ready to stop smoking. Nicotine replacement reduces
disabling nicotine withdrawal, but it does not provide
the positive psychoactive benefits of smoking.
Nicotine gum
In patients who use nicotine gum, the absolute difference in cessation rates at one year is 6% 10. The likelihood of cessation is greater when motivated, selfreferred patients are treated (11% absolute difference)
than when the gum is offered to all smoking patients
(3% absolute difference)15. In patients with high
degrees of nicotine addiction, the 4mg gum is more
effective than the 2mg gum15. However, in smokers
with low levels of dependence, the 4mg gum has no
therapeutic effect10. In patients who self-refer and who
have high dependence, the 4mg nicotine gum produces an absolute difference in cessation rate of 35%
at one year 15. In British Columbia, 2mg and 4mg
nicotine gum do not require a prescription.
Nicotine patch
The absolute difference in cessation rates between
treatment and control groups with the nicotine patch is
9% 10. As with the gum, the benefit is greater in selfreferred patients (12% absolute difference) compared
with offering the patch to all smoking patients (6%
absolute difference) 15. The several patches available
have different nicotine delivery attributes, but there is
insufficient evidence to identify one patch as being
more effective than another. There is also insufficient
data to compare the effectiveness of nicotine gum with
that of nicotine patches.
continued on page 21b
september/october 1997
continued from page 21a
Table 1: Nicotine Replacement Drugs
Drug
Quantity/Price
Quantity/Price
30 pieces/$12
30 pieces/$13
105 pieces/$30
105 pieces/$39
7,14,21 mg
7,14,21 mg
7,11 mg
14 patches/$57
14 patches/$60
14 patches/$57
Nicotine gum 2 mg *
Nicotine gum 4 mg *
Nicotine patches **
Nicoderm
Habitrol
ProStep
* sold over-the-counter in BC.
** prescription currently required; price includes pharmacist’s fee.
The patch is much simpler to use than the gum, but is
not recommended for patients with sensitive skin nor for
those who want to control their nicotine levels.
Combining the patch with the gum may be helpful for
heavily-addicted smokers who can manage a complex
treatment plan16,17,18. Physicians who prescribe combined patch and gum treatment should obtain the
patient’s written consent because of the theoretical risk
from higher-than-usual levels of therapeutic nicotine.
Can nicotine replacement continue
long-term addiction to nicotine?
There is no evidence that the patch perpetuates nicotine
addiction. The gum occasionally sustains it (10-15% still
using gum after one year). Continued addiction is more
likely with the nasal spray (35-40% still using the nasal
spray after 12 months). However, being addicted to
nicotine alone is a healthier option than continued
heavy smoking.
What are the contraindications to
nicotine replacement therapy?
The following conditions contravene use of nicotine
replacement:
• immediate post-myocardial infarction
• life-threatening cardiac arrythymias
• severe or worsening angina pectoris
• temporomandibular joint disease (only contravenes
use of gum)
In patients with other conditions (e.g., ischemic heart
disease, hypertension, or pregnancy) clinical judgment
will determine whether to recommend stopping with or
without pharmacological treatment.
What other drugs can be used to treat
nicotine addiction?
Buproprion, an antidepressant available on an emergency release basis in Canada, at a daily dose of 300
mg, has been shown in 3 trials to produce a 12.5%
absolute difference in one-year smoking cessation
(22.5% for the drug versus 9% for placebo)10.
Fluoxetine and nortriptyline appear to also
increase cessation in single clinical trials 10. A
meta-analysis of 5 clinical trials of clonidine
demonstrates a 9% absolute difference in smoking
cessation; however, it produces unpleasant side
effects such as dry mouth, sedation, and dizziness1,10 A number of anxiolytics have been tested
in clinical trials with no benefit10. Bromocriptine
has been used for smoking cessation by a few
physicians but it has not been evaluated in a randomized clinical trial.
What strategies should guide
pharmacological therapy?
Begin by assessing the patient’s smoking: number
of cigarettes smoked per day; how soon the patient
has their first cigarette after arising; longest time
without a cigarette in the past year; severity of
withdrawal in the past; had a smoke-free year
since began smoking; had a smoke-free week in
past year. Ask the patient to indicate readiness to stop smoking by choosing a number from 1 (low) to 10 (high) and reserve
treatment for motivated smokers (>7).
Motivate the others with personalized advice and
brief listening. For those who are ambivalent about
stopping and for heavy smokers, one to three
weeks of monitoring smoking (recording the time
and place of each cigarette prior to lighting it) provides useful information, indicates the patient’s
commitment to stop smoking, and subtly modifies
smoking behaviour. A target date for stopping, set
by the patient, is useful. The patient should
understand the psychoactive effects of smoking
(stimulation, calming, reward, ritual) and how
treatment works.
The first line of pharmacological treatment is nicotine replacement. The smoker
should end smoking one day and begin the next
with enough medication to block withdrawal.
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september/october 1997
The nicotine medications for which the patient controls
dosage, i.e. the gum and the nasal spray, should be
taken on a scheduled rather than on an as-needed basis
in order to assure sufficient nicotine intake. For example, the patient who smoked hourly should plan on taking a 2mg gum hourly. Smokers should be monitored
for symptoms of withdrawal and toxicity and the dose
of nicotine adjusted accordingly.
Nicotine replacement can be maintained for 8-12
weeks. In clinical trials, 8 weeks of nicotine patch therapy was as effective as longer treatment10. Tapering the
dose from the 21mg (22mg) to the 14mg (11mg) patch
at four to six weeks may minimize withdrawal symptoms. However, tapering does not produce a net gain
in long-term cessation10. If a patient who uses nicotine
replacement properly does not stop smoking, other
pharmacological agents should be considered when
the patient is next ready to try again.
Patients with the following characteristics may require
more supervision and/or higher doses of nicotine
replacement:
• heavily addicted to tobacco, with many quit attempts
• addicted to other drugs including alcohol
• history of depression or schizophrenia
• severe poverty or psychological stress
• cessation is urgently required for medical reasons
References
1. Fiore MC, Bailey WC, Cohen SJ, et al. :Smoking Cessation. Clinical
Practice Guideline Number 18. Rockville, MD: U.S. Department of
Health and Human Services, Public Health Service, Agency for Health
Care Policy and Research. AHCPR Publication No. 96-0692, April, 1996.
2. Canadian Task Force on the Periodic Health Examination: The Canadian
Guide to Clinical Preventive Health Care. Ottawa; Minister of Supply and
Services Canada; 1994. pp XXXIX - XLIX.
3. Campbell, Goodell, Traynor, Consultants: The B.C. Consumer Omnibus
January 1996 Telephone Survey. Vancouver; Campbell, Goodell, Traynor,
Consultants, January, 1996, Table 8.
4. Peto R, Lopez AD, Boreham J, et al: Mortality from Smoking in Developed
Countries 1950-2000, Indirect Estimates from National Vital Statistics,
New York; Oxford University Press, 1994. p. 307.
5. Balfour DJK, Fagerström, KO: Pharmacology of nicotine and its therapeutic
use in smoking cessation and neurodegenerative disorders.
Pharmacol. Ther 1996 72: 51-81.
6. Royal Society of Canada: Tobacco, Nicotine, and Addiction. A Committee
Report. Ottawa; Royal Society of Canada, 1989.
7. Pierce JP, Evans N, Farkas AJ, et al: Tobacco Use in California: An
Evaluation of the Tobacco Control Program, 1989-1993. La Jolla, Calif;
Univ of Calif. San Diego; 1994. pp 164-167.
8. Carmelli D, Swan GE, Robinette D, et al: Genetic influence on smoking—
a study of male twins. New Engl J Med 1992 327: 829-33.
9. Resnick MP: Treating nicotine addiction in patients with psychiatric
co-morbidity, pp 328-329, in Orleans CT, Slade J (eds):Nicotine Addiction:
Principles and Management. New York; Oxford Univ Press; 1993.
10.Silagy C, Ketteridge S. The effectiveness of physician advice to aid smoking
cessation. Silagy C, Mant D, Fowler G, Lancaster T. The effect of nicotine
replacement therapy on smoking cessation. Gourlay SG, Stead LF,
Benowitz NL. A meta-analysis of clonidine for smoking cessation. Hughes JR,
Stead LF, Lancaster TR.Anxiolytics and antidepressants in smoking cessation.
In: Lancaster T, Silagy C, Fullerton D (eds.) Tobacco Addiction Module of
The Cochrane Database of Systematic Reviews, Available in The
Cochrane Library [database on disk and CD-ROM]. The Cochrane
Collaboration; Issue 3. Oxford: Update Software; 1997. Updated quarterly.
21b
Conclusion
The challenge for health care professionals is to:
• organize medical care so that the smoking status of all patients is identified and followed-up
• motivate smokers to stop and youth to avoid
the addiction
• offer those smokers who are ready to quit
behavioural and pharmacological treatment
and follow-up
The benefit is that 8-12% of all your smoking
patients will stop smoking annually, rather than
the 4-6% who stop with no intervention (absolute
increase 6%, number needed to treat to benefit
one patient, 17 per year)19. The long-term,
cumulative impact of physician based
tobacco intervention on smoking prevalence makes it one of the leading
options in tobacco control 20.
Programs to help health professionals
help their patients to stop smoking:
✪ B.C. Doctors Stop Smoking Program
Telephone: (604) 736-1226, local 278
Fax: (604) 736-3987
✪ Guide Your Patients to a Smoke Free Future
To Request Booklets, Fax: (604) 736-3987
✪ The Cancer Society, Lung Association,
Heart and Stroke Association, and
public health units have useful patient
education materials.
11.Strecher VJ, Kreuter M, Den Boer DJ, et al: The effects of computertailored smoking cessation messages in family practice settings.
J Fam Pract 1994 39: 262-70.
12.Fiore MC, Baker TB: Editorial: Smoking cessation treatment and
the Good Doctor Club. Am J Pub Health 1995 85: 161-162.
13.Willms DG, Best JA, Wilson DMC, et al: Patients’ perspectives of
a physician-delivered smoking cessation intervention. Am J Prev
Med 1991 7: 95-100.
14.Prochaska JO, DiClemente CC, Velicer W: Personalized computergenerated progress reports for smoking cessation. Unpublished
paper, Kingston, RI; University of Rhode Island, 1988.
15.Tang JL, Law M, Wald N: How effective is nicotine replacement
therapy in helping people to stop smoking? BMJ 1994 308: 21-16.
16.Puska P, Korhonen HJ, Vartioiaimen E, et al: Is combined use of
nicotine patch and gum better than gum alone in smoking cessation? Tobacco Control 1995 4: 231-235.
17.Kornitzer M, Boutsen M, Dramaix M, et al: Combined use of nicotine patch and gum in smoking cessation: a placebo-controlled
clinical trial. Prev Med 1995 24: 41-47.
18.Fagerström KO, Schneider NG, Lunell E: Effectiveness of nicotine
patch and nicotine gum as individual versus combined treatments
for tobacco withdrawal symptoms. Psychopharmacology 1993
111: 271-77.
19.Kottke TE, Solberg LI: Is it not time to make smoking a vital sign?
(editorial). Mayo Clin Proc 1995 70: 303-304.
20.Reid DJ, Killoran AJ, McNeill AD, et al: Choosing the most effective health promotion options for reducing a nation’s smoking
prevalence. Tobacco Control 1992 1: 185-197.
All Therapeutics Letters are also available on our
Web site: http://www.interchange.ubc.ca/jauca/
Tel.:(604) 822•0700
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E-mail: [email protected]
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