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The health effects of smoking, smokeless, and
nicotine
Cardiovascular
disease www.endsmoking.org.nz/cvdeffects.pdf
Summary:
·
Cigarette
smoking: There is strong epidemiological and biochemical
evidence that it increases the risk of heart attack and stroke.
·
Smokeless
tobacco: The evidence for it affecting cardiovascular risk is
disputed. A proven mechanism is lacking.
·
Nicotine:
has a temporary
effect on blood pressure and pulse rate, but extensive follow-up has
shown that nicotine is safe for at least 5 years with respect to mortality
and disease risk.
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Cigarette
smoking
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Cigar
smoking
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Smokeless
tobacco
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Pure
nicotine products
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Risk
of early death
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Cigarette smoking carries a 10-fold
excess sudden-death risk, unmatched by any other coronary risk
factor, and a 3.6 fold excess risk of myocardial infarction.1
The lack of such excess risks with smokeless
or nicotine suggests that smoking’s excess
risk is due to the effect the smoke, rather than to the tobacco or
nicotine.
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For the cigar smokers who inhale, the risk is about equal to
smoking ten cigarettes a day.
Most cigar smokers
do not inhale, and so the
average US
cigar smoker has a risk of dying early from heart disease that is around
90% less than for cigarette smokers.
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Oral tobacco has a disputed effect, if any, on cardio-vascular risk.2 6
It is not known if
smokeless tobacco causes hypertension.
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Nicotine
gum chewed by 3000 participants for 5 years did not increase early
death or hospitalization rates compared with those not using it,
whether they were smokers or not. Dose did not alter this.3
The excess cardiovascular risk of smoking is not due to nicotine.
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Cigarette
smoking
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Smokeless
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Pure Nicotine
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Platelet stickiness.
Thromboxane A2 production by platelets (enhances
platelet stickiness and aggregation; inhibits the continuous
formation of nitric oxide in the lining of blood vessels, which
normally prevent platelets sticking to the lining.4) Yes
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No
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No
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Carbon monoxide In smoke of unfiltered and filtered cigarettes,
cigars and little cigars.5 Present
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Absent
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Absent
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Hydrogen cyanide (HCN) in cigarette
and cigar smoke inhibits cytochrome-c oxidase, blocking the cell from using its oxygen;
the nervous system and the heart are particularly sensitive. In
smoke, HCN is a leading CV toxicant5 7 Present
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Absent.
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Absent
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Myocardial infarction Yes.
Cigarette smoking is a
major cause of myocardial infarction (MI).
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Unclear. Two case-control
studies showed same MI risks as in non-tobacco users. In one cohort
study MI risk increased for CV death.6
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No increased risk from five years intensive use of nicotine
by smokers and nonsmokers.3
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Stroke
Risk is increased by cigarette smoking, and by cigar smokers if they
inhale.5
8
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No increased risk found.9
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No evidence.
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Thickening of CV endothelium on ultrasound Yes
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No
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Not examined.
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Endothelial function in flow-mediated dilatation (FMD)
of the brachial artery reduced after smoking, more so than in non
smokers. 10 11
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FMD effect lowered,
similar to effect of cigarette.11 FMD lowered by a 1g snuff
dose.12
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Nicotine by spray
causes acute endothelial dysfunction, to a lesser extent than a
cigarette.13
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All these products
increase heart rate and blood pressure temporarily – a nicotine
effect.
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1. Kannel WB, McGee DL, Castelli WP. Latest perspectives on cigarette
smoking and cardiovascular disease. The Framingham Study. J Cardiac
Rehabilitation. 1984;4:267.
2. Foulds J, Ramstrom
L, Burke K, Fagerstrom K. Effect of smokeless
tobacco (snus) on smoking and public health in Sweden. Review. Tob Control. 2003;12:349–59.
3 Murray RP, Bailey WC, Daniels K, et al. Safety of nicotine polacrilex gum used by 3,094 participants in the
Lung Health Study. LHS Research Group. Chest. 1996;102:438–45.
4. Wennmalm A. Cardiovascular effects
of cigarette smoke and snuff. In Nicotine Safety and toxicity. (ed. NL Benowitz). Oxford: OUP; 1998.
5 US National Cancer Institute.
Cigars, Health effects and trends. Smoking and Tobacco Control
monograph 9. Bethesda MD. NCI, NIH 1998.
6. Asplund K. Smokeless tobacco and
cardiovascular disease. Prog Cardiovasc Dis 2—3;
45: 383-94.
7. Californian Environmental Protection Agency. Risk assessment
guidelines: chronic reference exposure levels for airborne toxicants.
Office of Environmental Hazard Assessment; 2004.
8. Myint PK, Welch AA, Bingham SA, Luben RN, Wareham NJ, Day NE, Khaw KT. Smoking predicts
long-term mortality in stroke: The European Prospective Investigation
into Cancer (EPIC)-Norfolk prospective population
study.
Prev
Med. 2005 Dec 29; [Epub ahead of print]
9 Asplund K, Nasic
S, Janiert U, Stegmayr
B. Smokeless tobacco as a possible risk factor for stroke in men: a
nested case-control study. Stroke 2003; 34: 1754-9.
10.Esen AM, Barutcu
I, Acar M et al. Effect of smoking on
endothelial function and wall thickness of brachial artery. Circulation
J. 2004; 68: 1123-6.
11. Granberry MC, Smith ES 3rd,
Troillett RD, Eidt
JF. Forearm endothelial
response in smokeless tobacco users compared with cigarette smokers and
nonusers of tobacco. Forearm endothelial response in smokeless tobacco
users compared with cigarette smokers and nonusers of tobacco.
Pharmacotherapy 2003; 23: 974-8.
12. Rohani M, Agewall
S. Oral snuff impairs endothelial function in healthy snuff users. J Intern Med 2004; 255: 379-83.
13. Neunteufl T, Heher S, Kostner
K, et al. Contribution
of nicotine to acute endothelial dysfunction in long-term smokers. J Am
Coll Cardiol 2002;
39: 251-6.
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