Legislative smoking bans for reducing secondhand smoke exposure ...

Main results
There were 50 studies included in this review. Thirty-one studies reported exposure to secondhand smoke (SHS) with 19 studies
measuring it using biomarkers. There was consistent evidence that smoking bans reduced exposure to SHS in workplaces, restaurants,
pubs and in public places. There was a greater reduction in exposure to SHS in hospitality workers compared to the general population.
We failed to detect any difference in self-reported exposure to SHS in cars. There was no change in either the prevalence or duration
of reported exposure to SHS in the home as a result of implementing legislative bans. Twenty-three studies reported measures of active
smoking, often as a co-variable rather than an end-point in itself, with no consistent evidence of a reduction in smoking prevalence
attributable to the ban. Total tobacco consumption was reduced in studies where prevalence declined. Twenty-five studies reported health
indicators as an outcome. Self-reported respiratory and sensory symptoms were measured in 12 studies, with lung function measured
in five of them. There was consistent evidence of a reduction in hospital admissions for cardiac events as well as an improvement in
some health indicators after the ban.
Authors’ conclusions
Introduction of a legislative smoking ban does lead to a reduction in exposure to passive smoking. Hospitality workers experienced
a greater reduction in exposure to SHS after implementing the ban compared to the general population. There is limited evidence
about the impact on active smoking but the trend is downwards. There is some evidence of an improvement in health outcomes. The
strongest evidence is the reduction seen in admissions for acute coronary syndrome. There is an increase in support for and compliance
with smoking bans after the legislation.
P L A I N L A N G U A G E S U M M A R Y
Does legislation to ban smoking reduce exposure to secondhand smoke and smoking behaviour?
There has been an increase in the number of countries and states implementing smoking policies which ban or restrict smoking in
public places and workplaces. The main reason is to protect nonsmokers from the harmful health effects of exposure to secondhand
smoke. Another reason is to provide a supportive environment for people who want to quit smoking. Fifty studies were included in this
review. Legislative bans reduced exposure to secondhand smoke. There was no change in exposure to secondhand smoke in private cars
after implementing legislative smoking bans. There was no change in self-reported SHS exposure in the home. There are fewer data
measuring smoking prevalence and smoking behaviour with either no change or a downward trend reported. There is some evidence
that the health of those affected by the smoking ban improved as a result of its implementation, most impressively in relation to heart
attacks in hospitals.
B A C K G R O U N D
Tobacco is the second major cause of mortality in the world, and
currently responsible for the death of about one in ten adults
worldwide (WHO 2005). Measures to control the demand for
and supply of tobacco products, as well as to protect public health,
have been highlighted further through the Framework Convention
on Tobacco Control (WHO 2003). In setting the parameters
for this systematic review, we take a strict methodological
approach in keeping with the Cochrane process but we have to
consider the nature of health promotion interventions in setting
those parameters.
Since the publication of the Surgeons General’s Report in 1986
(WHO 1986), there has been an increase in the number of smok-
ing bans and restrictions. The US Surgeon General’s Report and
the National Research Council declared secondhand smoke to be
a cause of lung cancer in healthy nonsmokers (DHHS 1986; NRC
1986). Secondhand smoke, also known as environmental tobacco
smoke (ETS) or passive smoke, is the combination of side-stream
smoke, i.e. smoke that is emitted between puffs of burning tobacco
(cigarettes, pipes or cigars), and mainstream smoke, i.e. smoke
that is exhaled by the smoker (NCI 1999). Secondhand smoke is
a complex mixture of thousands of gases and particulate matter
emitted by the combustion of tobacco products and from smoke
exhaled by those smoking (NRC 1986). Secondhand smoke was
declared to be carcinogenic by the International Agency for Research
on Cancer (IARC 2002; IARC 2004).
Legislative smoking bans for reducing secondhand smoke exposure, smoking prevalence and tobacco consumption (Review)
Copyright © 2010 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.
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