passive smokers

Background Exposure to second-hand smoke is common in many countries but the magnitude of the problem
worldwide is poorly described. We aimed to estimate the worldwide exposure to second-hand smoke and its burden
of disease in children and adult non-smokers in 2004.
Methods The burden of disease from second-hand smoke was estimated as deaths and disability-adjusted life-years
(DALYs) for children and adult non-smokers. The calculations were based on disease-specific relative risk estimates
and area-specific estimates of the proportion of people exposed to second-hand smoke, by comparative risk assessment
methods, with data from 192 countries during 2004.
Findings Worldwide, 40% of children, 33% of male non-smokers, and 35% of female non-smokers were exposed to
second-hand smoke in 2004. This exposure was estimated to have caused 379 000 deaths from ischaemic heart
disease, 165 000 from lower respiratory infections, 36 900 from asthma, and 21 400 from lung cancer. 603 000 deaths
were attributable to second-hand smoke in 2004, which was about 1·0% of worldwide mortality. 47% of deaths from
second-hand smoke occurred in women, 28% in children, and 26% in men. DALYs lost because of exposure to secondhand
smoke amounted to 10·9 million, which was about 0·7% of total worldwide burden of diseases in DALYs in
2004. 61% of DALYs were in children. The largest disease burdens were from lower respiratory infections in children
younger than 5 years (5 939 000), ischaemic heart disease in adults (2 836 000), and asthma in adults (1 246 000) and
children (651 000).
Interpretation These estimates of worldwide burden of disease attributable to second-hand smoke suggest that
substantial health gains could be made by extending effective public health and clinical interventions to reduce passive
smoking worldwide.