Background: Exposure to second-hand smoke (SHS) is an exposure to air pollution of fine particulate
matter, carcinogens, and various toxins, affecting large parts of the population.
SHS increases the risk for acute cardiovascular events and may contribute to the development
of atherosclerosis. We investigate the association of SHS with coronary artery calcification
(CAC). Methods: In the present cross-sectional analysis, we used baseline data (2000–2003) of 1,891
never smokers, aged 45 to 75 years, from an ongoing, prospective, population-based
cohort study in Germany. Frequent SHS at home, at work and in other places was assessed
by questionnaire. CAC was measured by electron-beam computed tomography. We conducted
multiple linear regression analysis using exposure to SHS (any location) as the explanatory
variable and ln(CAC+1) as the response variable, adjusting for gender, age, socio-economic
status, and cardiovascular risk factors. Results: Frequent exposure to SHS was reported by 21.7% of respondents. After adjustment for
age, gender, and socio-economic status, (CAC +1) was 25.9% (95% CI: –1.0 to 60.2%)
higher in the exposed than in the unexposed. Inclusion of further cardiovascular risk
factors (diabetes, cholesterol, body mass index, physical activity) reduced the estimate
(19.7%; 95% CI: –5.4 to 51.5%). Highest effects were seen for exposure at home (35.8%;
95% CI –2.8 to 89.8%). The effect of SHS was comparable to up to 3 years of older
vascular age, depending on age-range and sex. Conclusions: Our study provides first suggestive evidence of an association between exposure to
SHS and coronary atherosclerosis. Considering the widespread exposure and the clinical
relevance of coronary atherosclerosis, this result, if confirmed, is likely to be
of high public health importance.
