Lifetime environmental tobacco smoke exposure and the risk of chronic obstructive pulmonary disease

BACKGROUND: Exposure to environmental tobacco smoke (ETS), which contains potent respiratory irritants, may lead to chronic airway inflammation and obstruction. Although ETS exposure appears to cause asthma in children and adults, its role in causing COPD has received limited attention in epidemiologic studies. METHODS: Using data from a population-based sample of 2,113 U.S. adults aged 55 to 75 years, we examined the association between lifetime ETS exposure and the risk of developing COPD. Participants were recruited from all 48 contiguous U.S. states by random digit dialing. Lifetime ETS exposure was ascertained by structured telephone interview. We used a standard epidemiologic approach to define COPD based on a self-reported physician diagnosis of chronic bronchitis, emphysema, or COPD. RESULTS: Higher cumulative lifetime home and work exposure were associated with a greater risk of COPD. The highest quartile of lifetime home ETS exposure was associated with a greater risk of COPD, controlling for age, sex, race, personal smoking history, educational attainment, marital status, and occupational exposure to vapors, gas, dusts, or fumes during the longest held job (OR 1.55; 95% CI 1.09 to 2.21). The highest quartile of lifetime workplace ETS exposure was also related to a greater risk of COPD (OR 1.36; 95% CI 1.002 to 1.84). The population attributable fraction was 11% for the highest quartile of home ETS exposure and 7% for work exposure. CONCLUSION: ETS exposure may be an important cause of COPD. Consequently, public policies aimed at preventing public smoking may reduce the burden of COPD-related death and disability, both by reducing direct smoking and ETS exposure

Adult onset asthma and interaction between genes and active tobacco smoking: The GABRIEL consortium.

BACKGROUND: Genome-wide association studies have identified novel genetic associations for asthma, but without taking into account the role of active tobacco smoking. This study aimed to identify novel genes that interact with ever active tobacco smoking in adult onset asthma. METHODS: We performed a genome-wide interaction analysis in six studies participating in the GABRIEL consortium following two meta-analyses approaches based on 1) the overall interaction effect and 2) the genetic effect in subjects with and without smoking exposure. We performed a discovery meta-analysis including 4,057 subjects of European descent and replicated our findings in an independent cohort (LifeLines Cohort Study), including 12,475 subjects. RESULTS: First approach: 50 SNPs were selected based on an overall interaction effect at p<10-4. The most pronounced interaction effect was observed for rs9969775 on chromosome 9 (discovery meta-analysis: ORint = 0.50, p = 7.63*10-5, replication: ORint = 0.65, p = 0.02). Second approach: 35 SNPs were selected based on the overall genetic effect in exposed subjects (p <10-4). The most pronounced genetic effect was observed for rs5011804 on chromosome 12 (discovery meta-analysis ORint = 1.50, p = 1.21*10-4; replication: ORint = 1.40, p = 0.03). CONCLUSIONS: Using two genome-wide interaction approaches, we identified novel polymorphisms in non-annotated intergenic regions on chromosomes 9 and 12, that showed suggestive evidence for interaction with active tobacco smoking in the onset of adult asthma

Mouse models to unravel the role of inhaled pollutants on allergic sensitization and airway inflammation

Air pollutant exposure has been linked to a rise in wheezing illnesses. Clinical data highlight that exposure to mainstream tobacco smoke (MS) and environmental tobacco smoke (ETS) as well as exposure to diesel exhaust particles (DEP) could promote allergic sensitization or aggravate symptoms of asthma, suggesting a role for these inhaled pollutants in the pathogenesis of asthma. Mouse models are a valuable tool to study the potential effects of these pollutants in the pathogenesis of asthma, with the opportunity to investigate their impact during processes leading to sensitization, acute inflammation and chronic disease. Mice allow us to perform mechanistic studies and to evaluate the importance of specific cell types in asthma pathogenesis. In this review, the major clinical effects of tobacco smoke and diesel exhaust exposure regarding to asthma development and progression are described. Clinical data are compared with findings from murine models of asthma and inhalable pollutant exposure. Moreover, the potential mechanisms by which both pollutants could aggravate asthma are discussed

Distribution of total serum IgE and specific IgE to common aeroallergens by sex and age, and their relationship to each other in a random sample of the Dutch general population aged 20-70 years

To describe the distribution of serum total IgE and specific IgE to common aeroallergens by sex and age and to study their relationship to each other, we measured serum total IgE and specific IgE (CAP) to house-dust mile, timothy grass, cat, birch, and Cladosporium in a random sample of 2496 subjects, aged 20-70 years from the Dutch general population. We found that total IgE was higher in men, independently of smoking, and that total IgE had no relationship with age after adjustment for specific IgE and smoking in linear regression analysis. Al least one positive specific IgE test was found in 32% in both sexes. Men had higher prevalences of specific IgE to house-dust mite and lower prevalences of specific IgE to birch than women. The proportion with positive specific IgE decreased with age. The mean total IgE increased with the number of positive specific IgE tests, Thus, total IgE is higher in men and has no relationship with age if specific IgE is taken into account. The prevalences of specific IgE to aeroallergens are high and decrease with increasing age, We suggest that sex differences in total IgE should be considered when using total IgE

Increased prevalence of asthma and allied diseases among active adolescent tobacco smokers after controlling for passive smoking exposure. A cause for concern?

International audienceBACKGROUND: Whereas effects on allergic and respiratory health have been established for passive tobacco smoking, contradictory results still exist for active tobacco smoking. OBJECTIVE: Whether adolescents with asthma and allied diseases have higher rates of active smoking compared with adolescents without asthma was assessed after controlling for environmental tobacco smoking exposure. METHODS: A population-based sample of 14,578 adolescents was enrolled in an epidemiological survey on allergies in France. RESULTS: After controlling for age, sex, geographic region, familial allergy and passive smoking, current (in the past year) wheezing (12.4%), current asthma (5.6%), lifetime asthma (12.3%), current rhinoconjunctivitis (13.9%), lifetime hayfever (14.4%) and current eczema (9.3%) but not lifetime eczema (22.5%) were all significantly related to active smoking (>1 cigarette/day) (9.3%). A higher risk of current wheezing, current and lifetime asthma or current eczema was seen in smokers exposed to passive smoking compared with smokers not exposed to it using a polychotomous logistic regression model, in which the different modalities of exposure to active and passive smoking constituted the response variable. Passive smoking was significantly associated only with current diseases. Active smoking was also highly related to both severe asthma (OR=4.02; 95% confidence interval: 1.37, 11.79) and severe rhinoconjunctivitis (OR=2.95; 1.58, 5.49). The highest rate of adolescents suffering from the co-morbidity of lifetime asthma and hayfever (3.6%) was also seen in active smokers compared with passive and non-smokers (5.5% vs. 3.6% and 3.1%, respectively; P=0.001). CONCLUSIONS: Being asthmatic or allergic does not seem to act as a deterrent towards starting active smoking or continuing to smoke in adolescence. Results suggest the need for considering individual allergic status in programming health educational activities aimed at reducing smoking among adolescents