Children exposed to tobacco smoke show early adult emphysema
A new study shows that children who are exposed to tobacco smoke at home face early emphysema in adulthood. The findings suggest children’s lungs do not recover from exposure to tobacco smoke, making smoking cessation an important goal for family and parents with young children – not to mention the personal health gains found from discontinuing smoking.
The findings come from researchers at Columbia University's Mailman School of Public Health, showing that early-life exposures to tobacco smoke (ETS) damages the lungs of children permanently. The study is published in the December 2009 American Journal of Epidemiology, and was also presented May 2009 at the International Conference of the American Thoracic Society.
The study is the first to look at lung changesin adults who do not smoke. Lung changes seen on CT scan, associated with exposure to tobacco smoke during childhood were worse for adults whose households had two smokers, compared to one, and again compared to no one who smoked at home.
"We were able to detect a difference on CT scans between the lungs of participants who lived with a smoker as a child and those who did not," observed Gina Lovasi, PhD, MPH, assistant professor of epidemiology at Columbia's Mailman School of Public Health. "Some known harmful effects of tobacco smoke are short term, and this new research suggests that effects of tobacco smoke on the lungs may also persist for decades." Given the findings, protecting children from tobacco smoke becomes an issue that goes beyond personal choices related to health.
Non-smokers were recruited for the research that included 1781 healthy non smoking adults from six communities in the United States, including northern Manhattan and the Bronx, New York. Individuals reporting childhood exposure to tobacco smoke were average age 61, primarily non- Hispanic white; and less likely to have been born outside the United States, all factors that were statistically accounted for in the study.
Though changes indicating emphysema were found on CT scan in the adults studied who were exposed to tobacco smoke in childhood, there was no evidence of decline in lung function. However the researchers say "emphysema may be a more sensitive measure of damage compared with lung function in this relatively healthy cohort." There was no information in the study that could tell the researchers if lung damage occurs during pregnancy from expectant mothers who smoke. "The association between childhood ETS and early emphysema among participants whose mothers did not smoke, suggests that the effect we are detecting is for smoke exposure in the home during childhood rather than in utero exposure alone.”
Children exposed to tobacco smoke at home are also at increased risk for asthma. Reducing indoor allergens that include dust mites, cockroaches, and tobacco smoke can improve the health in adulthood by reducing inflammation and damage to small sensitive airways during childhood. The new study is the first to show that emphysema occurring in early adulthood is linked to exposure to tobacco smoke during childhood, and that the damage is permanent.
American Journal of Epidemiology, December 2009