A father’s lifelong exposure to passive smoking from his parent could affect his own children’s lungs and put them at risk of chronic respiratory conditions, a new study found.
The study, published in the journal Thorax, highlights the intergenerational harms of smoking and urges fathers to cut this harmful cycle in its tracks by avoiding smoking around their children.
Researchers from the University of Melbourne say the risk of getting chronic obstructive pulmonary disease, commonly known as COPD, is elevated if the grandchildren are passive smokers themselves.
COPD, which includes conditions such as chronic bronchitis and emphysema, is the third leading cause of death around the world, killing around 3 million people every year.
Previous research suggests that factors like smoking increase the risk of poor lung function and resultant COPD.
Though passive smoking during a father’s childhood was known to be linked to a heightened risk of asthma in his children by their 7th birthday, it was not clear if the harm to their lungs extended into middle age and beyond.
The University of Melbourne researchers used spirometry to assess the lung function of more than 8,000 children who were part of the Tasmanian Longitudinal Health Study.
They also had the parents of the participants complete a comprehensive survey about their own and their children’s respiratory health.
Then, the researchers did follow-up assessments when the children were 13, 18, 43, 50 and 53, looking at two common measures of lung function.
Of the nearly 7,250 parents who were alive and could be located in 2010, about 5,000 were re-surveyed about whether their own parents had smoked when they were under the age of 5 and/or up to when they were 15.
The final assessment included data on a father’s passive smoke exposure before puberty and lung function data for their children up to the age of 53.
Over two-thirds of the fathers and more than half of their children had been exposed to passive smoking during childhood. About half of the children had a history of active smoking by middle age and just over 5 per cent had developed COPD by this time, as assessed by spirometry.
The findings suggest a father’s exposure to passive smoking as a child is associated with more than 50 per cent higher odds of “below average” lung performance in his children across their lifespan.
The researchers say this link is “statistically significant” even after adjusting for other factors. “Our findings are novel as this is the first study to investigate and provide evidence for an adverse association of paternal prepubertal passive smoke exposure rather than just active smoking on impaired lung function of offspring by middle age,” they say.
“These findings suggest that smoking may adversely affect lung function not only in smokers but also in their children and grandchildren. Fathers exposed to tobacco smoke during prepuberty may still reduce risk for future generations by avoiding smoking around their children.”
