Most cases of chronic obstructive pulmonary disease (COPD) can be linked to factors in childhood, according to a major new study, which highlights the need for early intervention and prevention.
While smoking remains the biggest risk factor for COPD, the study shows childhood illnesses and exposure to parental smoking are also linked to the disease and can set people on a course to poor lung function in later life.
“These findings highlight the importance of preventing both early life adverse exposures and adult risk factors”
The research – published in The Lancet Respiratory Medicine – found three quarters of COPD cases were associated with early illness such as asthma, bronchitis, pneumonia and eczema and exposure to second-hand smoke that could all hamper lung growth.
When combined with factors in adulthood – such as taking up smoking – this increased the chances of rapid deterioration of the lungs, leading to COPD.
The study, by researchers in Australia, tracked more than 2,400 participants in a long-term health study from childhood to the age of 53.
Lung function was measured at the ages of seven, 13, 18, 45, 50 and 53, and exposure to various risk factors was also recorded.
The researchers identified six distinct trajectories, or “pathways”, to describe how lung function changed with age.
Three of these were associated with COPD – below average lung function in early life with a quick decline in lung function in later life, persistently low lung function, and below average lung function.
These were linked to three quarters of all cases of COPD at the age of 53 among the study group. Meanwhile, all cases of moderate to severe COPD arose from the three pathways.
“COPD is expected to be the third largest cause of death globally by 2030”
The three trajectories were also linked to childhood asthma, bronchitis, pneumonia, allergic rhinitis, eczema, parents having asthma or smoking, and the participants themselves having asthma in adulthood and smoking.
“These findings highlight the importance of preventing both early life adverse exposures that could lead to poorer lung growth, and adult risk factors contributing to accelerated lung decline,” said study author Professor Shyamali Dharmage, from the University of Melbourne.
“COPD is expected to be the third largest cause of death globally by 2030, and it is important that we identify its key causes so that this burden can be reduced,” she said.
Steps to reduce smoking among parents – and more generally – promote immunisation, and ensure people with asthma get appropriate treatment were key in minimising the risk of COPD, she added.
Meanwhile, a separate study in the same journal – by researchers from the UK and Australia – suggested there was a window of opportunity in childhood to reduce the risk of poor lung function in later life.
This study, which involved the University of Bristol, tracked the lung function of more than 2,600 participants from birth to 24.
Crucially the study found the majority – around 75% – of babies who had poor lung function at one to six months saw it improve throughout childhood.
The researchers said their findings suggested there were opportunities to intervene at this early stage to maximise lung growth and help prevent COPD later on.