Three-quarters of chronic obstructive pulmonary disease (COPD) cases have their origins in poor lung function pathways beginning in childhood. These pathways are associated with exposures in childhood, and amplified by factors in adulthood, according to a cohort study published in The Lancet Respiratory Medicine journal.

While smoking remains the biggest risk factor for COPD, the study demonstrates that childhood illnesses (such as asthma, bronchitis, pneumonia, allergic rhinitis, eczema) and exposures to parental smoking are also linked to the disease. "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. 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," says study author Professor Shyamali Dharmage, School of Population and Global Health, The University of Melbourne, Australia.