Children who had lower respiratory tract infection (LRTI), such as bronchitis or pneumonia, by the age of two were almost twice as likely to die prematurely in adulthood from respiratory diseases.
The study, led by researchers from Imperial College London and published in The Lancet, spans more than 73 years and provides the best evidence to date that early respiratory health has an impact on mortality later in life.
The findings challenge the misconception that adult deaths from respiratory diseases are determined only by behaviour in adulthood, such as smoking.
"Current preventative measures for adult respiratory disease mainly focus on adult lifestyle risk factors such as smoking. Linking one in five adult respiratory deaths to common infections many decades earlier in childhood shows the need to target risk well before adulthood," said lead author Dr James Allinson, from the National Heart & Lung Institute at Imperial.
"The results of our study suggest that efforts to reduce childhood respiratory infections could have an impact on tackling premature mortality from respiratory disease later in life. We hope that this study will help guide the strategies of international health organisations in tackling this issue," added co-author Professor Rebecca Hardy, from University College London and Loughborough University.
The study looked at health and death records for 3,589 people, of which 913 suffered a lower respiratory infection before the age of two.