Earlier this winter, experts warned of a “tridemic” as the 2022-2023 viral season started, with COVID-19 still around, influenza season starting, and an unexpected surge in respiratory syncytial virus (RSV). In fact, in November 2022, RSV hospitalizations climbed to a high of 4.9 per 100,000 patients—a sharp rise from the November 2021 hospitalization rate of 1.1 per 100,000 and pre-pandemic rates of roughly 0.5 per 100,000.
While RSV cases have started to decline, researchers at Imperial College London recently discovered another piece of the puzzle—and it’s not good. According to their new research, contracting a lower respiratory tract infection in early childhood is associated with a higher risk of dying from respiratory disease as an adult.
In the study published in The Lancet, the researchers showed the rate of premature death from respiratory disease was about 2% for those who had a lower respiratory tract infection (LRTI) in early childhood, compared with around 1% for those who did not.
Previous research has linked infant LRTIs to the development of adult lung function impairments, asthma and COPD, but it has been unclear if there is also a link to premature death in adulthood. This first-of-its-kind study 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 research team, led by James Peter Allinson, used data from 3,589 people part of the National Survey of Health and Development. Understanding the importance of whole-of-life studies, the survey recruited individuals at birth in 1946, continuing to examine their health and death records up to 2019. Of the 3,589 participants, 913 suffered a lower respiratory infection before the age of two.
For the purposes of the new study, the researchers used a statistical model to estimate the association between a respiratory infection in early childhood and premature death from respiratory diseases in adulthood, while adjusting for different factors that can influence risk.
Analysis adjusting for socioeconomic background during childhood and smoking status suggested that children who had a LRTI by the age of two were 93% more likely to die prematurely from respiratory disease as adults, compared with children who did not have a LRTI by age two. This equates to a 2.1% rate of premature adult death from respiratory disease among those who had a LRTI in early childhood, compared with 1.1% among those who did not report a LRTI before the age of two.
The researchers say this increased risk potentially accounts for 179,188 premature deaths in England and Wales between 1972 and 2019—or one in five deaths from respiratory disease.
The team says their findings challenge the misconception that adult deaths from respiratory diseases are determined only by behavior.
“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 Allinson.
Additionally, the findings very obviously demonstrate the importance of optimizing childhood health, from basic vaccines to addressing childhood poverty with targeted public health measures and health service interventions.
“If early childhood LRTIs are causally linked to premature adult respiratory-cause mortality, preventing these infections or possibly lessening infection severity might offer an earlier interventional opportunity,” the authors write. “Identifying young children with LRTIs and actively optimizing their health as they and their lungs grow into adulthood might be one way to break the connection between poor respiratory health in childhood and adulthood. [Additionally,] addressing childhood poverty worldwide could help avoid the perpetuation of health inequities across life, down generations and between communities.”