Chronic obstructive pulmonary disease (COPD) is a progressive lung disease and the third leading cause of death in the US. It is almost exclusively diagnosed in adults over 40 years old and the main cause is smoking.
As a pediatric pulmonologist, I don’t diagnose much COPD, but I do see a lot of pneumonia. This made me wonder, are children with pneumonia at increased risk for future lung disease from smoking? Is there a group of COPD patients where the first signs of future disease are in childhood?
The relationship between childhood pneumonia and COPD
In the recent Respiratory Research publication, Childhood pneumonia increases risk for chronic obstructive pulmonary disease: the COPDGene study, I examined if adult smokers who had pneumonia in childhood were at increased risk for COPD and decreased lung function.
Are children with pneumonia at increased risk for future lung disease from smoking?
Working with a large group of researchers we studied 10,000 current and former adult smokers across the US ages 45-80. Since we could not get participants’ medical records from over 50 years ago, our surveys asked the adult study subjects if they had an episode of pneumonia when they were younger than 16 years old.
We also asked about asthma in childhood. We compared adult smokers with a history of pneumonia in childhood to those without, looking at diagnosis with COPD, lung function tests, and disease on chest computed tomography (CT) scans.
We found that, in adult smokers, having had childhood pneumonia was associated with a higher risk of COPD, decreased lung function, and increased disease of the airways on chest CT scans. The greatest association with COPD was seen in subjects who had both pneumonia and asthma during childhood. This research supported our hypothesis: there is an association between having pneumonia as a child and increased risk for COPD as an adult if you are a smoker.
Looking to the future
These results suggest that medical providers have a chance to decrease the risk of future COPD by trying to prevent childhood pneumonias, especially among asthmatics. We can also counsel patients who have pneumonia in childhood about an increased risk for COPD if they start smoking. This is especially relevant for pediatric medical providers as 1 out of 15 high school seniors report daily cigarette use.
1 out of 15 high school seniors report daily cigarette use.
My next step is to try and identify genetic associations that could define subtypes of COPD that originate with childhood respiratory disease. This is a particularly interesting investigation as it could answer a much larger question: why do some children have an increased risk for lung disease?
I hope that in the future we will be able to use a patient’s genetic risk to better understand who will develop lung diseases such as asthma and COPD, how their lung disease will progress, and the best ways to both prevent disease and treat each individual patient.