Scarring of the lungs, or pulmonary fibrosis, is one of the most dreaded diseases in pulmonary medicine. In this illness, the lungs become scarred from a variety of causes, including occupational exposures, your own immune system, medications, and more. In many cases, we do not know what has caused the scarring, and these patients often get worse and come into the hospital very sick. I have had many die in my ICU, and it is a helpless feeling when I am unable to tell them or their family why they have gotten worse, what is causing their disease, and most devastatingly, why they are dying.
We know that air pollution is deadly. As I always say, inhaling particulate matter, especially PM2.5 in the air, causes similar diseases as smoking cigarettes. We know that a history of smoking is a risk factor for some forms of pulmonary fibrosis. We know PM2.5 exposure causes lung cancer and increases the risk of coronary artery disease, heart attacks, strokes and more. For example, in one study of Medicare beneficiaries, there was an increase in death from all causes with exposure to PM2.5.
A history of smoking cigarettes increases the risk for idiopathic pulmonary fibrosis, which is one of the most dreaded types of lung scarring. “Idiopathic” means we often don’t know what causes it or makes it worse. I wanted to discuss this with a researcher who is trying to understand the potential impact of air pollution on patients with pulmonary fibrosis.
I was fortunate to speak with Dr. Gillian Goobie of the Center for Heart Lung Innovation at St Paul’s Hospital in Vancouver as well as the Division of Respiratory Medicine at the University of British Columbia. She obtained her MD and completed residency in internal medicine at the University of Calgary and her respiratory medicine fellowship at the University of British Columbia. She obtained her PhD in Human Genetics at the University of Pittsburgh. She studies pulmonary fibrosis and how air pollution impacts the disease. She also serves with me on the Environmental Health Policy Committee of the American Thoracic Society.
She is the lead author on a groundbreaking paper exploring the risk of death from exposure to air pollution. In this study, they look at different groups of patients with pulmonary fibrosis and whether they were exposed to high levels of PM2.5 (above the ATS recommended limit of 8 ug/m3) or below. If they were, the increased risk of death was significant. You can see one of the more dramatic death rate risks in the figure below.
They also looked into what was in the actual pollution, breaking it down by anthropogenic, that is, caused by human activity, such as industry, air pollution, etc vs other sources of PM2.5. They found that there was an increased risk of death when pollution from industrial sources was a main component of the PM2.5.
It was a pleasure to talk to Dr. Goobie on the podcast. I have seen her testify about the impact of air pollution on her patients to the EPA, and she is a model of a physician-scientist focused not only on caring for the patient in front of her, but helping us understand more about the disease from which they are suffering and how we might prevent it. In her interview, she expressed gratitude to her patients and their important contribution to the work by participating in research in their own illness. Science is truly a community effort, and the work of the people who participate in studies is vitally important.
I am also grateful to my own patients, who every day inspire me to continue exploring the links between the air we breathe and how it turns people into patients. Why does the presumed healthy, non-smoking patient end up in my ICU with a heart attack? Why does the patient with pulmonary fibrosis deteriorate and end up on a ventilator, and how do I talk to their family about why that has happened, our limited treatment options, and whether we should keep going? If there is a chance that we can prevent those deteriorations and deaths by cleaning up the air for all of us, it is vital that we as physicians and communities advocate for that.
I serve on the Environmental Health Policy Committee of the American Thoracic Society, and the ATS has been advocating strongly to the EPA to lower the mean PM2.5 standard from 12ug/m/3 to 8 ug/m/3. I hope this more protective standard is set, and I hope we can clean up the air in our communities, for the sake of all of us, and especially patients with pulmonary fibrosis.
So what can you do?
1- Download the AirNow.gov app and become familiar with it.
2- To learn more about PM2.5 standards and history, listen to the “What’s in a Standard” episode with Dan Costa from Season Two.
3- For more on how to use the Air Quality Index, listen to the “What’s in an Index” episode with Dr. Franziska Rosser from last season.
4- For those in the West, particularly affected by PM2.5 and wildfire smoke, listen to the “Our Health in Wildfire Season” episode from Season Two and the “Air Inside when the smoke is outside” episode with Prof Elliot Gall from Season One.
5- Finally, consider a donation to the American Thoracic Society, whose scientific membership includes clinician-scientists like Dr. Goobie who do such important research and work hard to highlight the importance of clean air.
