Cystic fibrosis is a genetic disorder that triggers the mucous membranes of an afflicted person to produce a clotted mucus that can damage the body’s organs, including the:

• lungs (the primary organ affected)
• digestive tract
• pancreas
• liver

The complications from this disease include blockages, infections, and inflammation to the affected areas. In the lungs, the thick mucus clogs the airways, increases the risks of illnesses such as pneumonia and bronchitis, and can ultimately result in respiratory failure (1).

It’s no surprise, then, that cystic fibrosis sufferers are particularly vulnerable to the harmful effects of pollutants in the air.

Read on to find out about the size and scope of the impact that air pollution has on people with cystic fibrosis.

Early research

In 2004, researchers at the University of Washington sought to quantify air pollution’s impact to people with cystic fibrosis. The study referenced 11,484 people listed in the Cystic Fibrosis Foundation’s national patient registry and compared with air pollution data collected from monitoring stations across the country (2).

The study looked at individual patient’s lung function measurements, and their medical treatment needs with the concentration of pollution particulates measured in that individual’s community, averaged over a year’s time.

The results found a direct correlation between higher levels of exposure to air pollution such as ozone, nitrogen dioxide, and:

• decreased levels of lung functioning
• increased cases of lung infections
• a 21% greater risk of having to undergo a course of intravenous antibiotics to treat infections

Air pollution and children with cystic fibrosis

Another study, conducted in 2017, assessed infection increased risk in children, based on the amount of increased exposure to air pollution (3).

The subjects in the study were cystic fibrosis-afflicted children under the age of six.

Researchers calculated that an increased exposure of 10 micrograms per cubic meter (μg/m3) of PM2.5 (pollution particles that measure 2.5 microns in diameter or smaller) led to a 68% rise in the risk of developing methicillin resistant Staphylococcus aureus (MRSA), an infection that is caused by bacteria that is resistant to antibiotics.

A 2015 study with a similar group of subjects looked for an association between the age the subjects were first detected with Pseudomonas aeruginosa, a bacteria that causes pneumonia and infections in the blood and other parts of the body, and the subjects’ exposures to air pollution (4).

Pseudomonas aeruginosa are commonly found in nature, especially in moist environments, and seldom cause disease in healthy people (5) (6). But individuals with cystic fibrosis are more at peril of ill health when they come into contact with the bacteria (7).

The study found that an increased exposure of 10 μg/m3 of PM2.5 resulted in a 24% greater risk of children with cystic fibrosis first acquiring the bacteria at a younger age.

A separate study of infants with cystic fibrosis showed those detected with Pseudomonas aeruginosa before six months of age risk a greater decline in lung function by preschool age than those detected with the bacteria after six months of age (8).

Short-term impacts of air pollution on cystic fibrosis patients

Pulmonary exacerbations, common occurrences in cystic fibrosis patients that often must be treated with oral or IV antibiotics, are associated with (9):

• intensified coughing
• increased sputum production
• shortness of breath
• acute decrease of lung function

Research in 2013 evaluated whether a rise in air pollution levels had an immediate effect on pulmonary exacerbations (10).

The study matched an individual patient’s event, defined by that patient starting an antibiotic treatment, with local levels of air pollution on the day of the event and the two days prior.

After analyzing the data, a clear association was found between a patient’s pulmonary exacerbation and an increase of airborne nitrogen dioxide, ozone, and PM10 (pollution particles that measure 10 microns in diameter or smaller) on the day of the event.

There was also a correlation to a rise in PM10 and ozone on the day previous to the day of the pulmonary exacerbation.

The impact of indoor air pollution on cystic fibrosis

In 2022, a study sought to add to the limited data on how indoor air pollution affects people with cystic fibrosis (11).

An evaluation was made of the data from patients in a separate study, the Twin and Sibling Study, who self-reported their exposure to four sources of easily identified indoor sources of air pollution:

• secondhand smoke
• forced hot air
• smoke from woodstoves
• smoke from fireplaces

For four years, lung function, hospitalization rates, and number of pulmonary exacerbations were tracked for participants of the study who were exposed to one or more of the designated sources of indoor air pollution and those who were not.

Lung function was calculated from the scores of the patients’ FEV1 (forced expiratory volume) tests, which measure the amount of air a person can force from their lungs in one second.

Children in the study suffered a 0.46% yearly decrease in lung function when exposed to forced hot air compared to those who were not exposed, and a 0.60% yearly decrease when exposed to secondhand smoke.

The results also included a 46% greater chance of hospitalization in adult cystic fibrosis patients who were exposed to secondhand smoke than those who were not.

The takeaway

Exposure to air pollution cannot cause cystic fibrosis. The illness is inherited at birth by receiving a mutated cystic fibrosis transmembrane conductance regulator (CFTR) gene from both parents.

But exposure to air pollution can extremely worsen the symptoms of cystic fibrosis and ultimately, shorten the lifespan of a cystic fibrosis patient who already faces a compromised future.

To help improve the quality of life for people with cystic fibrosis, the medical community is making every effort towards:

• better identification of the disease, especially in children
• the development of new therapies
• the establishment of intensified, targeted therapies
• further studies with air quality assessments to better understand the impact of indoor and outdoor air pollution on cystic fibrosis
• more research on other non-genetic contributing factors

To help protect you or your loved ones with cystic fibrosis from the harmful effects of air pollution:

• monitor your indoor and outdoor air quality, and set up alerts to notify you to unhealthy air
• use high performance room air purifiers to keep the air indoors free from pollutants
• use a portable desk air purifier to keep your personal breathing space healthy
• install a car air purifier for healthier travel
• follow an air quality monitoring index to know the outdoor air you breathe wherever you go
• wear a mask when air quality is unhealthy

And we can all reduce our personal air pollution outputs and advocate for clean air laws to help improve the health of everyone.