Long-term exposure to those inhaled irritants can affect the respiratory system in different ways. When those irritants affect the airways it causes chronic bronchitis, and when they damage the air sacs in the lungs it leads to emphysema, but both of those conditions would be under the general umbrella of COPD, according to Philip Diaz, MD, a pulmonologist and critical care doctor at the Ohio State University Wexner Medical Center in Columbus.
Smoking and Chronic Bronchitis
Chronic bronchitis occurs when the bronchial tubes — airways that bring air to and from your lungs — are constantly irritated and inflamed. Cigarette smoke contains thousands of chemical components. When you breathe in cigarette smoke, the chemicals irritate and activate certain white blood cells (macrophages) and cells that make up the lining of the airways (epithelial cells). The persistent airway inflammation caused by cigarette smoke can cause a cycle of injury and repair that changes the structure of the airways and makes them narrower. Cigarette smoke also induces a cascading effect that results in certain cells producing more mucus (also called sputum) than normal. What’s more, the irritants decrease the number and length of cilia — hair-like structures that beat rapidly to move particles, fluid, and mucus through your airways. With the cilia unable to do their jobs, mucus blankets the lining of the airways, providing a home for bacteria, which can release toxins that promote mucus production and further damage cilia.
Smoking and Emphysema
Emphysema occurs when alveoli — air sacs located at the end of the bronchial tubes in grape-like clusters — become damaged. “This also affects airflow because the lungs lose their elasticity, which results in labored breathing,” says Dr. Diaz. The lungs should work more like a balloon, nice and elastic: You blow up the balloon and then let it go, and the air comes out nice and fast, says Diaz. “When a person has emphysema, their lungs function more like a paper bag — there’s no elasticity and it’s harder to get the air out,” he says. Cigarette-smoke-induced inflammation is thought to be an underlying cause of emphysema, but the processes involved are unclear. Some research suggests that certain inflammatory cells release enzymes that break down the proteins responsible for alveolar elasticity. Cigarette smoke may also somehow induce programmed cell death (apoptosis) in alveolar cells.
How Quickly Does Cigarette Smoking Cause Lung Damage?
“Usually, people aren’t getting COPD until they’re in their forties or fifties,” says Diaz. RELATED: How to Quit Vaping: A Practical Guide
Quitting Smoking
After just a few days, breathing will become easier and your sense of taste and smell will become more heightened. “Quitting smoking is the best way to stabilize things, and there can be some improvement in the lungs after you’ve stopped smoking as well. We try to get everybody with COPD to get off cigarettes,” says Diaz. There are numerous medicines and resources available to help people quit smoking, including:
Nicotine replacement therapies, such as nicotine gums, patches, and inhalersSmoking cessation medication, such as bupropion (Wellbutrin, Zyban) and varenicline (Chantix)Behavioral therapyTobacco quit lines, such as 800-QUIT-NOW, operated by the National Cancer Institute (NCI)Support groups, cessation classes, and self-help materials. Information is available on websites such as Smokefree.gov.
Indoor air pollution, particularly from the burning of wood and other biomass in fireplaces and stoves. This is not a common cause of COPD in the United States, but it can be a factor in other parts of the world, says Diaz.Industrial dust and chemical fumes in the workplace. People who work in construction or coal mines can be an increased risk for COPD.Secondhand smoke and other pollutantsAsthmaFrequent respiratory infections during childhoodIn rare cases, emphysema can also be caused by an inherited disorder called alpha-1 antitrypsin (AAT) deficiency, in which a normally beneficial enzyme called neutrophil elastase damages alveoli tissue.
Because cigarette smoking contributes to multiple health problems, including lung cancer, the authors emphasize that, in any case, smokers should do their best to stop smoking. The study found that, compared with nonsmokers, certain airway cells in smokers abnormally express a number of genes, all located on chromosome 19, including four genes (NFKBIB, LTBP4, EGLN2, and TGFB1) that have been previously linked to COPD.
Treatment of COPD
The cause of COPD, as well as how severe the condition is, will determine the treatment approach. Treatment for COPD patients focuses on controlling symptoms and improving quality of life. This may include:
Lifestyle changes, such as quitting smoking and making sure you’re maintaining proper nutritionMedications such as bronchodilators, which relax the muscles around the airways and clear mucus from the lungs;spirometry, a breathing test that measures airflow and is used to confirm a diagnosis of COPD, may be used to assess your condition and see whether your medications are working effectively.Pulmonary rehabilitation and oxygen therapySurgery, such as a lung transplant, may also be an option
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Additional reporting by Joseph Bennington-Castro.
