Up to 70% of tobacco-induced COPD

A World Health Organization briefing highlights the impact of tobacco on the onset and development of chronic obstructive pulmonary disease (COPD). Tobacco products and smoke are major causes of COPD and related conditions. Quitting smoking and smoke exposure are the first steps toward reversing COPD.

Chronic obstructive pulmonary disease (COPD) killed 3.23 million people worldwide in 2019 and is strongly correlated with smoking. It is the third leading cause of death overall, with a five-year mortality rate of 25%. An estimated 392 million people are affected by COPD worldwide, two-thirds of them in low- and middle-income countries. Like cancers and cardiovascular diseases, COPD is one of the noncommunicable diseases (NCDs), whose development has increased in recent decades and to which the World Health Organization (WHO) is drawing attention. It is with this in mind that the WHO has just dedicated a summary to the links between tobacco and COPD.[1].

Smoking, a major risk of COPD

Whether active or passive, smoking is a major risk factor for developing COPD. Tobacco smoke contains thousands of chemical compounds, dozens of which are toxic and carcinogenic. This toxicity can be compounded by the presence of additives added to tobacco products to facilitate their consumption.

Inhaling tobacco smoke leads to chronic inflammation of the airways, as well as infections, oxidative stress, and damage to gas exchange within the lungs. Prolonged exposure to this smoke, including secondhand smoke, can lead to the progressive and irreversible development of COPD. This leads to a narrowing of the airways, and therefore a reduction in airflow, which impairs lung function. It manifests as a chronic cough, shortness of breath, and phlegm production, and negatively impacts overall health. It is estimated that 70% of COPD cases in high-income countries are caused by tobacco smoke, while exposure to environmental pollution is responsible for 60% of cases in low- and middle-income countries.

Many associated pathologies

Having COPD also predisposes people to other health problems. People with COPD are four to six times more likely to develop lung cancer than the general population. These two conditions share common symptoms, such as chronic cough, shortness of breath, and chest pain. People with COPD are also more prone to cardiovascular risks, as chronic respiratory inflammation can reduce blood flow and increase the risk of blood clots. People with asthma, respiratory infections, or allergies who are exposed to secondhand smoke are also more likely to develop or worsen COPD. Intrauterine exposure to tobacco smoke increases the risk of later developing COPD or lung cancer.

In all these situations, quitting smoking is an essential prerequisite. This helps reduce the progression of COPD and the risk of developing lung cancer. It also limits the risk of developing complications related to COPD, particularly cardiovascular disease or type 2 diabetes. In terms of public health, reducing COPD in the general population involves, in addition to preventing people from starting to smoke, encouraging smoking cessation and facilitating smokers' access to healthcare professionals.

Impact of new tobacco and nicotine products on COPD

While tobacco smoke is a well-identified vector of COPD, other tobacco and nicotine products can also have an impact on the development of this disease:

• Oral tobacco products (chewing, snuff or snus)[2]) do not produce smoke, but contain many chemicals and toxins that can cause mouth and throat cancer, which can indirectly affect the lungs.
• Heated tobacco products (IQOS, in France) also emit numerous toxic particles that can trigger persistent allergies or cause inflammatory lesions of the airways – the main cause of COPD. Although their manufacturers claim them to be less harmful than conventional cigarettes, heated tobacco products affect the lungs in the same way as conventional cigarettes. The high prevalence of COPD among dual users of heated and smoked tobacco indicates that there is no risk reduction in this regard.
• E-cigarette aerosols can worsen respiratory symptoms and reduce lung function. The direct impact of vaping on COPD is unclear, but it may be a risk factor for COPD in people who have never smoked. The long-term effects of vaping on the respiratory system remain to be evaluated.

Because children and adolescents' lungs are more vulnerable to COPD risk factors, the WHO recommends implementing protective measures against marketing strategies targeting them, whether for conventional cigarettes or other tobacco or nicotine products.

Keywords: COPD, chronic inflammation, passive smoking, heated tobacco, electronic cigarette

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[1] Tobacco and chronic obstructive pulmonary disease (‎COPD), WHO tobacco knowledge summaries, 8 p., published November 14, 2023, accessed November 17, 2023

[2] Snus are tobacco pouches that are placed between the lip and gum. They are often confused with nicotine pouches, which are used in the same way but do not contain tobacco.