Definition

Chronic bronchitis, along with pulmonary emphysema and bronchial asthma, is part of a group of illnesses known as chronic obstructive pulmonary diseases (COPD). What they have in common is the chronic obstruction of the bronchi, which limits the free flow of air through the lungs.

Cause

Chronic bronchitis is caused by inflammation of the mucous membrane (a thin layer of tissue that produces a secretion called mucus – also known as phlegm) that lines the inside of the so-called bronchial tree – the part of the body corresponding to the bronchi and their subdivisions. This inflammation leads to increased mucus production and a consequent reduction in airflow from the bronchi to the lungs. This may be perceived as a wheezing sound in the chest. The expectoration becomes abundant, thick, yellowish or greenish, and foul-smelling.

Many people are prone to brief episodes of acute bronchitis during severe colds. However, the condition is only classified as chronic when productive cough – that is, with expectoration – occurs on most days of the month, for three months a year, over at least two consecutive years.

The incidence of chronic bronchitis is higher among men over the age of 40. Closely linked to smoking, the condition can also affect non-smokers who are constantly exposed to dust, smoke, or heavy pollution – although under the same conditions, smokers tend to present a much more severe clinical picture. The disease may also precede or accompany pulmonary emphysema.

Diagnosis

In general, the diagnosis is based on a physical examination and the clinical history reported by the patient. A standard chest X-ray and spirometry (also known as a pulmonary function test, performed using a device called a spirometer, which measures the volume of air the patient inhales and exhales) are auxiliary diagnostic tests. These tests help assess the degree of lung impairment caused by chronic bronchitis.

Symptoms

The disease does not begin suddenly, it is the result of a gradual process.

It initially appears as a “poorly resolved cold”: the person continues to cough and produce large amounts of mucus over several weeks. This issue is often attributed solely to smoking, as most individuals with chronic bronchitis are smokers. Over time, these “colds” begin to cause increasing damage to the lungs. Gradually, the periods of coughing and expectoration become longer until, without realizing it, the person develops a constant productive cough – before, during, and after these “colds.” These symptoms tend to occur more frequently in the morning and during the winter.

Prevention

Avoiding smoking is the number one measure for anyone seeking to stay free from chronic bronchitis. For professionals who work in unsuitable environments with dust and smoke, the only possible prevention is the use of protective equipment, such as masks with special filters. In cases where workers are already affected by the disease, leaving the job may be imperative.

Vaccination against influenza viruses and pneumococcal pneumonia can help prevent lung infections. It is also worthwhile to adopt a healthy routine, including a balanced diet, adequate fluid intake, and regular physical exercise.

Treatment

The first step is to reduce or eliminate factors that may irritate the airways. Quitting smoking is essential: the patient’s clinical and functional condition improves significantly after giving up the habit. It is also advisable to avoid environments with high levels of pollution. Professionals working in areas with airborne particles (such as coal mines) should, whenever possible, be removed from such environments.

The most commonly used medications in treating the disease include bronchodilators, steroids, and mucolytics. Bronchodilators help increase the internal diameter of the bronchi, improving airflow; steroids (or cortisones) are important for reducing the intensity of bronchial inflammation, which plays a key role in chronic bronchitis; and mucolytics can help make thick secretions into thinner ones, which are easier to eliminate.

The most effective way to promote secretion thinning is through inhalation with saline solutions. These also serve as a vehicle for the inhaled administration of bronchodilators.

The mucous membrane that lines and protects the bronchial tree contains glands made up of mucus-secreting cells. In chronic bronchitis, these cells multiply and enlarge, producing thicker mucus that is harder to eliminate through the airways. As a result, the bronchi become a favorable environment for bacterial growth. When a bacterial infection occurs, the mucus becomes purulent, requiring treatment with appropriate antibiotics.

During episodes of bronchial infection, antibiotics are crucial, as they reduce the duration of the crisis and prevent the condition from worsening. The physician typically selects the most appropriate antibiotic based on the most common bacteria that infect chronic bronchitis patients. In rare cases, a bacteriological examination of the sputum is necessary to determine the most suitable antibiotic.

Specific physiotherapy can provide additional benefits by aiding bronchial hygiene and optimizing the patient’s breathing pattern. Routine follow-up should be conducted periodically throughout the course of the disease. However, when signs of a “cold” or respiratory infection appear, it is advisable to seek a doctor as soon as possible.

By Einstein Editorial Board