Without a doubt, smoking plays an important role in the development of both chronic bronchitis and emphysema. It is now known that the incidence of COPD increases from 19.7% in men who have never smoked to 87.7% in smokers of more than two packs of cigarettes per day.
This means that smokers with more than two packs of cigarettes per day are 4.5 times more likely to develop COPD than non-smokers. Pipe and cigar smokers have a lower incidence of COPD because they do not inhale smoke as often as cigarette smokers. However, they continue to have a higher incidence of the disease than non-smokers do.
 
Another factor that needs to be taken into account in the development of COPD is air pollution. Although not directly responsible for its development, increased pollution increases the incidence of COPD in smokers. Individuals working in places where there is constant smoke or particles of suspended chemicals also appear to be at an increased risk of developing COPD.
 
We have seen that smoking is a significant causative factor for the development of COPD; however, what will determine if the individual will present chronic bronchitis or emphysema will be their genetic predisposition to it. Thus, a heavy smoker may develop chronic bronchitis or emphysema depending on their genetic characteristics, and there may often be the concomitant onset of the two pathologies.

The overproduction of mucus in the lungs is the main symptom of chronic bronchitis, which consists of a cough with expectoration. This sputum may be whitish or yellowish. There is also a lack of air and inability to perform physical activities, as occurs with asthma, due to the obstruction of the bronchi and the presence of frequent infections.
Those affected also suffer from wheezing (in the chest), which is a manifestation of a difficulty with expiring (also due to bronchial obstruction). Cyanosis, or purplish skin, is also very common in these cases.

Thus, when the physician examines a patient with suspected chronic bronchitis, he or she should use diagnostic means to prove chronic bronchitis (alone or associated with emphysema), as well as to evaluate whether there are complications and assess the severity of the case. The earlier the diagnosis, the less serious the anatomical and functional impairment of the bronchial tree, meaning that treatment is more effective. 

The tests that can be requested by the doctor include chest X-Ray, bronchography and pulmonary function tests.

The chronic bronchitis therapeutic program is extremely similar to that of emphysema and ranges from prophylactic or general measures to more specific solutions aimed at correcting multiple alterations. Treatment is generally long term, and involves physicians, nursing staff, physical therapists and dieticians.

GENERAL MEASURES 

• All factors that aggravate chronic bronchitis should be removed or addressed. Smoking must stop, and all measures for this can be attempted, such as chewing gum or the use of patches, both containing nicotine.

• Avoiding respiratory infections is another measure that should be adopted, due to the fact that infections are one of the most frequent causes of the respiratory condition worsening in these patients. They should be kept at a distance from potential sources of infection (e.g. avoid public gatherings when flu is rife, etc.) and should be treated immediately after the first signs of viral or bacterial infection anywhere in the respiratory tract (thus, this recommendation is also valid for sinusitis, laryngitis, pharyngitis, tonsillitis, etc.).

• Vaccines may be given against the flu virus, as well as against bacteria that most often cause lung infection, in an attempt to prevent the patient from getting respiratory infections.

• It is always advisable to promote adequate humidification of inspired air by means of vaporizers or humidifiers. In addition, patients with chronic bronchitis should always be well hydrated with the amount of water recommended by their doctor. The purpose of these two measures is to ensure bronchial secretions are as liquefied as possible. Within the same line of reasoning, these atients should be instructed to avoid air conditioners, which will dry out ambient air.

• Patients living in extremely polluted areas should be moved away whenever possible when the air pollution index is high.

• The use of tranquilizers should be avoided because these medications can cause a decrease in breathing as a result of their action on the Central Nervous System.

• Respiratory Physiotherapy is of great value in the treatment of COPD and consists of respiratory exercise programs, muscular training, cough exercises, techniques to promote greater outflow of bronchial secretions, exercises to coordinate physical activity with respiration etc., guided by a physiotherapist and the patient's physician. The objective of this measure is to promote improved lung function". 

• Psychological Rehabilitation of COPD patients is important as it ensures they follow the drug treatment properly. This disease is very common in middle-aged men and as it is to some extent limiting, it is commonly associated with depression. Therefore, some patients end up thinking that the treatment is a waste of time, do not take their medicines and
  ontinue smoking. This naturally worsens their clinical condition; patients become more depressed a vicious circle develops.
  Psychotherapy is therefore highly recommended.

• Nutritional supplementation: the treatment of COPD patients should be multidisciplinary, and nutritional intervention should be part of the treatment from the diagnosis of the disease, to prevent and minimize problems relating to nutritional status.

DRUG TREATMENT

Bronchodilators
These are used to reduce bronchial narrowing in chronic bronchitis and thereby improve respiratory capacity. As with asthma, the preferred route of administration of these drugs is also by inhalation.

Mucolytic and Fluidifying Agents
The purpose of this therapy is to reduce the viscosity of the bronchial secretion and thereby prevent the formation of secretion blockages, which will further obstruct the bronchi. This means improveds ciliary activity, transportation of the mucus and, consequently, a reduction of the obstruction.
 
Corticosteroids
Inhaled corticosteroids aim to decrease the inflammatory response occurring in the bronchial tree.

Antibiotics
Antibiotic therapy is reserved for cases in which there is infection.