Chronic obstructive pulmonary disease, or COPD, is a progressive lung disease. The term progressive means the disease may progress through stages of severity. COPD stages include at risk, mild, moderate, and severe. Mild COPD symptoms mimic a bronchial infection and include coughing and sputum production. Despite the mild symptoms, however, damage to the lungs is occurring; treatment is necessary to help slow the progression of the disease.
A spirometer is used to test lung health when patients are tested for COPD. During the test, patients are asked to inhale as deeply as they can and hold air in their lungs while air volume is measured. Then, air is blown out and the spirometer tests how fast the air is moving.
If spirometer tests establish a limited airflow, a patient may be diagnosed with mild COPD. Common symptoms of mild COPD include sputum production in the lungs and chronic cough. During this stage, the symptoms may appear to be a bronchial infection or common cold, and lung function may not “feel” impaired. Despite the lack of recognizable symptoms, physical changes are occurring in the lungs.
Air is moved from the esophagus to the lungs via bronchioles, or tiny airways, into the alveoli. Alveoli are air sacs in the lungs where oxygen is removed from air and passed into the bloodstream. The alveoli are separated into small sacs by thin walls of tissue. In patients with mild COPD, the walls separating the alveoli break down, creating fewer air sacs that are larger in size.
During mild COPD the bronchioles may also be affected without the patient noticing symptoms. Mucus buildup in the lungs may clog the bronchioles making it harder for air to move into the alveoli. As mild COPD progresses, bronchioles may weaken and lose wall strength, causing the airway to collapse on itself.
In some cases, mild COPD may be diagnosed without a spirometer. Patients with emphysema, chronic bronchitis or both may be given a preliminary diagnosis of mild COPD based on previous medical history. Emphysema results from damage to the air sacs in the lungs. Chronic bronchitis is a constant irritation and inflammation of airways leading to the lungs. Together, these two conditions are often referred to as COPD.
It is likely that mild COPD will progress to moderate COPD and eventually to severe COPD. Patients are often advised to stop smoking, if applicable, to slow down the progression of mild COPD. Prescription medications also may be given to open bronchioles and loosen mucus impairing breathing function.