Diagnosis of COPD

COPD is a progressive disease for which there is no cure; therefore, early diagnosis of COPD is crucial to ensure that it does not progress to a more debilitating, more severe stage of the disease.⁹,⁶⁸ Smoking is the number one cause of COPD. As such, all smokers should have their Lung Function screened regularly and monitored for signs and symptoms of COPD. However, anyone with a history of exposure to lung irritants, risk factors for the disease, family history or persistent symptoms such as cough, Sputum production, or shortness of breath should also undergo Screening.

Diagnosis of COPD by your physician takes into account your symptoms, past medical history, a physical exam, and clinical testing.⁹ Diagnosis of COPD occurs when both symptoms and your exposure to risk factors are combined with the results of a Spirometry Test, clinical tests, and in some instances, a Biopsy.⁶⁸

COPD includes the overlapof the commonly known diseases of Chronic bronchitis and Emphysema.¹⁰ COPD is characterized by airflow limitation that is not fully reversible. The presence of a Chronic productive cough for at least three months for two successive years in a patient in whom other causes of chronic cough have been excluded indicates chronic bronchitis. Of the two types of COPD chronic bronchitis is seen more often than emphysema. This is most likely due to the diagnostic procedures involved; chronic bronchitis is diagnosed based upon symptoms while emphysema is based upon looking at the lung tissue, which requires an invasive biopsy.

Signs & Symptoms

Monitoring sputum production is important and can give warning with regard to the progression of COPD. Sputum production is usually in a small quantity, thick, and consistent. A change in the mucus may suggest progression of the disease or an infection and should be assessed by a licensed healthcare professional. These are a few of the symptoms that may occur:

• An increase or decrease in the amount of mucus produced
• Thickening of the mucus
• A change in color to yellow or green
• Or the presence of blood

Clinical testing is also a vital aspect of the diagnosis of COPD. Every patient should receive the following tests:

• Spirometry
• Bronchodilator reversibility
• Chest radiograph⁹

Each of these tests gives insight into the progression of the disease for an individual. Selected patients should receive the following tests based upon risk factors and other diseases that may be present:

• Alpha-1 antitrypsin levels
• Static lung volumes
• Blood gases
• Exercise testing
• Respiratory muscle function tests
• Doppler Echocardiography
• Computed tomography CT Scan

If it appears that the patient may also have Sleep apnea, additional testing should be completed to confirm the diagnosis. In general, Oxygen levels in the blood tend to be reduced at night and those with COPD are at an even more reduced level due to the disease. Therefore, it is important for a patient and health care provider to be aware if one has both COPD and sleep Apnea. During the sleep cycle, the muscles that support the chest are naturally relaxed, leading to slower, shallower beathing, which increases the amount of carbon dioxide in the blood. Subsequently, the patient suffers from not having enough oxygen in the blood. This is important for someone who suffers from COPD because they tend to be especially dependent upon the support muscles to maintain proper ventilation.

Testing for COPD

In order to confirm a diagnosis of COPD, a spirometry test should be taken. An important measurement that spirometry provides is the forced expiratory volume in 1 second (FEV1), or the amount of air that can be blown out in 1 second.⁹ This value indicates the lung’s ability to push air out of the lungs and offers information about the severity of restriction or obstruction that may be present within the Airway.⁵³ Another measurement that is taken with a spirometry is the forced vital capacity (FVC) or total amount of air you can blow out of the lungs. These two measurements are then divided (FEV1 /FVC) and compared to people of the same age, height, and gender to determine whether there is an abnormal result or not.

Often a patient will be given a bronchodilator and then repeat the spirometry test to compare the results.⁹ This will indicate whether or not any of the obstruction can be reversed to determine if the patient may have Asthma rather than COPD. If the bronchodilator was to provide relief, then the value of FEV1 will improve. It is important to use a bronchodilator to rule out the possibility of asthma, establish a personal best (highest measured FEV1), and approximate diagnosis. The severity of COPD is determined based upon the value of the post bronchodilator FEV1 /FVC.

The following table adapted from the Global Initiative for Chronic Obstructive Lung Disease (GOLD) standards. Physicians use this table to determine the patient’s severity of COPD.

*Classification based on postbronchodilator FEV1

It is also important to evaluate a patient’s ability to complete simple tasks, such as walking, to assess the amount of oxygen available during such tasks.⁹ One way to do this is through using a sliding scale model. For example, a rating of zero indicates that one is not troubled with breathlessness except during strenuous activity. In contrast, a rating of a four is given to one who is too breathless to leave the house or becomes breathless upon dressing or undressing.

Correct diagnosis of COPD is important so that one can be properly treated and live a full and active life. Appropriate treatment can help to prevent disease progression, relieve symptoms, improve exercise tolerance, to improve health status, prevent and treat complications, prevent and treat Exacerbations, and decrease the risk of death.⁶⁸