Common Symptoms The most common symptoms of COPD are -  a cough that does not go away   - coughing up lots of sputum (mucus).  a cough that does not go away coughing up lots of sputum (mucus). These symptoms often start years before the flow of air in and out of the lungs is reduced. Not everyone who has a cough and sputum goes on to develop COPD. Other common symptoms of COPD include -  shortness of breath while doing activities you used to be able to do  -  wheezing (a whistling sound when you breathe)  - tightness in the chest.  shortness of breath while doing activities you used to be able to do wheezing (a whistling sound when you breathe) tightness in the chest. Getting a Diagnosis Your doctor will diagnose COPD based on your signs and symptoms, your medical and family histories, and test results. If your doctor thinks you may have COPD, he or she will examine you, listen to your lungs, and ask you questions about your medical history, and what lung irritants you may have been around for long periods of time. The Spirometry Test To confirm a diagnosis of COPD, your doctor will use a breathing test called spirometry. The test is easy and painless and shows how much air you can breathe out and measures how fast you can breathe it out. In a spirometry test, you breathe hard into a large hose connected to a machine called a spirometer. When you breathe out, the spirometer measures how much air your lungs can hold and how fast you can blow air out of your lungs. Spirometry can detect COPD before symptoms develop. Your doctor also might use the test results to find out how severe your COPD is and to help set your treatment goals. The test results also may help find out whether another condition, such as asthma or heart failure, is causing your symptoms. Determining COPD Severity Based on this test, your doctor can determine if you have COPD and how severe it is. There are four levels of severity for COPD: - people at risk for COPD  - people with mild COPD  - people with moderate COPD  - people with severe COPD. people at risk for COPD people with mild COPD people with moderate COPD people with severe COPD. People at risk for developing COPD have a normal breathing test and mild symptoms such as chronic cough and sputum (mucus) production. People with mild COPD have mild breathing limitation. Symptoms may include a chronic cough and sputum (mucus) production. At this stage, you may not be aware that airflow in your lungs is reduced. People with moderate COPD have a breathing test that shows worsening airflow blockages. Symptoms may be worse than with mild COPD and you may experience shortness of breath while working hard, walking fast, or doing brisk activity. At this stage, you would seek medical attention. People with severe COPD have a breathing test that shows severe limitation of the airflow. People with severe COPD will be short of breath after just a little activity. In very severe COPD, complications like respiratory failure or signs of heart failure may develop. At this stage, quality of life is impaired and worsening symptoms may be life-threatening. Other Tests Other tests are used to rule out other causes of the symptoms. - Bronchodilator reversibility testing uses the spirometer and medications called bronchodilators to assess whether breathing problems may be caused by asthma. Bronchodilator reversibility testing uses the spirometer and medications called bronchodilators to assess whether breathing problems may be caused by asthma. -  A chest X-ray or a chest CT scan may also be ordered by your doctor. These tests create pictures of the structures inside your chest, such as your heart, lungs, and blood vessels. The pictures can show signs of COPD. They also may show whether another condition, such as heart failure, is causing your symptoms.  A chest X-ray or a chest CT scan may also be ordered by your doctor. These tests create pictures of the structures inside your chest, such as your heart, lungs, and blood vessels. The pictures can show signs of COPD. They also may show whether another condition, such as heart failure, is causing your symptoms. - An arterial blood gas test is another test that is used. This blood test shows the oxygen level in the blood to see how severe your COPD is and whether you need oxygen therapy. An arterial blood gas test is another test that is used. This blood test shows the oxygen level in the blood to see how severe your COPD is and whether you need oxygen therapy.