The role genetics play in COPD has never been more evident than in Alpha-1 antitrypsin deficiency. Abbreviated as AAT deficiency or Alpha-1, this commonly misdiagnosed disorder is often overlooked as being one of the possible causes of lung disease. AAT deficiency can also cause liver disease and a skin condition known as panniculitis, but for the purpose of this article, weâ€™ll only be talking about AAT deficiency as it relates to the lungs.1
Alpha-1 is an inherited condition thatâ€™s passed along by one or both parents at birth. When youâ€™re born, you inherit two sets of AAT genes; one from each parent. You will only develop Alpha-1 antitrypsin deficiency if both sets of AAT genes are abnormal. If only one set is abnormal, youâ€™ll be a carrier of Alpha-1, meaning you wonâ€™t actually have the disease, but youâ€™ll be able to pass it on to your unborn children. If both sets of genes are normal, you wonâ€™t have Alpha-1 or be a carrier of the abnormal AAT gene.1
Carriers of AAT deficiency have lower than normal blood levels of AAT, but theyâ€™re rarely as low as someone who has Alpha-1. According to the Alpha-1 Foundation, carriers of AAT deficiency have only a slight risk of developing a disease (COPD, liver disease, etc.) related to Alpha-1. The risk for COPD is higher among some carriers who have family members with COPD.
People with Alpha-1 antitrypsin deficiency donâ€™t produce enough AAT, a protective protein thatâ€™s produced by the liver. AAT safeguards the lungs against inflammation that results from the inhalation of tobacco smoke and/or other environmental airway irritants.
The white blood cells in your lungs are responsible for the production of neutrophil elastase, an enzyme that destroys harmful germs and digests damaged or aging lung cells. In healthy lungs, once neutrophil elastase has done its job, AAT deactivates the enzyme, which keeps it from destroying healthy lung tissue. When the liver produces too little, or no AAT, neutrophil elastase doesnâ€™t shut off, eventually destroying healthy lung tissue. Over time, the destruction of lung tissue can lead to lung disease.1
Smokers and never-smokers alike can be diagnosed with AAT deficiency; however people who smoke run an even greater risk of developing the disease. People who donâ€™t have AAT deficiency (non-Alphas) are usually diagnosed with COPD in their 50’s or 60’s. In contrast, people with Alpha-1 (Alphas) are typically diagnosed with lung disease in their 30’s and 40’s. Moreover, Alphas show more damage in the lower part of their lungs, while non-Alphas show the most damage in the top part of their lungs, especially if they smoke.1
Symptoms of COPD in Alphas are very similar to those in non-Alphas.1Â They include:
Most non-Alphas are diagnosed with lung disease after developing symptoms that prompt a visit to their physician.Â Itâ€™s important to note, however, that a diagnosis of AAT deficiency is not based on symptoms or a medical examination alone; an accurate diagnosis requires a blood test.1 Because smoking cessation and treatment help slow the progression of Alpha-1, being tested as soon as possible is vitally important.
At present, there is no cure for Alpha-1, however, treatment is available to help those diagnosed slow the progression of the disease and live a higher quality of life. Treatment for COPD related to AAT-deficiency is nearly identical to standard COPD treatment with one exception; Augmentation (replacement) therapy is available for Alphas with lung disease to raise the level of AAT in the blood and lungs. Oftentimes, augmentation therapy slows or stops the progression of AAT deficiency, decreasing the risk of further damage to the lungs and increasing survival.1
Screening for Alpha-1 is now included as part of the COPD treatment guidelines established by the Global Initiative for Obstructive Lung Disease (GOLD).2 Â In addition, if you have AAT deficiency or are a carrier of the abnormal gene, your family members should also receive testing for Alpha-1.
According to the World Health Organization, the American Thoracic Society, the European Respiratory Society and the Alpha-1 Foundation, people with the following conditions should be tested1for Alpha-1:
Testing for AAT deficiency involves a simple blood test that can be administered in the privacy of your doctorâ€™s office. You can also receive confidential testing through the Alpha-1 Coded Testing ACT) study.
For more information about testing for Alpha-1, talk to your physician or visit the Alpha-1 Foundation.
Author: Deborah Leader RN, BSN, PHN