A Study in Adults to Learn About Inherited Alpha-1 Antitrypsin Deficiency (AATD) and AATD Related Liver Problems

The liver produces a protein called alpha-1 antitrypsin (AAT). AAT is normally released into the bloodstream. In some people, the liver makes an abnormal version of AAT, called Z-AAT. Z-AAT builds up in liver cells and also leads to low blood levels of AAT (called Alpha-1 Antitrypsin Deficiency or AATD). Over time, this build up leads to different stages of liver problems, if not treated. This is called natural history of AATD. The main aim of this study is to learn about liver problems caused by AATD in adults when not treated over 4 to 8 years. Other aims are to learn what can predict the AATD-liver condition starting and getting better or worse, describe how this condition is currently being diagnosed and watched in normal care, and describe how the AATD also affects an adult's lung function. Data in this study will be collected to include medical history of a participant, including the date AATD was first identified and/or the date on which the first AATD-related liver or lung problems were diagnosed. At study start and then every year until study end, participants will be asked to complete questionnaires (called patient-reported outcomes or PROs).