RecruitingClinical trialA Study in Adults to Learn About Inherited Alpha-1 Antitrypsin Deficiency (AATD) and AATD Related Liver ProblemsThe main aim of this study is to learn about liver problems caused by the lack of alpha-1 antitrypsin (called Alpha-1 Antitrypsin Deficiency or AATD) in adults when not treated (this is called the natural history of a condition) over 5 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 hospital care, and describe how the AATD also affects and 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 completed questionnaires (called patient-reported outcomes or PRO).