Alpha-1 Antitrypsin Deficiency in Patients With Cirrhosis in a US National Cohort

INTRODUCTION: Alpha-1 antitrypsin deficiency (AATD) is a genetic condition that increases susceptibility to chronic lung and liver diseases. There are limited data on testing rates in patients with cirrhosis. Guidelines recommend AATD testing in cryptogenic liver disease but not in patients with an established etiology. We aimed to quantify AATD testing patterns in a national cohort of patients with cirrhosis to inform guidelines. METHODS: In this retrospective cohort study of veterans with a new diagnosis of cirrhosis between January 1, 2008 and January 31, 2020, with follow-up until February 23, 2023, we identified predictors of testing, and of severe AATD (alpha-1 antitrypsin [AAT] < 57 mg/dL or PiSZ/PiZZ phenotype/genotype). RESULTS: Of the 126,210 patients with cirrhosis, 42,403 (33.6%) were tested, including 38,189 (30.3%) for AAT levels only, 1,103 (0.8%) for genotype/phenotype only, and 3,011 (2.4%) for both. Factors associated with higher AATD testing included specialist evaluation and White race, whereas patients with chronic obstructive pulmonary disease, hepatitis B/C, hepatocellular carcinoma, and hepatic decompensation were less likely to be tested. Only half of the patients with AAT levels of