Clinical and Economic Outcomes in Patients With Alpha-1 Antitrypsin Deficiency in a US Medicare Advantage Population

Background: Alpha-1 antitrypsin deficiency (AATD) testing rates and associated clinical and economic outcomes data in the US Medicare population are limited. Objective: To characterize individuals with AATD, describe clinical outcomes/healthcare research utilization (HCRU) among individuals with chronic obstructive pulmonary disease (COPD) with or without AATD, and identify AATD testing rates among individuals newly diagnosed with COPD. Methods: This retrospective, observational analysis of claims data included individuals from the Humana Research Database (aged 18-89 years) enrolled in Medicare Advantage Prescription Drug plans. Three cohorts included individuals with evidence of AATD; individuals with COPD + AATD matched to individuals with COPD; and individuals with newly diagnosed COPD. AATD health-related outcomes, such as pulmonary and extrapulmonary conditions or events, and economic outcomes, including inpatient admissions, emergency department visits, and physician visits, were examined independently during the pre-index and post-index periods and compared between those with ATTD and without AATD. Results: We identified 1103 individuals with AATD (aged 67.2 ± 10.0 years, 56.3% women, 94.5% White); overall, 22.2% had exacerbations, respiratory distress, and respiratory failure. Individuals with COPD and AATD (n = 742) were matched to individuals with COPD (n = 7420), based on age (68 ± 9 years), sex (55.0% women), and race (97.2% White). The AATD group had a higher proportion of emphysema (47.4% vs 18.7%), COPD exacerbations (40.6% vs 24.7%), and cirrhosis (4.0% vs 1.3%) than the non-AATD group. All-cause inpatient admissions (31.7% vs 27.3%), COPD-specific inpatient admissions (7.4% vs 4.3%), and COPD-specific emergency department visits (19.5% vs 10.8%) were higher in individuals who had ATTD than in those without AATD. AATD testing rates among individuals with newly diagnosed COPD increased slightly over time (2015: 1.07%; 2020: 1.49%). Individuals with COPD and AATD had more comorbidities and higher HCRU. Testing rates increased slightly but remained low. Discussion: Further research is needed to assess the impact of improved AATD testing on those with COPD. Conclusion: Increased awareness, earlier testing, and treatment may reduce the healthcare burden of AATD in the US Medicare population.