C75-18 Obstructive Sleep Apnea Among Patients With Alpha-1 Anti-trypsin Deficiency: A Single Center Experience

Rationale

Alpha-1 antitrypsin deficiency (AATD) may increase the risk of obstructive sleep apnea (OSA) compared with the general population. A proposed mechanism is reduced alpha-1 antitrypsin mediated inhibition of elastase, leading to degradation of elastin in upper airway tissues and increased pharyngeal collapsibility during sleep. This study aimed to compare characteristics of patients with AATD and OSA to patients without AATD and OSA.

Methods

This retrospective study was conducted at the University of Rochester Medical Center with IRB approval and informed consent was waived. Patients with AATD and OSA were matched in a 1:2 ratio to PiMM patients with OSA. They were categorized into four groups based on AAT phenotype: (1) homozygous AATD (PiZZ), (2) age-matched PiMM controls for the homozygous group, (3) heterozygous AATD (PiMZ or PiSZ), and (4) age-matched PiMM controls for the heterozygous group. Collected data included demographics, comorbidities, details of AAT testing, and polysomnographic parameters. Univariate and bivariate analyses were performed to compare characteristics across groups. Categorical variables were analyzed using chi-square or Fisher’s exact tests, and continuous variables using t-tests or ANOVA, with two-sided statistical significance defined as p < 0.05. Generative AI was used for language clarity only.

Results

Among 66 homozygous PiZZ patients at our institution, 16 underwent diagnostic testing for OSA and 11 were diagnosed with OSA. Among 180 heterozygous patients, 35 underwent OSA testing and 27 were diagnosed with OSA. Overall, 114 patients including matched controls were analyzed. Differences in sex distribution were observed across groups, with a higher proportion of females among AATD homozygotes compared with heterozygous groups (p < 0.01). BMI differed significantly between groups (p = 0.03), with AATD homozygotes exhibiting a lower BMI than controls (29.1 vs. 37.8 kg/m²). COPD prevalence was higher among AATD homozygotes compared with control homozygotes and heterozygous groups (45.5% vs. 4.6%, p < 0.01). No differences were noted in Epworth Sleepiness Scale or neck circumference. OSA severity did not differ across the four groups with a mean AHI of 28.6 events/hr. When homozygous and heterozygous AATD patients were combined and compared to controls, a greater proportion of AATD patients had mild OSA compared with controls (p = 0.02), although mean AHI again did not differ between groups.

Conclusion

To our knowledge, this is the first study characterizing polysomnographic data in patients with AATD and OSA. In our cohort, homozygous AATD was associated with lower BMI but similar OSA severity compared to controls.

This abstract is funded by: None