Screening for potential late-onset Pompe disease patients among individuals with suspected sleep apnea: A prospective, multicenter observational Cohort Study in Japan (PSSAP-J Study).

BACKGROUND: Pompe disease is an autosomal recessive disorder caused by a deficiency of acid α-glucosidase (GAA) enzyme. This deficiency induces progressive glycogen accumulation, leading to weakness of the respiratory muscle, including the diaphragm. As established enzyme replacement therapy is available for Pompe disease, earlier detection of potential Late-Onset Pompe Disease (LOPD) and subsequent intervention would have a significant clinical impact. PURPOSE: Our hypothesis was that sleep problems, including sleep-disordered breathing (SDB) and clinical symptoms, may indicate an early stage of LOPD, since decreased respiratory muscle activity often presents initially during sleep. The primary aim of the PSSAP-J study was to demonstrate a higher prevalence of LOPD in a sleep-laboratory-based population. Secondary aims included identifying predictive factors for LOPD from diagnostic polysomnography (PSG) findings and clinical symptoms. METHODS: This prospective multicenter observational cohort study enrolled consecutive patients presenting to sleep laboratories for overnight PSG due to suspected SDB. All patients underwent a Dried Blood Spot (DBS) screening for GAA activity. Genetic analysis of the GAA gene was performed for confirmatory testing when indicated. RESULT: A total of 724 participants were analyzed, although the COVID-19 pandemic prevented reaching the target sample size (n = 1,500). No definitive LOPD cases were confirmed among those who completed the confirmatory testing (prevalence 0%; 95% confidence interval [CI], 0.00%-0.51%). However, seven screen-positive patients declined confirmatory testing and were classified as indeterminate cases. Consequently, we could not definitively establish a higher prevalence or identify predictive factors for LOPD in this population. CONCLUSION: Although the primary study aims could not be confirmed due to the sample size shortfall and the presence of indeterminate cases, our findings highlight the importance for sleep physicians to maintain a high index of suspicion for underlying myopathies, such as LOPD, in clinical practice. CLINICAL TRIAL REGISTRATION: UMIN000039191, UMIN Clinical Trials Registry ( http://www.umin.ac.jp/ctr ).