The Long-term Lung and Respiratory Outcomes of Acid Sphingomyelinase Deficiency: A 10-and 20-year Follow-up Study

Background/Aim: Acid sphingomyelinase deficiency (ASMD) is a rare lysosomal storage disorder characterized by sphingomyelin accumulation causing progressive lung disease, respiratory failure, and death. Patients and Methods: This retrospective observational study used the TriNetX database of electronic health records for 15,108 patients with ASMD from 2000-2020. After exclusions, 8,980 individuals were followed for 10 or 20 years. Outcomes included incidence and prevalence of respiratory disorders. Associations of age, sexand race were assessed. Results: Nearly all respiratory outcomes increased significantly over 20 versus 10 years. Other respiratory disorders, specified respiratory disorders and secondary pulmonary hypertension exhibited the greatest increases, reflecting progressive lung damage in ASMD. While outcomes were poor overall, older age, male sex, and racial minority status associated with greater risks, indicating differences in disease progression or care. Conclusion: This study confirms the progressive nature of ASMD and need for close monitoring and treatment of pulmonary complications to reduce long-term morbidity and mortality. Genetic testing enabling diagnosis even for milder, adult-onset forms is critical to optimize outcomes.