Burden of respiratory syncytial virus in spinal muscular atrophy: a retrospective nationwide cross-sectional and birth cohort study.

Abstract

Background: Spinal muscular atrophy (SMA) is a severe neuromuscular disease associated with a high risk of respiratory complications, yet real-world data on respiratory syncytial virus (RSV) infection in this population remain limited. This study aimed to investigate the severity, hospitalization costs, and seasonal patterns of RSV infections in patients with SMA using real-world data in Taiwan.

Methods: This retrospective study analyzed data from Taiwan's National Health Insurance Research Database from 2009 to 2021. Patients with SMA were identified through at least two outpatient clinic visits and one hospital admission. The analysis included a cross-sectional study and a birth cohort analysis for sensitivity testing. RSV-associated hospitalizations were identified using diagnostic codes for RSV. The main outcomes included ICU admissions, ventilator use, hospitalization costs, timing of RSV onset, and seasonal infection trends.

Results: This study documented 914 hospitalizations in patients with SMA over 13 years, including 14 RSV infections (1.5%). All RSV-related hospitalizations were documented before age 18. In a birth cohort analysis comparing 110 patients with SMA to 2,103,997 individuals from the general population, patients with SMA demonstrated significantly higher RSV hospitalization rates (9.8% vs. 1.6%), ICU admissions (54.5% vs. 4.7%; p < 0.0001), and ventilator use (54.5% vs. 1.7%; p < 0.0001), with a later mean onset (2.54 ± 2.05 years vs. 1.05 ± 1.05 years; p = 0.0073) and substantially higher hospitalization costs (median 967 [560-6,462] USD vs. 683 [487-1002] USD; p = 0.0480). Infections peaked in fall and winter (72.7%) for patients with SMA. ICU admission rates for RSV increased with age and decreased with later SMA onset.

Conclusions: Patients with SMA are at heightened risk for severe RSV infections even beyond infancy, underscoring the need for age-specific and seasonal prevention strategies, particularly for those over two years old.