This bicentric retrospective pilot study evaluated the impact of IPPB (using the Alpha 300® device) on thoracic growth in 7 children with genetically confirmed SMA type I (median age 4.8 years, range 2.6–8.2), comparing the thoracic-to-head circumference ratio (TC/HC) at 4 months before vs. 4 months after IPPB initiation.
TC/HC change reversed from −0.05 ± 0.03 (pre-IPPB) to +0.06 ± 0.07 (post-IPPB), a statistically significant difference (p = 0.04). Six of 7 children showed TC/HC stabilization or improvement after IPPB; all 7 had declining TC/HC before IPPB despite ongoing disease-modifying therapy.
- Very small sample (n = 7) with limited statistical power. - Retrospective design with inability to objectively verify IPPB adherence, frequency, or session duration. - Concurrent disease-modifying therapies (nusinersen, onasemnogene abeparvovec) and NIV are potential confounders that could independently affect thoracic growth.
IPPB appears to reverse the natural TC/HC decline in SMA I children even when disease-modifying therapy is already in place — consider early IPPB initiation before chest deformities become fixed. Regular TC/HC monitoring is a simple bedside tool to track respiratory progression in this population.
Explore related topics
