Dysphagia Phenotypes in Spinal Muscular Atrophy: The Past, Present, and Promise for the Future.

The article was not evaluated using a standardized or systematic review method, so it does not provide a comprehensive list of all relevant studies. The etiology and respiratory sections were built from articles chosen by content experts, not from a defined search strategy. Single-case and small series reports were included, and their results cannot be generalized. Dysphagia definitions and swallowing measures were inconsistent, and many reports used unvalidated or subjective clinical outcomes. Therapy studies differed in age at treatment, symptomatic status, and baseline swallowing deficits, making treatment comparisons difficult. Risksiplam trial results were not included because they were not yet published.

Katlyn Elizabeth McGrattan reported grant funding and consulting income from Biogen and AveXis, but no financial interest in those companies, and NIH funding. Christine J. DiDonato reported partial support from NIH, Muscular Dystrophy Association, and CureSMA. Basil T. Darras reported research support from NIH, the Slaney Family Fund for SMA, the SMA Foundation, CureSMA, and Working On Walking, and grants from Ionis Pharmaceuticals, Biogen, Cytokinetics, Sarepta Pharmaceuticals, PTC Therapeutics, Fibrogen, and Summit.

Do not read the 88% good sucking and swallowing result as proof that nusinersen restores swallowing for all treated infants. That result came from a presymptomatic group, while a small symptomatic group showed initial improvement followed by gastrostomy dependence in all patients, and the summarized swallowing measures were not validated.