Factors influencing initiation of pharyngeal swallow in healthy adults

Purpose: The purpose of this study was to investigate factors influencing the initiation of pharyngeal swallow (IPS) in healthy, nondysphagic adults. Method: A total of 195 healthy participants ranging in age from 21 to 89 years participated in a modified barium swallow study. IPS was quantified using the Modified Barium Swallow Impairment Profile standardized scoring system across nine swallowing tasks observed in the lateral viewing plane for each participant. Results: Large variability for bolus head location at time of hyoid burst (IPS) was observed within this healthy cohort, ranging from the ramus of the mandible to the pyriform sinuses. Significant effects of bolus volume, viscosity, sex, and race were also observed. Conclusion: Study findings indicate that IPS is variable in healthy adults and influenced by volume, viscosity, sex, and race. Thus, variability in IPS may be considered typical in otherwise nondysphagic adults. The clinical significance of high Modified Barium Swallow Impairment Profile IPS scores in dysphagic patients, therefore, must be considered within the context of other swallowing impairments. Supplemental Material: https://doi.org/10.23641/asha. 12735935.