The Relationships among Objective Measures of Tongue Strength and Risk of Aspiration

Abstract

Objective: The objective measures of tongue strength can predict the risk of aspiration. Isometric tongue pressure
and endurance have been reported to be lower in patients who have premature spillage, penetration and/or aspiration
on endoscopic evaluation. We aimed to study the relationships between the objective measures of tongue strength
and risk of aspiration in our population.
Methods: Seventy-five participants were enrolled to the study. The mean age of the participants was 58.3 ±13.6 years
old. They were divided into three groups (25 participants in each group). The first group was normal participants who
have had no history of swallowing problem with normal flexible endoscopic evaluation of swallowing (FEES). The
second group was symptomatic patients who have had history of dysphagia and/or aspiration but normal FEES. The
third group was patients who have had history of dysphagia and/or aspiration with evidence of premature spillage
or laryngeal penetration or aspiration by FEES. All participants underwent objective measurements of the tongue
strength including maximal isometric pressure (MIP) and endurance by Iowa Oral Performance Instrument (IOPI).
The quantitative data between groups were compared using ANOVA and chi-square test was used for qualitative
data. The optimal cut-off points were determined by Receiver Operating Characteristic (ROC) curve.
Results: MIP and endurance were significantly lower in patients who have had premature spillage, penetration
and/or aspiration on endoscopic evaluation. The appropriate cut-off points for high risk group are 35 and 25 kPa
for the anterior and posterior tongue pressure respectively.
Conclusion: The tongue pressure can be used to screen patients who are at risk of aspiration, which will lead to
early investigation and intervention for the management of these patients.