Effects of IOPI on Swallowing Function and Functional Status in Geriatric Patients

In recent years, there have been increasing evidence that tongue strengthening exercises have the ability to improve tongue muscle strength and tongue muscle thickness in the geriatric population. These improvements have a direct impact on the oral phase of swallow, specifically resulting in better orolingual manipulation and propulsion, and increasing intra-oral pressure for better bolus clearance. Reduction in tongue strength and other swallowing parameters can lead to swallowing disorder known as dysphagia. In the healthy ageing population, weakness in swallowing muscles is termed presbyphagia. Geriatric patients have an even higher chance of transitioning from presbyphagia to dysphagia when they become acutely unwell. Studies have also shown that deterioration of the whole-body muscle strength is associated with poorer oral function. Additionally, other studies have also shown that a lower isometric tongue strength might represent diminished functional reserves, which may increase the risk of dysphagia once an insult to the body occurs. There is also evidence that people who have episodes of aspiration have significantly weaker tongue strength at both the anterior and posterior regions. Thus, frail geriatric adults who have weaker skeletal muscles are at a higher risk of developing dysphagia. The tongue is amendable to therapy but current practices in Singapore lack an objective measure. Conventional dysphagia oromotor exercises employ the use of a tongue depressor. This method lacks a quantifiable measure to track outcome and is quite subjective to individual therapists. There is also a lack of practice guideline on recommended resistive load and frequency of exercise in the geriatric population in the acute setting. Other than outcome measures and practice guidelines, there is also a lack of research investigating the correlation of tongue strength and functional status. A few studies have explored the effects of different resistive load used in tongue strengthening exercises, although it was recommended to use a resistive load between 60% to 80% for more positive and extrinsic feedback, and for target population with a lower frustration threshold. Studies also used a longer timeframe of 3-4 weeks of rehabilitation to attain significant effects from skeletal muscle exercise. This, however, is not realistic in the acute geriatric setting in Singapore where the mean length of stay is 10 days. Thus, this study is an exploratory study to investigate the efficacy of using IOPI in this population to improve swallowing function and tongue strength. This study also aims to investigate if a correlation exists between IOPI reading and functional status.