Quantitative Measurement of Swallowing Performance Using Iowa Oral Performance Instrument: A Systematic Review and Meta-Analysis

Abstract

Swallowing is a complex but stereotyped motor activity aimed at serving two vital purposes: alimentary function and the protection of upper airways. Therefore, any impairment of the swallowing act can represent a significant clinical and personal problem that needs an accurate diagnosis by means of reliable and non-invasive techniques. Thus, a systematic review and meta-analysis was performed to investigate the reliability of the Iowa Oral Pressure Instrument (IOPI) in distinguishing healthy controls (HC) from patients affected by swallowing disorders or pathologies and conditions that imply dysphagia. A comprehensive search was conducted following the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines and using PubMed, Scopus, Web of Science, Cochrane, and Lilacs databases. Overall, 271 articles were identified and, after a three-step screening, 33 case-control and interventional studies reporting IOPI measurements were included. The methodological quality of the retrieved studies resulted in being at a low risk of bias. The meta-analysis on case-control studies showed that maximum tongue pressure (MIP) values were always higher in HC than in patients, with an overall effect of the MIP difference of 18.2 KPa (17.7–18.7 KPa CI). This result was also confirmed when the sample was split into adults and children, although the MIP difference between HC and patients was greater in children than in adults (21.0 vs. 15.4 KPa in the MIP mean difference overall effect, respectively). Tongue endurance (TE) showed conflicting results among studies, with an overall effect among studies near zero (0.7 s, 0.2–1.1 s CI) and a slight tendency toward higher TE values in HC than in patients. Among the intervention studies, MIP values were higher after treatment than before, with a better outcome after the experimental tongue training exercise than traditional treatments (the MIP mean difference overall effect was 10.8 and 2.3 KPa, respectively). In conclusion, MIP values can be considered as a reliable measure of swallowing function in adults and in children, with a more marked MIP difference between HC and patients for the children population. MIP measures in patients are also able to detect the best outcome on the tongue function after the training exercise compared to traditional training.

Evaluation of the Muscle Strength of the Tongue with the Tongue Digital Spoon (TDS) in Patients with Obstructive Sleep Apnea

“…In addition, the recent meta-analysis by Franciotti et al [25] demonstrates the improvement in patients after experimental tongue training exercises, mainly when a worse value of maximum tongue pressure with the IOPI was found in the initial conditions. It concluded that IOPI proved to be a valid tool to successfully measure tongue pressure and detect the productive effects of tongue training in both healthy and diseased subjects.…”

Early Feasibility of an Activity-Based Intervention for Improving Ingestive Functions in Older Adults with Oropharyngeal Dysphagia

“…In current study, suspected OD was assessed using the GUSS [ 28 ], and further clinical swallow assessments included tongue strength assessments using the IOPI [ 36 ], ingestive skills during a test meal, assessed using the MISA2 [ 39 ], and functional oral intake, assessed using the FOIS [ 29 ]. However, the OD assessment process should optimally involve further instrumental assessment (i.e., fiberoptic endoscopic evaluation of swallowing or videofluoroscopic evaluation of swallowing), which are considered the gold standard for detecting aspiration (including silent aspiration) [ 54 ].…”

“…An indication of sarcopenia of the swallowing musculature was determined from the maximum tongue pressure (MTP), using the Iowa Oral Performance Instrument (IOPI) [ 36 ]. The highest pressure across three trials in kilopascals (kPa) was used.…”

Clinical Assessment of the Correlation Between Tongue Pressure, Modified Mallampati Score, BMI, and Obstructive Sleep Apnea

“…Their study found that both tongue and lip peak pressures were lower in OSA patients compared to healthy controls, with tongue peak pressure correlating with the severity of tongue collapse during drug-induced sleep endoscopy. 40 Moreover, a recent meta-analysis by Franciotti et al 41 demonstrated improvement in patients after engaging in experimental tongue training exercises. However, there was no significant difference in muscle activity of the genioglossus muscle between wakeful healthy individuals and those with OSA.…”