Ask an answerable question (PICO)：
Reports indicate that tongue muscle strength decreases with age, starting as early as the age of 50. Approximately 10% to 20% of older individuals report swallowing difficulty. Difficulties with chewing and swallowing are the main cause of aspiration pneumonia and they result in an increases in-hospital mortality. Previous studies found that oral exercise can not only increase oral muscle strength but also improve ability of swallowing. Therefore, this article uses an evidence-based case study to explore whether oral exercise in middle-aged and older patients with chewing and swallowing difficulties does improve their oral muscle strength or not.
The Method and Analysis of Literature Review：
This study used the PICO (patient–intervention–comparison–outcome) framework to analyze our clinical questions using the following keywords: middle-aged and older people with chewing and swallowing difficulties (P), oral exercise (I), usual care (C), and improved oral muscle strength (O). These keywords combined into MeSH, Emtree, and synonyms, were connected using Boolean logic (i.e., “and” or “or”) to search the literature in Embase, Cochrane and MEDLINE. The inclusion criteria were 1) articles published in the last ten years; 2) the population is over 50 years old with chewing and swallowing difficulties, the intervention is oral exercise, and has subjective and objective assessment tools were used for evaluating oral muscle strength; 3) studies followed quasi-experimental or randomized controlled trial (RCT) designs or were systematic reviews (SRs) and meta-analysis (MA). Initially, 196 studies were acquired, of which 192 did not meet the criteria for inclusion, leaving finally four studies.
Critical Appraisal：
The Joanna Briggs Institute (JBI) 2020 tool was used to evaluate the level of evidence of the included studies. A randomized controlled trial published by Wakabayashi et al. (2018) had a 1C level of evidence. The study findings indicated that tongue muscle strength and swallowing ability were improved following three months of oral exercise training, but not showing statistical significance. The remaining three studies had a 2C level of evidence and demonstrated that oral exercise up to approximately 8 weeks and one month could significantly improve tongue muscle strength and swallowing ability.
Clinical Application of Evidence：
We used seven empirical knowledge translation steps to plan the study’s protocol and adopted a quasi-experimental design (pre- and post-test intervention). Participants were enrolled between March 2021 and September 2021 in an adult medical ward. The oral exercises included a tongue resistance exercise, head flexion exercise against manual resistance, effortful pitch glide and effortful tongue rotation.
Evaluation of Effectiveness：
The Iowa Oral Performance Instrument tool was used to assess oral muscle strength, including tongue pressure, tongue strength during swallowing, and lip pressure, before and after the intervention. Only 37.5% of patients (6/16) completed both the pre-and post-intervention evaluations. At discharge, oral muscle strength was improved after the intervention. The tongue muscle strength of patients was 11.12 ± 9.41 kPa at baseline and 14.37 ± 8.88 kPa at discharge; tongue muscle strength during swallowing improved from 7.08 ± 6.12 kPa to 11.62 ± 7.56 kPa, and lip strength improved from 13.13 ± 8.64 kPa to 17.19 ± 11.79 kPa. However, these differences were not significant (p > 0.05).
Conclusions and Recommendations：
We conclude that oral exercise could improve oral muscle strength in hospitalized middle-aged and elderly patients with chewing and swallowing difficulties. We conducted a rigorous literature review and used an evidence-based approach to develop our intervention. We applied this oral exercise protocol to a clinical setting and found that leaving aside those patients who did not complete post-intervention evaluations, those who did complete the oral exercise regime showed improved oral muscle strength at discharge, but the difference was not statistically significant. This suggests that more educational oral exercise programs should be developed for medical staff, thus making it easier to facilitate the adherence of patients to oral exercise and regimes and improve their chewing and swallowing functions.
陳嬿今* 蘇慧真
