The Therapeutic Effect of Swallow Training with a Xanthan Gum-Based Thickener in Addition to Classical Dysphagia Therapy in Chinese Patients with Post-Stroke Oropharyngeal Dysphagia: A Randomized Controlled Study

Objective

In patients with post-stroke oropharyngeal dysphagia (PSOD), classical dysphagia therapy (CDT) continues to provide unsatisfactory outcomes and makes it challenging for them to remove the nasal feeding tube. Increasing bolus viscosity helps prevent aspiration in PSOD. However, conventional starch thickeners enhance post-digestion residue. This study aims to evaluate the efficacy of swallow training with xanthan gum-based thickener (XGT) (Softia G, NUTRI Co., Ltd., Yokkaichi, Japan) additional to CDT in Chinese PSOD patients with a nasogastric tube when compared to CDT alone.

Methods

Patients with PSOD who had a nasogastric tube were randomly assigned to either the experimental group (E-group) or the control group (C-group) in this randomized controlled, single-blind, parallel-group study. Both groups received CDT for 4 weeks. The E-group cases received additional swallow training with a Softia G-prepared hydrogel training material. The Functional Oral Intake Scale (FOIS) and modified volume-viscosity swallow test (M-VVST) for swallowing safety and efficacy according to adjusted Chinese dietary habits were administered before and after treatment. Post-training, both groups' nasogastric tube removal rates were calculated.

Results

One hundred sixty-seven participants (E-group: 82 and C-group: 85) completed the study. The E-group's median score of FOIS improved significantly than the C-group after training (median = 5 vs. 3, P < 0.001). The incidence of coughing, voice changes, oxygen desaturation of 3% or more, pharyngeal residue and piecemeal deglutition in the E-group was significantly lower than that in the C-group (P < 0.05). The E-group had 100% nasogastric tube removal, while the C-group had 28.24% (P < 0.001).

Conclusion

Swallow training with XGT Softia G in addition to CDT can promote swallowing safety and efficacy in Chinese patients with PSOD more effectively than CDT alone.

Predictive Model of Dysphagia and Brain Lesion-Symptom Mapping in Acute Ischemic Stroke

Background and purpose: Early recognition and management of post-stroke dysphagia (PSD) based on MRI may reduce the incidence of complications. Combining clinical symptoms with applications of MRI, we aimed to identify the risk factors of PSD, develop a prediction scale with high accuracy and map key dysphagia brain areas.

Methods: A total of 275 acute ischemic stroke patients were enrolled in this study, and 113 (41.1%) patients were diagnosed with PSD. All patients underwent the water-swallowing test (WST) and volume-viscosity swallow test (V-VST) within first 24 h following admission to assess swallowing. Vascular factors were evaluated and MRI brain scans were obtained within 3 days after symptom onset for each participant admitted to the hospital. T-test, chi-squared test and Fisher’s exact test were used to investigate the associations of various patient characteristics with dysphagia, and multivariable logistic regression models were used to construct a prediction scale. Scale accuracy was assessed using receiver operating characteristic (ROC) analysis. We extracted white matter hyperintensities for each patient as potential brain lesions. Voxel-based lesion-symptom mapping (VLSM) was used to identify key brain areas for dysphagia.

Results: Risk factors related with PSD were older age, history of atrial fibrillation, higher fasting blood glucose, NIH stroke scale, TOAST classification, progressive stroke, middle cerebral artery lesion and anterior cerebral artery lesion. Three variables with most significant associations, including NIH stroke scale, TOAST classification and progressive stroke, combined with age and gender, were used to construct a dysphagia prediction scale with high accuracy (AUC = 0.86). VLSM identified left inferior parietal gyrus as a key brain region for PSD.

Conclusion: Risk factors of PSD were identified and a predictive model of dysphagia was constructed intelligently and automatically. The left inferior parietal gyrus was identified as a key brain area for dysphagia, which provides a new symptom-based treatment target for early rehabilitation in the future.

A Systematic and a Scoping Review on the Psychometrics and Clinical Utility of the Volume-Viscosity Swallow Test (V-VST) in the Clinical Screening and Assessment of Oropharyngeal Dysphagia

(1) Background: The volume-viscosity swallow test (V-VST) is a clinical tool for screening and diagnosis of oropharyngeal dysphagia (OD). Our aims were to examine the clinical utility of the V-VST against videofluoroscopy (VFS) or fiberoptic endoscopic evaluation of swallow (FEES) and to map the V-VST usage with patients at risk of OD across the years since it was described for the first time, carrying a systematic and a scoping review. (2) Methods: We performed both a systematic review (SR) including studies that look at the diagnostic test accuracy, and a scoping review (ScR) with articles published from September 2008 to May 2020. Searches were done in different databases, including PubMed and EMBASE from September 2008 until May 2020, and no language restrictions were applied. A meta-analysis was done in the SR to assess the psychometric properties of the V-VST. Quality of studies was assessed by Dutch Cochrane, QUADAS, GRADE (SR), and STROBE (ScR) criteria. The SR protocol was registered on PROSPERO (registration: CRD42020136252). (3) Results: For the diagnostic accuracy SR: four studies were included. V-VST had a diagnostic sensitivity for OD of 93.17%, 81.39% specificity, and an inter-rater reliability Kappa = 0.77. Likelihood ratios (LHR) for OD were 0.08 (LHR-) and 5.01 (LHR+), and the diagnostic odds ratio for OD was 51.18. Quality of studies in SR was graded as high with low risk of bias. In the ScR: 34 studies were retrieved. They indicated that V-VST has been used internationally to assess OD's prevalence and complications. (4) Conclusions: The V-VST has strong psychometric properties and valid endpoints for OD in different phenotypes of patients. Our results support its utility in the screening and clinical diagnosis and management of OD.

Comparison of two bedside evaluation methods of dysphagia in patients with acute stroke

Background

Dysphagia is a common complication after stroke. Water swallowing test (WST) is a recognised but limited tool in providing details about dysphagia, including severity and how to adjust the diet based on the test results.

Methods

We performed a prospective observational study of comparing WST and volume–viscosity swallow test (V-VST) in patients with acute stroke within 14 days. All patients had WST and if failed would have a V-VST. The primary outcome was to compare the dysphagia levels assessed by these two test tools. The secondary outcome was to explore the predictive capability in patients who were at high risk of pneumonia by these two swallowing tests.

Results

Consecutively 276 patients with stroke were enrolled in our study, and 197 had normal WST. Among 79 patients who had both WST and V-VST, 20 showed swallowing safety and effectiveness by V-VST. The chance of being on tube feeding was strongly related to the positive results of failed WST (p<0.001). Both tests showed good predictive ability in patients with stroke for pneumonia even some of them were placed on tube feeding (p=0.001 in WST and p<0.001 in V-VST).

Conclusions

V-VST performed better as a clinical screening test for dysphagia in patients with acute stroke at the bedside.

Trial registration number

ChiCTR1800016442.