A Meta-Analysis and Systematic Review of the Effects of Sensory Modulation Treatments for Neurogenic Oropharyngeal Dysphagia

Abstract

<h3>Background</h3><p>Oropharyngeal sensory stimulation has been applied broadly in clinical dysphagia management, but evidence remains limited.</p><h3>Aims</h3><p>We aimed to determine its effectiveness in treating neurogenic dysphagia (ND).</p><h3>Material and Methods</h3><p>A systematic review and meta-analysis was conducted using studies from PubMed, EMBASE (via Ovid), CINAHL, Web of Science, and the Cochrane Library, searched up to January 2025. We included randomized controlled trials (RCT) comparing sensory stimulations, including electrical and gustatory stimulation, with sham controls or placebo. The outcome measurements included swallowing scales based on clinical and instrumental evaluations.</p><h3>Results</h3><p>We included 16 RCTs (620 participants) in the meta-analysis. Overall, sensory stimulation significantly improved ND (<em>n</em> = 17, SMD [95% CI] = 0.80 [0.41, 1.20], <em>p</em> < 0.001; <em>I</em>² = 71%). Subgroup analysis revealed that the pooled effect size remained significant for electrical stimulation (<em>n</em> = 14, SMD [95% CI] = 0.79 [0.36, 1.23], <em>p</em> < 0.01; <em>I</em>² = 64%), but not for gustatory stimulation (<em>n</em> = 3, SMD [95% CI] = 0.76 [−1.68, 3.20], <em>p</em> = 0.31; <em>I</em>² = 90%). The pooled effect sizes for sensory stimulation were significant for both swallowing measurements (<em>n</em> = 14, SMD [95% CI] = 0.75 [0.27, 1.23], <em>p</em> < 0.01; <em>I</em>² = 76%) and acceleration of decannulation (<em>n</em> = 3, OR [95% CI] = 6.47 [1.10, 38.04], <em>p</em> = 0.05; <em>I</em>² = 3%).</p><h3>Conclusion</h3><p>Oropharyngeal sensory stimulation improves swallowing function and decannulation in ND, with minimal adverse effects. While electrical stimulation shows clear benefits, gustatory effects remain inconclusive. Further studies are warranted to optimize protocols and confirm efficacy.</p>