Risk factors and long-term outcomes of oropharyngeal dysphagia in persons with multiple sclerosis: a systematic review protocol.

BACKGROUND: Oropharyngeal dysphagia (OPD) can be functionally debilitating in persons with multiple sclerosis (pwMS). OPD induces alterations in safety and efficiency of food and/or liquid ingestion and may incur negative sequalae such as aspiration pneumonia or malnutrition/dehydration. Early detection and timely management of OPD in pwMS could prevent such complications and reduce mortality rates. Identifying risk factors of OPD relative to its onset or repeat manifestation will enable the development of care pathways that target early assessment and sustained management. The aims of this systematic review are to compile, evaluate, and summarize the existing literature reporting potential risk factors and associated long-term outcomes (e.g., aspiration pneumonia, malnutrition, dehydration, and/or death) of OPD in pwMS. METHODS: We will undertake a systematic review to identify studies that describe patterns and complications of OPD in pwMS. Variables of interest include predictors of OPD along with long-term outcomes. We will search MEDLINE, Embase, CINAHL, AMED, the Cochrane Library, Web of Science, and Scopus. We will consider studies for inclusion if they involve at least 30 adult participants with MS and report risk factors for OPD and/or its long-term outcomes. Studies will be excluded if they refer to esophageal or oropharyngeal dysphagia induced by causes other than multiple sclerosis. Study selection and data extraction will be performed by two independent assessors for abstract and full article review. We will present study characteristics in tables and document research findings for dysphagia-related risk factors or its complications via a narrative format or meta-analysis if warranted (e.g., mean difference and/or risk ratio measurements). All included studies will undergo risk-of-bias assessment conducted independently by two authors with consensus on quality ratings. DISCUSSION: There is a lacune for systematic reviews involving risk factors and long-term outcomes of dysphagia in pwMS to date. Our systematic review will provide the means to develop accurate and efficient management protocols for careful monitoring and evaluation of dysphagia in pwMS. The results of this systematic review will be published in a peer-reviewed journal. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42022340625.

Neuromuscular Electrical Stimulation in Conjunction with Conventional Swallowing Therapy in the Treatment of Dysphagia Caused by Multiple Sclerosis: A Single-Case Experimental Design.

INTRODUCTION: Dysphagia as a consequence of multiple sclerosis (MS) puts individuals at higher risk of dehydration, malnutrition, and aspiration pneumonia. This study intended to investigate the effects of a combined program of neuromuscular electrical stimulation (NMES) and conventional swallowing therapy to improve swallow safety and efficiency, oral intake, and physical, emotional, and functional impacts of dysphagia in people with dysphagia and MS. METHODS: In this single-case experimental study with ABA design, two participants with dysphagia caused by MS underwent 12 sessions therapy during 6 weeks following a baseline of 4 evaluation sessions. They were evaluated 4 more times in the follow-up phase after therapy sessions. Scores of Mann Assessment of Swallowing Ability (MASA), DYsphagia in MUltiple Sclerosis (DYMUS), and timed test of swallowing capacity were obtained at baseline, during treatment, and in the follow-up phases. The Dysphagia Outcome and Severity Scale (DOSS) based on videofluoroscopic swallow studies, Persian-Dysphagia Handicap Index (Persian-DHI), and Functional Oral Intake Scale (FOIS) were also completed before and after treatment. Visual analysis and percentage of nonoverlapping data were calculated. RESULTS: MASA, DYMUS, FOIS, and DHI scores indicated significant improvement in both participants. Although the scores of the timed test of swallowing capacity in participant 1 (B.N.) and DOSS in participant 2 (M.A.) showed no changes, considerable improvements including reducing the amount of residue and the number of swallows required to clear bolus were seen in the posttreatment videofluoroscopic records of both participants. CONCLUSION: NMES in conjunction with conventional dysphagia therapy based on motor learning principles could improve the swallowing function and decrease disabling effects of dysphagia on different aspects of life in participants with dysphagia caused by MS.