Clinical Measures of Bulbar Dysfunction in ALS.

Yana Yunusova,Carolina Barnett,Jordan R Green,Emily K Plowman,Peter Bede

doi:10.3389/fneur.2019.00106

Abstract

Bulbar impairment represents a hallmark feature of Amyotrophic Lateral Sclerosis (ALS) that significantly impacts survival and quality of life. Speech and swallowing dysfunction are key contributors to the clinical heterogeneity of ALS and require well-timed and carefully coordinated interventions. The accurate clinical, radiological and electrophysiological assessment of bulbar dysfunction in ALS is one of the most multidisciplinary aspects of ALS care, requiring expert input from speech-language pathologists (SLPs), neurologists, otolaryngologists, augmentative alternative communication (AAC) specialists, dieticians, and electrophysiologists—each with their own evaluation strategies and assessment tools. The need to systematically evaluate the comparative advantages and drawbacks of various bulbar assessment instruments and to develop integrated assessment protocols is increasingly recognized. In this review, we provide a comprehensive appraisal of the most commonly utilized clinical tools for assessing and monitoring bulbar dysfunction in ALS based on the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) evaluation framework. Despite a plethora of assessment tools, considerable geographical differences exist in bulbar assessment practices and individual instruments exhibit considerable limitations. The gaps identified in the literature offer unique opportunities for the optimization of existing and development of new tools both for clinical and research applications. The multicenter validation and standardization of these instruments will be essential for guideline development and best practice recommendations.

Highlights

Amyotrophic Lateral Sclerosis (ALS) is a relentlessly progressive neurodegenerative disease with considerable clinical heterogeneity compared to other neurodegenerative conditions
The objective of this paper is to provide a review of established bulbar measures in ALS from a diagnostic, screening and disease monitoring perspective
Well-established method in dysarthria assessment in speech-language pathologists (SLPs); reliability is established [26] Well established in ALS; showed sensitivity to prodromal stage of dysphagia and sensitivity to change [27,28,29] Validated and reliability assessed in a large non-ALS cohort; differentiated safe vs. unsafe swallowers in ALS; cut-off of 8 or higher indicates high likelihood of dysphagia (3.1 times); sensitivity 86%, specificity 76%; [30] quick and easy, low administrative burden for scoring Validated in general patient populations with very high sensitivity but poor specificity; quick and easy to use Objective, instrumental; validity, reliability, sensitivity and specificity, depending on the measure, relative to VFS, have been established in ALS [32]

Summary

Introduction

ALS is a relentlessly progressive neurodegenerative disease with considerable clinical heterogeneity compared to other neurodegenerative conditions. Bulbar impairment (oro-motor, dysarthria and dysphagia) is a hallmark feature of the disease and has been associated with the condition since its earliest descriptions [1]. Dysphagia in ALS may lead to weight loss, malnutrition, dehydration, aspiration pneumonia, hospitalization and reduced quality of life [12, 13]. Despite these important sequelae, bulbar impairment in ALS is relatively understudied, and the research literature is sparse [14]. Validated diagnostic, monitoring and prognostic markers of bulbar dysfunction are lacking and clinical assessment practices vary considerably across various centers [16]

Objectives

Findings

Discussion

Conclusion