The Instrumental Evaluation of Progression of Dysphagia in Amyotrophic Lateral Sclerosis

Abstract

Background: Swallow dysfunction in amyotrophic lateral sclerosis (ALS) is common. The objective clinical tool most frequently employed in diagnostics for dysphagia is videofluoroscopic examination of swallow safety (VFES). Currently, there is no specific data to support the repeated use of this tool in ALS. This study describes the progressive changes in swallow function in ALS with VFES using a validated dysphagic scale over time, and the value of repeated evaluation with this test. A prospective observational study of 15 patients with a probable or definite diagnosis of ALS (in accordance with El Escorial criteria) was carried out. VFES was carried out at three monthly intervals. Clinical observations were analysed using the Dysphagia Outcome Severity Scale (DOSS) (O’Neill et al. 1999). Data was examined under the stratification of type of disease onset (bulbar and spinal). Analysis of DOSS scores over time showed that patients with ALS experience progressive but non-linear degeneration of swallow function. There was a high incidence of silent aspiration. There was a statistically significant difference in the rate of progression of dysphagia among patients with bulbar onset, compared to those with spinal onset. It was concluded that there is a non-linear progression of dysphagia in ALS. The findings support the benefits of repeated VFES for accurate assessment and treatment of dysphagia, and consequent nutritional decline in ALS.