Chronic respiratory failure negatively affects speech function in patients with bulbar and spinal onset amyotrophic lateral sclerosis: retrospective data from a tertiary referral center

Abstract

Background: Although dysarthria and respiratory failure are widely described in literature as part of the natural history of Amyotrophic lateral sclerosis (ALS), the specific interaction between them has been little explored.

Aim: To investigate the relationship between chronic respiratory failure and the speech of ALS patients.

Materials and methods: In this cross-sectional retrospective study we reviewed the medical records of all patients diagnosed with ALS that were accompanied by a tertiary referral center. In order to determine the presence and degree of speech impairment, the Amyotrophic Lateral Sclerosis Functional Rating Scale-revised (ALSFRS-R) speech sub-scale was used. Respiratory function was assessed through spirometry and through venous blood gasometry obtained from a morning peripheral venous sample. To determine whether differences among groups classified by speech function were significant, maximum and mean spirometry values of participants were compared using multivariate analysis of variance (MANOVA) with Tukey’s post hoc test.

Results: Seventy-five cases were selected, of which 73.3% presented speech impairment and 70.7% respiratory impairment. Respiratory and speech functions were moderately correlated (seated FVC r = 0.64; supine FVC r = 0.60; seated FEV1 r = 0.59 and supine FEV1 r = 0.54, p < .001). Multivariable logistic regression revealed that the following variables were significantly associated with the presence of speech impairment after adjusting for other risk factors: seated FVC (odds ratio [OR] = 0.862) and seated FEV1 (OR = 1.106). The final model was 81.1% predictive of speech impairment. The presence of daytime hypercapnia was not correlated to increasing speech impairment.

Conclusion: The restrictive pattern developed by ALS patients negatively influences speech function. Speech is a complex and multifactorial process, and lung volume presents a pivotal role in its function. Thus, we were able to find that lung volumes presented a significant correlation to speech function, especially in those with bulbar onset and respiratory impairment. Neurobiological and physiological aspects of this relationship should be explored in further studies with the ALS population.

Keywords:

• Amyotrophic lateral sclerosis
• dysarthria
• pulmonary function test
• neuromuscular disorders
• speech disorders

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Notes on contributors

Max Sarmet

Max Sarmet, MSc, is a senior SLP at the Tertiary Referral Center of Neuromuscular diseases of Hospital de Apoio de Brasília (HAB). He obtained the title of MSc in Medical Sciences at University of Brasilia (UnB) and is currently PhD candidate at Graduate Department of Health Science and Technology of UnB. His research focuses on neuromuscular diseases and neuropalliative care, especially concerning swallowing, speech, non-invasive ventilation and pulmonary functions.

Dante Brasil Santos

Dante Brasil Santos, PhD, is a physical therapist at HAB and Associated researcher at Unievangelica. He obtained the title of MSc in Health Sciences at UnB and PhD in Human Movement & Sport Sciences from the Université Paris-Saclay, France. His research focuses on the study of neuromuscular diseases, non-invasive ventilation and lung function, especially in ALS patients.

Laura Davison Mangilli

Laura Davison Mangilli, PhD, is a SLP. She obtained the title of Master of Sciences, PhD and Post Doctoral degree from the College of Medicine of Universidade de São Paulo. She is currently an Associate Professor at the Faculdade de Ceilândia, University of Brasília.

Janae Lyon Million

Janae Lyon Million, MSc, holds an undergraduate degree in Human Biology from the University of California, Santa Cruz, USA. She obtained her Master's from the Botany Department at University of Brasília.

Vinicius Maldaner

Vinicius Maldaner, PhD, is a physical therapist at HAB and Professor at Unievangelica. He obtained his PhD from the Graduate Department of Health Science and Technology of UnB and The University of New Mexico, USA. Currently, he coordinates several studies on respiratory therapy and neuromuscular diseases. His research focuses on the study of neuromuscular diseases, non-invasive ventilation, lung function, intensive care and functional recovery after hospital discharge.

Jorge L. Zeredo

Jorge L. Zeredo, PhD, is a dentist and neuroscientist. He obtained the title of PhD from Tokyo Medical and Dental University, Japan, and did further training in neuroscience at the University of Cambridge, UK. He is currently an Associate Professor at the University of Brasilia, Brazil.