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

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.

The relationship between pulmonary and swallowing functions in patients with neuromuscular diseases followed up by a tertiary referral center: a cross-sectional study.

INTRODUCTION: Respiratory muscle weakness is common in patients with neuromuscular diseases (NMD). This puts them at risk for dysphagia and other pulmonary complications. OBJECTIVES: To investigate the relationship between pulmonary function and swallowing in NMD. MATERIALS AND METHODS: In this cross-sectional study, medical records of patients undergoing treatment at the Tertiary Referral Center for Neuromuscular Diseases of Hospital de Apoio de Brasília, Brazil, were reviewed. Respiratory function was assessed through spirometry (FVC and FEV1 measured) and swallowing assessed by the Dysphagia Risk Evaluation Protocol and the Functional Oral Intake Scale. RESULTS: Two hundred and twenty-two patients were included. Dysphagia was present in 46.8% of patients and impairment of pulmonary function in 64.0%. The mean FVC observed was 66.9% and FEV1 was 66.0%, indicating restrictive lung disease. A correlation between the decline of pulmonary and swallowing functions was observed in patients with NMDs (FVC vs. DREP, R = 0.46; FVC vs. FOIS, R = 0.42; FEV1 vs. DREP, R = 0.42; FEV1 vs. FOIS, R = 0.40, p<.01). FVC and FEV1 values tend to be lower in patients with dysphagia in the context of NMD. CONCLUSIONS: A positive correlation between pulmonary function and swallowing outcomes was observed in patients with NMD. Despite respiratory and swallowing impairment being widely present in the population with NMD, they require different treatments according to the disease's pathophysiology. Future studies should be conducted to explore the disease-specific relationship between pulmonary function and swallowing in patients with NMD.

A pilot study of the breath stacking technique associated with respiratory muscle endurance training in patients with amyotrophic lateral sclerosis: videofluoroscopic findings in the upper airway.

INTRODUCTION: Bulbar impairment represents a hallmark feature of amyotrophic lateral sclerosis (ALS) that significantly impacts survival and quality of life. Respiratory complications arise because of the weakness of the upper airway and respiratory muscles leading to respiratory failure, impaired swallowing, and reduced airway safety. Breath stacking and respiratory muscle endurance training are techniques that have been described to improve respiratory and bulbar function in patients with ALS. Considering the above, a respiratory technique named TR3 was developed. This study aimed to measure the acute effects of this technique on the upper airway through videofluoroscopy and to assess its clinical trial feasibility in patients with ALS. MATERIAL AND METHODS: In this cross-sectional study, we enrolled participants diagnosed with ALS to perform a single session of TR3. Epidemiological data and baseline assessments were collected. The assessments included kinematics from videofluoroscopy measuring the retropalatal airspace size, the size of the narrowest airway, and the pharyngeal area during rest and TR3. RESULTS: Eight participants were included. During TR3, an acute increase of 15% was observed in the retropalatal airspace size (t = 5.14, p < 0.01), a 123% increase was observed in the size of the narrowest airway (t = -4.18, p < 0.001), and a 277% increase was observed in the pharyngeal area (t = -5.34, p < 0.001). CONCLUSIONS: During the intervention, TR3 showed acute effects in increasing pharyngeal constriction, pharyngeal expansion, retropalatal airspace size, and post-lingual narrowest airway size and is feasible for a larger research program. A clinical trial (NCT04226144) is already being conducted to assess the chronic therapeutic effects of this technique and its impact on the clinical evolution of ALS.