Dysphagia diagnosis with questionnaire, tongue strength measurement, and FEES in patients with childhood-onset muscular dystrophy

Introduction: Dysphagia in progressive muscle diseases is primarily due to muscle weakness. Objective of our study is to investigate the prevalence and phenotypes of dysphagia in patients with childhood onset muscular dystrophy (MD) with the use of a validated questionnaire, the measurement of tongue strength and Flexible Endoscopic Evaluation of Swallowing (FEES).

Methods: Prospective observational longitudinal study of dysphagia in a cohort of 58 patients attending the Pediatric Department Center for Neuromuscular Diseases. Control participants were 56 age and sex matched healthy volunteers. Dysphagia was evaluated with the Eating Assessment Tool-10 (EAT-10), and the measurement of Maximal Isometric Tongue Pressure (MITP) and tongue endurance (Iowa Oral Performance Instrument-IOPI). Dysphagic patients were submitted to FEES. Recorded data included demographic and anthropometric characteristics, type of MD, feeding status, and spirometry.

Results: Our patients' cohort consisted of 41 children, 11 adolescents, and 6 adults. Based on EAT-10, 20.7% of the patients were dysphagic: 14.63% of children, 27.3% of adolescents and 50% of adults. The main complain was solid food dysphagia. Spirometry parameters mean values for children and adolescent patients corresponded to lower than the fifth percentile. Means of FVC and FEV1 expressed as % predicted for adult patients were 27.8 (SD:25.05) and 28.8 (SD:28.44) respectively. Reduced tongue strength was measured to children aged 9-10, adolescent and adult MD patients. The main FEES findings were pharyngeal residue, spillage of food before the swallow, and supraglottal penetration.

Discussion: This is the first study to use a validated questionnaire to evaluate dysphagia in childhood onset MD and report dyphagia prevalence at different patients' age. This is the first study reporting MITP in children and adults with generalised MD. Tongue pressures are reduced well before clinical signs of dysphagia are present.

Conclusion: Screening of potentially dysphagic MD patients can be based on a validated questionnaire. Patients with an EAT-10 score suggestive of dysphagia at regular follow-up can have the MITP measured and in the case of reduced values a thorough dysphagia evaluation with FEES is indicated.