Oral muscles are progressively affected in Duchenne muscular dystrophy: implications for dysphagia treatment

Abstract

Dysphagia is reported in advanced stages of Duchenne muscular dystrophy (DMD). The population of DMD is changing due to an increasing survival. We aimed to describe the dysphagia in consecutive stages and to assess the underlying mechanisms of dysphagia in DMD, in order to develop mechanism based recommendations for safe swallowing. In this cross-sectional study, participants were divided into: early and late ambulatory stage (AS, n = 6), early non-ambulatory stage (ENAS, n = 7), and late non-ambulatory stage (LNAS, n = 11). Quantitative oral muscle ultrasound was performed to quantify echo intensity. Swallowing was assessed with a video fluoroscopic swallow study, surface electromyography (sEMG) of the submental muscle group and tongue pressure. Differences in outcome parameters among the three DMD stages were tested with analysis of variance. Oral muscles related to swallowing were progressively affected, starting in the AS with the geniohyoid muscle. Tongue (pseudo) hypertrophy was found in 70 % of patients in the ENAS and LNAS. Oral phase problems and post-swallow residue were observed, mostly in the LNAS with solid food. sEMG and tongue pressure data of swallowing solid food revealed the lowest sEMG amplitude, the longest duration and lowest tongue pressure in the LNAS. In case of swallowing problems in DMD, based on the disturbed mechanisms of swallowing, it is suggested to (1) adjust meals in terms of less solid food, and (2) drink water after meals to clear the oropharyngeal area.

Urologic and gastrointestinal symptoms in the dystroglycanopathies

“…[15][16][17] Dysphagia with solids more than liquids has also been reported in DMD. [18][19][20][21][22] We identified similarly increased occurrence of dysphagia with solids, but did not detect progression of dysphagia with skeletal muscle weakness as reported in studies of DMD. 20,22 While the underlying pathology of dysphagia in dystroglycanopathy is unknown, surface EMG studies of swallowing in a small series of patients with DMD suggest that the muscles involved in swallowing are weak, with dysphagic DMD patients exerting a greater proportion of maximal Figure 3 Gastrointestinal symptoms in dystroglycanopathy (DG) relative to household controls…”

Relationship between tongue thickness and tongue pressure in neuromuscular disorders

“…In addition, the TT of DMD patients, which increases in the advanced stages as previously reported, was proven to be greater than that of DM1 and ALS patients. 6 Although tongue atrophy in ALS patients might be related to tongue weakness, TT in muscular dystrophy, DMD and DM1 patients was not related to tongue strength. In particular, we found that "tongue pseudohypertrophy" in DMD patients had little relationship to tongue weakness (Table 1).…”

“…More recently, they reported again on the convenience and good reproducibility of quantitative muscle ultrasound to measure TT in DMD patients, but they only evaluated patients with muscular dystrophy. 6 In the present study, we not only measured patients with muscular dystrophy, but also those with ALS. In addition, the TT of DMD patients, which increases in the advanced stages as previously reported, was proven to be greater than that of DM1 and ALS patients.…”

206th ENMC International Workshop: Care for a novel group of patients – adults with Duchenne muscular dystrophy Naarden, The Netherlands, 23–25 May 2014

“…35 patients from the cohort are still alive (aged 22-31 years); 18 died (aged [15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30]. Patients were ventilated by NIV (29/53) or IV (33/53).…”