Abstract
In muscular dystrophy patients, the pathologic states of dysphagia that develop differ depending on whether the dysphagia is a complication of Duchenne muscular dystrophy (DMD) or of myotonic dystrophy (MD).
In DMD, which is most common in children, abnormalities in occlusion and in the preparatory and lingual phases of deglutition caused by macroglossia and other factors start to appear when patients enter their teen years. Pharyngeal phase abnormalities start to appear around age 20, with liquids remaining in the pharynx more frequently than solids. Management measures reported to be effective include exercises to improve occlusion, stretching the muscles around the oral cavity to increase the range of motion, and using the balloon dilatation treatment in cases of inadequate opening of the esophageal orifice. Providing assistance with eating and managing patient position to minimize fatigue during eating are also important.
In MD, which is most common in adults, aspiration is considered to affect the prognosis. All phases of the deglutition process can be affected, with abnormalities in the anticipatory phase (such as abnormal eating behavior), in the preparatory phase (such as malocclusion), in the lingual phase (such as inadequate velopharyngeal closure), in the pharyngeal phase (such as material remaining in the pharynx as well as aspirations), and in the esophageal phase (such as esophagectasia). The condition is more serious in patients who have deglutition disorders when swallowing liquids (versus solids). Because aspiration can occur without patient awareness, the risk of suffocation during eating is high. Therefore, close observation is necessary.
Respiratory failure due to the loss of respiratory muscular strength further aggravates the compromised deglutition process. In the early stage of respiratory failure, respiratory management is often limited to nighttime, ie, patients do not use a respirator during the day. However, in DMD patients, it is preferable to use a respirator before or during eating if a patient has decreased percutaneous oxygen saturation. Careful monitoring for aspiration is required for MD patients even after tracheotomy.
