I remember being quite surprised when a survey of multiple sclerosis (MS) patients conducted by MSAA several years ago revealed that 39 percent of respondents indicated they had some degree of swallowing difficulty. Fortunately, most of the swallowing (medically known as dysphagia) problems are mild and are self-managed by the patients.
For individuals who are more severely affected with associated coughing, a choking sensation, or breathing difficulties, tests that include swallowing studies – utilizing x-ray imaging and direct endoscopic visualization of the throat – may yield important information. Such testing can identify specific issues and ensure that problems other than neurological ones are not present.
Swallowing is a complex process starting with jaw and tongue movements, which prepare the solid or liquid (known as the bolus) for transport. Coordination between the tongue and upper throat muscles allows the portion of bolus to be actively moved to the back of the mouth and received by the upper throat.
Coordinated contraction of some throat muscles is needed to protect the upper windpipe (larynx), while the relaxation of another muscle allows for the opening of the upper food transport tube (esophagus). This results in the transfer of the bolus to the esophagus. From this point, involuntary contraction of the esophageal smooth muscle moves the bolus down to the stomach, completing the process.
Disorders of the tongue and the throat muscles or their nerve supply will cause swallowing problems. MS patients may have lesions of the brainstem affecting the direct nerve supply to the tongue and throat muscles. More commonly in my experience, multiple lesions (MS plaques) involving both cerebral hemispheres of the brain cause a lack of coordination of the tongue and throat swallowing muscles. This results in a type of swallowing problem known as pseudobulbar palsy.
For many individuals with MS, altering the consistency of solid food and liquids may be very helpful and improve swallowing function. Retraining to swallow, usually carried out by speech pathologists to ensure advantageous head and neck posture during swallowing, is another useful tool for many people with MS. Other strategies for proper swallowing include: eating smaller, more frequent meals to avoid fatigue while eating; taking smaller bites and chewing these well to reduce the chance of choking; and consciously coordinating breathing with swallowing to reduce the risk of aspiration (inhaling food), which can result in pneumonia.
By Donald A. Barone, DO
Associate Professor and Chief
Division of Neurology, Rowan University School of Osteopathic Medicine
Director, MS Center of South Jersey