Usually, swallowing disorders are caused by neurological or esophageal problems or by medications. They can lead to health problems, such as malnutrition and respiratory complications, and social problems.

Their frequency is high in the elderly, especially in institutions, but they are probably underestimated and underdiagnosed. It is useful to screen patients with a swallowing test, especially since the symptoms are not always easy to detect.

It allows us to carry out additional examinations and offer individualized care, in particular on how to eat and stay hydrated.

Swallowing in three stages

1. Food or liquids are sucked, chewed, and moved down the throat.
2. Pharyngeal phase: food passes into the throat. The upper esophageal sphincter, which is the tube that goes from the mouth to the stomach, opens, allowing the bolus to pass into the esophagus. The airways are closed to prevent food or any liquid from entering. Food entering the airways can cause coughing or choking.
3. The esophageal phase begins after the esophagus is closed and ends with the arrival of the bolus in the stomach. Food may get stuck in the esophagus or you may vomit if there is a problem with the esophagus.

Esophageal peristalsis includes a first phase triggered during swallowing by receptors in the posterior pharyngeal wall. The second peristaltic phase is triggered by the arrival of the bolus and the dilation of the esophagus.

Signs of trouble swallowing

The swallowing disorder is called dysphagia.

General signs of a swallowing problem can include:

• A cough during or just after eating or drinking
• Extra effort or time needed to chew or swallow
• Food or liquid leaking from the mouth
• Food stuck in mouth
• Having trouble breathing after meals
• Weight loss

As a result, the person with swallowing difficulties may have:

• Dehydration or malnutrition.
• Food or liquid entering the airways.
• Pneumonia or other lung infection.

Oropharyngeal dysphagia

Oropharyngeal dysphagia is a swallowing disorder that is caused by a structural or functional problem.

Consequences include airway blockage, food transfer into the airways, and aspiration pneumonia.

These eating issues are often accompanied by significant weight loss and have a psychological impact.

Causes of swallowing disorders

Many diseases can cause swallowing problems.

Medications. It is difficult to chew and swallow some medications that cause a dry mouth. Others cause a sedative effect or a decrease in the activity of the central nervous system. Here is a list:

• Anxiolytics and some sleeping pills.
• Certain antibiotics (aminoglycosides, erythromycin), botulinum toxin or penicillamine can block the neuromuscular junction.
• Corticosteroids, colchicine, or statins can decrease muscle tone.
• Drugs that lower dopamine levels (antipsychotics, antiemetics or antiparkinsonian drugs that cause undesirable motor effects (e.g. dyskinesias), among others in the mouth and face.
• All drugs that lower acetylcholine levels such as tricyclic antidepressants and selective serotonin reuptake inhibitors.
• Opiates or inhaled bronchodilators can also cause xerostomia.
• NSAIDs can irritate the lining of the esophagus, which is a cause of trouble swallowing.

Other causes are related to brain or nerve damage by:

• Cerebrovascular accident (CVA). Strokes are an important cause of dysphagia, particularly when they affect the brain stem or cortical areas involved in swallowing. During the acute phase of stroke, dysphagia is associated with increased mortality and an increased risk of institutionalization.
• Parkinson disease. The prevalence of dysphagia in Parkinson’s disease varies between 30% and more than 80% depending on the study. Swallowing disorders can occur very early during the disease, or even precede the appearance of other classic motor signs.
• Dementias. All forms of dementia can be accompanied by swallowing disorders, particularly in the severe stage of the disease, while attention disorders and praxis disorders are more significant. Neuroimaging studies indicate a decrease in activity of cortical areas during swallowing in Alzheimer’s patients.
• Amyotrophic lateral sclerosis (or Lou Gehrig’s disease). Swallowing disorders are caused by weakness of the various muscles involved in swallowing, resulting in an increased risk of malnutrition.
• Other neurological disorders or diseases: multiple sclerosis, muscular dystrophy and cerebral palsy, spinal cord injury.
• Disorders or diseases related to the head or neck, such as certain cancers (mouth, throat, or esophagus).
• Head or neck injuries.
• Mouth or neck surgery.
• Poor dentition, missing teeth or ill-fitting dentures.

Evaluation of swallowing disorders

A history and clinical examination are a first step before proceeding to a clinical evaluation or additional examinations.

The anamnesis

The doctor inquires about the patient’s history and current illnesses (e.g. neurological), about his complaints (e.g. pain when swallowing), current drug treatments, the social context (entourage, presence or absence of a caregiver ) and the type of power supply usually used.

Apart from the emergency situation of an obvious aspiration bronchoaspiration, the signs suggestive of dysphagia are often non-specific.

The clinical examination

The examination includes a complete neurological and ENT examination, in particular of the oropharyngeal and cervical region. Cough reflex, voice, speech, saliva production and swallowing, oral status, and breathing at rest are also assessed.

Depending on the cognitive state of the patient, other complementary examinations will be carried out.

Swallowing test

Different evaluation methods are available to detect and quantify swallowing disorders.

Some tests – including the water test – require the patient to swallow a predetermined volume of liquid, usually water.

Videofluoroscopy. This examination allows a real-time dynamic analysis of the different phases of swallowing, the patient swallowing a barium-based contrast product.

Flexible nasal endoscopy.  It allows direct visualization of the nasopharynx, pharynx and larynx.

Pharyngoesophageal manometry. It measures pharyngeal pressure during swallowing.

There is also a swallowing screening tool: the Eating Assessment Tool (EAT-10)

Treatments

Management depends on the causes identified during the assessment.

A first step is to train the family and caregivers to detect signs of swallowing disorders and to supervise patients at risk at mealtimes.

It is important to ensure regular oral hygiene.

Management then includes several components: postural adjustment, learning compensatory maneuvers and changes in the volume and consistency of the bolus.

Proper positioning of the patient (ideally vertical and symmetrical) at mealtime reduces the risk of choking. The environment in which the meal is taken should be in a calm atmosphere without distraction.

Rehabilitation based on muscle strengthening of the tongue, respiratory muscles, movements of the lips, cheeks, larynx and vocal cords can improve dysphagia following a stroke.