What Is Dysphagia? What Causes Dysphagia?

Dysphagia means swallowing difficulties, and usually caused by nerve or muscle problems. Dysphagia may occur after a stroke, throat and mouth cancer, gastro-oesophageal reflux disease (GORD), or as a symptoms of several different neurological conditions disorders. Pain can be the sole cause of dysphagia; a pain in the throat makes swallowing difficult. However, dysphagia can be distinguished from similar symptoms including odynophagia, which is defined as painful swallowing, and globus, when the patient feels a lump in the throat. Although the medical term - dysphagia - is known as a symptoms or sign in most medical criteria, it can and is sometimes used as a condition in its own right.

The term "dysphagia" comes from the Greek root word dys which means "difficulty or disordered", and phagia meaning "to eat".

According to Medilexicon's medical dictionary:

Dysphagia is Difficulty in swallowing.

A typical "swallow" involves several different muscles and nerves.

• Seeing, smelling and tasting - when we see, smell or taste food/drink we produce saliva, which is designed to make chewing easier.
• We chew the food until it becomes a soft bolus - a mass of food that is ready to swallow. The tongue pushes the bolus to the back of the mouth to the pharynx. From this moment onwards, the swallowing movement is a reflex action (automatic).
• The larynx (voice box) closes to prevent food/liquid from going down the windpipe into the lungs. The gulping action pushes the food into the esophagus, which has muscular walls and pushes the food down to the stomach.

Dysphagia can be caused by a difficulty anywhere in the swallowing process described above.

There are two types of dysphagia:

• Oropharyngeal dysphagia (high dysphagia). The problem is in the mouth and/or throat. This is usually caused by a neurological problem - there is something wrong with the nerves (and muscles). Doctors say this type of dysphagia is more difficult to treat.
  
• Esophageal dysphagia (low dysphagia). The problem is in the esophagus. This is usually because of some blockage or irritation. Often, a surgical procedure is required to solve the problem

What are the signs and symptoms of dysphagia?

A symptom is something the patient feels and reports, while a sign is something other people, such as the doctor detect. For example, pain may be a symptom while a rash may be a sign. Some patients may have dysphagia and be unaware of it - in such cases it may go undiagnosed and not be treated, raising the risk of aspiration and aspiration pneumonia. Aspiration means literally inhaling the food to your lungs, or swallowing the food down the wrong way. Doctors say that undiagnosed dysphagia may also lead to health problems due to dehydration and malnutrition.

If there is pain in swallowing in the mouth or esophagus (odynophagia) the doctor will most likely try to rule out carcinoma (cancer).

Signs and symptoms that may be linked to dysphagia:

• Choking when eating
• Coughing or gagging when swallowing
• Drooling
• Food or stomach acid backing up into the throat
• Recurrent heartburn
• Hoarseness
• Pain while swallowing
• Sensation of food getting stuck in the throat or chest, or behind the breastbone
• Unexplained weight loss
• Bringing food back up (regurgitation)
• Difficulty controlling food in the mouth
• Difficulty initiating swallowing (gulping action)
• Recurrent pneumonia
• Inability to control saliva in the mouth

Patients typically say the food has got stuck.

What causes dysphagia?

There are numerous possible causes of dysphagia, including:

• Aging - the muscles used in swallowing naturally become weaker and may cause swallowing problems in very old age. Patients should get help, because there is treatment for age-related dysphagia.
• Amyotrophic Lateral Sclerosis (motor neuron disease) - an incurable form of progressive neurodegeneration - over time the nerves in the spine and brain progressively lose function. In the case of motor neuron disease, motor neurons - types of nerve cells - are affected.
• Bell's Palsy - either weakness or paralysis of the muscles on one side of the face due to malfunction of the facial nerve.
• Cerebrovascular Stroke - when some brain cells die due to lack of oxygen because blood flow is impaired.
• GERD (gastroesophageal reflux disease) - occurs when gastric acid from the stomach goes up into the esophagus, often causing inflammation of the esophagus - esophagitis.
• Eosinophilic esophagitis - severely elevated levels of eosinophils -- a type of white blood cell - in the esophagus. These eosinophils grow in an uncontrolled manner and attack the gastrointestinal system, leading to vomiting and difficulty with growth and swallowing food.
• Multiple Sclerosis - the central nervous system (CNS) is attacked by the person's own immune system, destroying myelin, which protects the nerves.
• Myasthenia Gravis (Goldflam disease) - the muscles under our voluntary control become easily tired and weak because there is a problem with how the nerves stimulate the contraction of muscles. Also an autoimmune disorder.
• Parkinson's disease & Parkinsonism syndromes - Parkinson's disease is a gradually progressive, degenerative neurologic disorder which typically impairs the patient's motor skills, speech, writing, as well as some other functions.
• Radiation - some patients who received radiation therapy (radiotherapy) to the neck and head area may have swallowing difficulties.
• Cleft lip and palate - types of abnormal developments of the face during pregnancy - they are types of clefting congenital deformities, due to incomplete fusing of bones in the head, resulting in gaps (clefts) in the palate and lip to nose area.
• Scleroderma - a group of rare chronic autoimmune diseases in which the skin and connective tissues tighten and harden; it is a progressive disease.
• Snake venom and other neurotoxins
• Some cancers
• Xerostomia (dry mouth) - there is not enough saliva to keep the mouth wet.

What are the complications of dysphagia?

Pneumonia and upper respiratory infections - specifically aspiration pneumonia which can occur when you swallow something down the wrong way and it enters the lungs.

Malnutrition - this is especially the case with people who are not aware of their dysphagia and are not being treated for it. They may simply not be getting enough vital nutrients for good health.

Dehydration - if you cannot drink properly, your fluid intake may be undermined, leading to dehydration (shortage of liquid in the body).

How is dysphagia diagnosed?

The doctor will try to determine where the problem lies - which part of the swallowing process is causing the difficulty. The patient will be asked about symptoms, how long they have been present, whether the problem is with liquids, solids or both. The patient will be weighed, and asked whether the present weight is about right.

Water-swallow test - the patient will be asked to swallow a quantity of water as fast as possible. Some soft food may be given as well.

Barium Swallow Test - the patient swallows a barium containing liquid. Barium shows up in x-rays and helps the doctor identify what is going on in the esophagus in more detail, especially muscular activity. A barium meal may also be used (with food).

Manometry - this study measures the pressure changes produced by contractions of the muscular portions of the esophagus. This test may be used when an endoscopy yields normal results.

Chest x-ray - to rule out bronchial carcinoma.

What is the treatment for dysphagia?

Treatment for oropharyngeal dysphagia (high dysphagia) - as the problem is mostly caused by a neurological problem, providing effective treatment is challenging. Patients with Parkinson's disease usually respond well to Parkinson's disease medication and the dysphagia is generally under control.

• Swallowing therapy - this will be done with a Speech and Language Therapist. The patient will learn new ways of swallowing properly. Some exercises will be taught and practiced to improve the muscles and how they respond.
• Diet - this is usually done with a Nutritionist. Some foods and liquids, or combinations of them are easier to swallow. While eating the easiest-to-swallow foods, it is also important that the patient has a well-balanced diet.
• Feeding through a tube - if the patient is at risk of malnutrition or dehydration they may need to be feed through a nasal tube (nasogastric tube) or PEG (percutaneous endoscopic gastrostomy). Nasogastric tubes need to be replaced every two to four weeks. PEG tubes need to be replaced every two to three years. According to the National Health Service (NHS), UK, patients tend to prefer the PEG tubes. PEG tubes are surgically implanted directly into the stomach and pass through a small incision in the abdomen.

Treatment for esophageal dysphagia (low dysphagia) - surgical intervention is usually required.

• Dilation - if the esophagus needs to be widened a small balloon may be inserted and then inflated (it is then removed).
• Botulinum toxin (botox) - commonly used if the muscles in the esophagus have become stiff (achalasia). Botulinum toxin, a strong toxin, can paralyze the stiff muscle, reducing constriction.

If the dysphagia is caused by GERD the patient may be prescribed drugs that reduce stomach acid levels.