Dysphagia: General Considerations

Definition and EtiologyTop

Dysphagia is a symptom of progressive or intermittent swallowing difficulty in the passage of solids and liquids from the oral cavity to the stomach due to a structural abnormality or esophageal motility disorder. Dysphagia may present as difficulty with swallowing, drinking, chewing, eating, sucking, controlling saliva, taking medication, or protecting the airway. It is usually related to underlying medical or physical conditions but occasionally may have a psychological component.

Oropharyngeal dysphagia refers to difficulty in the formation of a food bolus, propulsion of the bolus towards the pharynx, and initiation of swallowing movements. Esophageal dysphagia refers to difficulty in transition of the food bolus through the esophagus to the stomach. Globus sensation is a functional disorder manifested by a sensation of a lump, tightness, or retained food bolus in the pharyngeal or cervical area in the absence of major organic causes (esophageal dysmotility and association with gastroesophageal reflux disease [GERD]). Functional dysphagia is a sense of solid and/or liquid food lodging, sticking, or passing abnormally through the esophagus without evidence of objective abnormalities. Odynophagia refers to pain with swallowing, usually esophageal and retrosternal, and may present in the oropharyngeal phase.

Dysphagia-associated symptoms may include heartburn, regurgitation, drooling, food or fluid retention in the oral cavity, sensation of food “sticking,” pain, coughing during or right after eating or drinking, weight loss, chest discomfort or pain, hematemesis, anemia, and respiratory symptoms. Food impaction is the most common cause for acute onset of dysphagia in adults. Aging-related mild esophageal dysmotility is rarely symptomatic.

1. Causes of oropharyngeal dysphagia:

1) Structural: Inflammation (stomatitis, pharyngitis, tonsillitis, abscess, syphilis); tumors (of the pharynx, tongue, floor of the mouth); compression by the surrounding structures (goiter, lymphadenopathy); severe degenerative lesions of the spine; foreign bodies; or previous cervical, laryngeal, or cranial surgery or radiation.

2) Neuromuscular disorders: Most frequently cerebrovascular disorders (ischemic stroke, thrombosis, intracranial bleeding), bulbar and pseudobulbar palsy, brain tumors, head trauma, sedating medications. Less frequently tabes dorsalis, neurodegenerative diseases, extrapyramidal syndromes (Parkinson disease, Huntington disease, tardive dyskinesia), peripheral neuropathy (diabetes mellitus, sarcoidosis, Sjögren syndrome, amyloidosis), connective tissue disease (systemic sclerosis, systemic lupus erythematosus, dermatomyositis), Guillain-Barré syndrome, diphtheria, botulism, radiation, poliomyelitis, myasthenia and myasthenic syndromes, or myopathy (oculopharyngeal muscular dystrophy, facioscapulohumeral muscular dystrophy, mitochondrial myopathy, myotonic dystrophy).

2. Causes of esophageal dysphagia:

1) Esophageal stricture: Erosive esophagitis (GERD, Zollinger-Ellison syndrome), eosinophilic esophagitis, carcinoma of the esophagus or cardia; esophageal diverticula (eg, Zenker diverticulum), caustic ingestions, postsurgical resection for esophageal or laryngeal cancer, drugs (eg, KCl, salicylates), radiation therapy for tumors located in the proximity of the esophagus, esophageal ring (Schatzki ring) or web, foreign bodies, lymphocytic esophagitis, or healing of pressure ulcers caused by a long-term indwelling nasogastric tube.

2) Esophageal motility disorders: Achalasia (type I, II, and III), esophagogastric junction outflow obstruction, distal esophageal spasm, hypercontractile esophagus (Jackhammer esophagus), ineffective esophageal motility, absent contractility due to systemic sclerosis or Sjögren syndrome, esophageal dysmotility due to diabetes mellitus, Chagas disease, or drugs (nitrates, calcium channel blockers, estrogens, methylxanthines).

3) Compression of the esophagus by the surrounding structures: Mitral valve disease, retrosternal goiter, mediastinal or bronchial tumor, paraesophageal hiatal hernia, or history of cardiac or thoracic surgery.

3. Causes of odynophagia:

1) Esophagitis: Infections caused by fungi (Candida, Histoplasma, Blastomyces spp), viruses (herpes simplex virus [HSV], cytomegalovirus [CMV], HIV), or bacteria (Mycobacterium tuberculosis); erosive causes (in the course of gastroesophageal reflux disease); radiation; mucosal membrane damage by irritant tablets (potassium preparations, doxycycline, bisphosphonates, nonsteroidal anti-inflammatory drugs [NSAIDs]).

2) Esophageal cancer.

3) Foreign body in the esophagus.

4) Esophageal burns caused by caustic substances.

4. Post–coronavirus disease 2019 (COVID-19) infection:

Impairment of oropharyngeal swallowing function and abnormal laryngeal findings were common in patients with severe COVID-19 treated in the intensive care unit (ICU).Evidence 1Low Quality of Evidence (low confidence that we know true effects of the intervention). Quality of Evidence lowered due to indirectness and imprecision. Osbeck Sandblom H, Dotevall H, Svennerholm K, Tuomi L, Finizia C. Characterization of dysphagia and laryngeal findings in COVID-19 patients treated in the ICU-An observational clinical study. PLoS One. 2021 Jun 4;16(6):e0252347. doi: 10.1371/journal.pone.0252347. PMID: 34086717; PMCID: PMC8177545. To avoid complications related to dysphagia in this patient group, it may be of importance to evaluate the swallowing function as a standard procedure, preferably at an early stage, before initiation of oral intake (see Fiberoptic Endoscopic Examination of Swallowing). After acute respiratory distress syndrome (ARDS), ~30% of intubated patients develop dysphagia with a consequent risk of aspiration pneumonia, delayed oral feeding, weight loss, and increased mortality. Patients not hospitalized present with milder illness and tend to follow patterns of globus, muscle tension, dysphonia, and hypersensitivity of the larynx associated with chronic cough.Evidence 2Moderate Quality of Evidence (moderate confidence that we know true effects of the intervention). Quality of Evidence lowered due to indirectness. Miles A, McRae J, Clunie G, et al. An International Commentary on Dysphagia and Dysphonia During the COVID-19 Pandemic. Dysphagia. 2022 Jan 4:1–26. doi: 10.1007/s00455-021-10396-z. Epub ahead of print. PMID: 34981255; PMCID: PMC8723823.

DiagnosisTop

Dysphagia and odynophagia are both alarming symptoms, especially if it has recently developed in an elderly patient and is rapidly worsening; in such cases promptly exclude cancer of the esophagus or cardia.

1. History and physical examination: Determine the type of dysphagia:

1) Oropharyngeal dysphagia is characterized by difficulty in the formation of a food bolus, its passage towards the pharynx, initiation of swallowing of liquids and solids, and sensation of residual food remaining in the pharynx or cervical region. Associated symptoms include dry cough, choking, throat discomfort, nasopharyngeal regurgitation, and aspiration. Pharyngeal dysfunction–induced dysphagia may be accompanied by dysphonia, sneezing, and lacrimation. Oral dysfunction–induced dysphagia may be associated with pain during swallowing, drooling, food spillage, sialorrhea, piecemeal swallows, and dysarthria.

2) Esophageal dysphagia is manifested by a sensation that food (initially solid food) is being obstructed at the suprasternal notch or retrosternal level for several seconds after initiating a swallow, distension or pressure in the chest, vomiting, cough and expectoration of saliva, and in some cases also by pain on swallowing.

2. Diagnostic procedures:

1) Upper gastrointestinal endoscopy is essential to confirm or exclude structural changes of the esophagus, esophagogastric junction, and stomach with histologic examination.

2) Barium radiography is performed to identify the cause of oropharyngeal dysphagia (fluoroscopic examination of the process of swallowing) and esophageal motility disorders, such as Zenker diverticulum, achalasia, Jackhammer esophagus, hiatal hernia, and GERD.

3) Esophageal high-resolution manometry with or without impedance study can confirm the diagnosis of esophageal motility disorders, such as different types of achalasia and Jackhammer esophagus.

4) Ambulatory esophageal pH monitoring with or without impedance study is used to exclude GERD. It also provides information on whether dysphagia is associated with acid exposure of the esophagus.

Complications and ConsequencesTop

Malnutrition and dehydration, aspiration pneumonia, compromised general health, chronic lung disease, choking, and even death may be a consequence of dysphagia. Morbidity related to dysphagia is a major concern. Adults with dysphagia may also experience lack of interest in or less enjoyment of eating or drinking and embarrassment or isolation in social situations involving eating. Dysphagia may increase burden to caregivers and require significant lifestyle alterations for the patient and the patient’s family.

Treatment and PrognosisTop

The treatment and prognosis of dysphagia depend on the nature of underlying conditions.