What is Dysphagia?
Dysphagia is a swallowing disorder characterized by subjective awareness of difficulty during passage of a liquid or solid bolus from the mouth to the stomach, or the perception of obstruction during swallowing. 1
Definition and Core Concept
Dysphagia represents both a symptom and a disorder that may be caused by structural and functional abnormalities affecting the oral cavity, pharynx, esophagus, and gastric cardia. 1 The condition involves disruption of the sophisticated, integrated sensorimotor swallowing system. 2
Epidemiology and Clinical Significance
- Dysphagia affects up to 22% of adults in primary care settings, with higher prevalence in older populations. 1
- Adults over 65 years account for up to two-thirds of all people with dysphagia. 1
- Among independently living elderly persons, 16% of those aged 70-79 years and 33% of those aged 80+ experience dysphagia. 3
- Oropharyngeal dysphagia occurs in up to 50% of elderly people and 50% of patients with neurological conditions. 4
Two Major Categories
Oropharyngeal Dysphagia
Oropharyngeal dysphagia is characterized by immediate difficulty initiating swallowing with symptoms in the mouth and throat. 5
Key features include:
- Difficulty starting to swallow, with problems evident in the oral or pharyngeal phase 5
- Coughing or choking during swallowing (indicating laryngeal penetration or aspiration) 1, 5
- Nasal regurgitation or nasal-quality voice (due to soft palate insufficiency) 1
- Wet or "moist" voice after swallowing (suggesting residue in the pharynx) 5
- Food dribbling from the mouth 1
- Globus sensation with a lump in the throat 1
- Sialorrhea and poor management of secretions 5
Esophageal Dysphagia
Esophageal dysphagia is characterized by a sensation of food getting stuck several seconds after swallowing, localized to the retrosternal or epigastric region. 5
Key diagnostic pattern:
- Dysphagia that starts with solids and progresses to liquids suggests mechanical obstruction (strictures, rings, malignancy). 5, 6
- Dysphagia for both solids and liquids from the start suggests a motor disorder (achalasia, diffuse esophageal spasm). 5, 6
- Symptoms are typically perceived in the chest or retrosternal area 5
Critical Clinical Pitfall: Silent Aspiration
In one study of 2,000 patients evaluated with videofluoroscopic examinations, 51% were found to aspirate; however, of those who aspirated, 55% demonstrated silent aspiration with an absent protective cough reflex. 1 This means many individuals have asymptomatic swallowing disorders and may present with signs of aspiration, pneumonia, weight loss, or malnutrition rather than dysphagia complaints. 1
Common Etiologies
Neurologic Causes
- Stroke, dementia, Parkinson's disease, amyotrophic lateral sclerosis, myasthenia gravis 1, 2
- Multiple sclerosis (affects more than one-third of patients) 3
- Neuromuscular and degenerative disorders 1
Structural Causes
- Esophageal strictures, rings, webs, diverticula 6, 7
- Malignancy (esophageal cancer) 5, 6
- Zenker's diverticulum 6
Inflammatory/Mucosal Causes
- Gastroesophageal reflux disease (affects 8-19% of adults with endoscopic findings) 3
- Eosinophilic esophagitis (occurs in up to 17% of certain populations) 3
- Dermatologic conditions (pemphigus vulgaris, lichen planus) 6
Iatrogenic Causes
- Anticholinergic medications can cause or exacerbate dysphagia through multiple mechanisms. 6, 3
- Neuroleptics can aggravate or cause dysphagia by affecting different components of swallowing 8
- Acetylcholinesterase inhibitors can worsen swallowing difficulties by increasing saliva production 3
Important Clinical Distinction
Abnormalities of the mid or distal esophagus or gastric cardia may cause referred dysphagia to the upper chest or pharynx, whereas abnormalities of the pharynx rarely cause referred dysphagia. 1 This means patients with pharyngeal symptoms should have their entire esophagus and gastric cardia evaluated. 1