What is Dysphagia
Dysphagia is a swallowing disorder characterized by difficulty moving food or liquid from the mouth to the stomach, which can lead to serious complications including aspiration pneumonia, malnutrition, dehydration, and increased mortality. 1
Definition and Classification
Dysphagia can be classified based on the phase of swallowing affected:
- Oral dysphagia: Difficulty with the voluntary preparation and propulsion of food in the mouth
- Pharyngeal dysphagia: Problems with the involuntary triggering of the swallow reflex
- Esophageal dysphagia: Difficulty with food passage through the esophagus 1
Alternatively, dysphagia can be categorized as:
- Oropharyngeal dysphagia: Affects the mouth and throat
- Esophageal dysphagia: Affects the esophagus 2
Pathophysiology
Dysphagia results from impairments in:
- Motor sequence planning
- Coordination and timing
- Anatomical structural displacement during swallowing 1
These impairments can lead to:
- Penetration: Food/liquid enters the laryngeal vestibule but doesn't pass below the vocal folds
- Aspiration: Food/liquid enters the trachea and lungs
- Silent aspiration: Aspiration without protective cough reflex (occurs in 55% of aspirating patients) 1
Causes
Dysphagia is not a disease itself but a symptom of various underlying conditions 1:
Neurological causes (most common for oropharyngeal dysphagia):
- Stroke (affects >50% of patients)
- Parkinson's disease
- Dementia
- Amyotrophic Lateral Sclerosis (30% at diagnosis, eventually all patients)
- Multiple Sclerosis (>33% of patients)
- Myasthenia gravis (15% at onset, >50% during progression)
- Traumatic brain injury 1, 3, 4
Structural causes:
- Esophagitis
- Achalasia
- Esophageal strictures
- Zenker's diverticula
- Cervical osteophytes
- Head and neck cancer
- Thyroid nodules 1, 3, 2
Other factors:
- Medical interventions (endotracheal intubation, tumor resection)
- Medications (anticholinergics)
- Age-related changes (presbyphagia) 1, 3
Clinical Presentation
Patients with dysphagia may present with:
- Food sticking in throat
- Coughing/choking during meals
- Globus sensation
- Nasal regurgitation
- Nasal-quality voice
- Food dribbling
- Difficulty initiating swallow
- Weight loss
- Recurrent pneumonia 1, 3
A reflexive cough during eating has 74% sensitivity and 74% specificity for aspiration in neurologically impaired patients 3.
Complications
Untreated dysphagia can lead to:
- Aspiration pneumonia: 3-fold increased risk in stroke patients with dysphagia 1
- Malnutrition: Due to reduced intake and increased metabolic demands
- Dehydration: A frequent and serious complication 5
- Reduced quality of life: Major long-term impact 1
- Increased mortality: Particularly in neurological conditions 1
Diagnostic Approach
The gold standard imaging studies for dysphagia evaluation include:
- Modified barium swallow: Evaluates oral and pharyngeal phases of swallowing 1, 3
- Videofluoroscopy: Assesses bolus manipulation, tongue motion, hyoid and laryngeal elevation 3
- Esophagram: Evaluates the entire esophagus (important as 68% of patients with dysphagia for solids have abnormal esophageal transit) 1, 3
- CT of the neck with IV contrast: Useful for assessing surgical hardware and postoperative anatomy 3
High-Risk Populations
Dysphagia is particularly prevalent in:
- Older adults (up to 22% in primary care setting)
- Adults over 65 (account for two-thirds of all dysphagia cases)
- Post-cervical spine surgery patients
- Patients with neurological disorders
- Patients requiring prolonged mechanical ventilation (70-80%) 1, 3
Dysphagia should be considered a geriatric syndrome due to its high prevalence and serious consequences in older adults 1.