Adult-onset dysphagia

Dysphagia presents with a vast array of aetiologies and is a common presenting complaint in the general practice setting.¹ In addition to being a potential symptom of malignancies, dysphagia represents a common chronic disability within our ageing Australian population.² Timely recognition and early management of dysphagia have been shown to improve patient outcomes and quality of life and to reduce hospitalisations from secondary complications.^3,4

Aim

This article provides an overview of dysphagia to support general practitioners (GPs) in terms of assessment, common treatment options and the recommended management pathways.

Epidemiology

Dysphagia is a complex anatomical and/or functional disruption of the aerodigestive tract resulting in a poor swallow.⁵

Causes of dysphagia can be broken down into two broad categories relating to the affected anatomical location – oropharyngeal or oesophageal dysphagia – and similarly by its pathophysiology either being a motility disorder or an obstructive disorder.⁵ A list of differential diagnoses and their categorisations can be found in Table 1.

Dysphagia carries a significant disease burden among our communities, with notably high morbidity and mortality rates,⁶ although global reports vary with population-based incidences estimated to be between 2 and 20%.^7,8 Australian-specific reports reflect these data, indicating that 20% of Australians aged >50 years experience dysphagia, which increases to up to 50% in those residing in long-term care facilities.^6,8 Aspiration pneumonitis was the leading cause of death in people with a disability living in New South Wales residential care facilities in 2016.⁹ Although multifactorial, risk factors in the geriatric population include previous strokes, dementia and occasionally motor neurone disease. Dysphagia is more prevalent in women than men across all age groups.^5,10
 

Overview and subtypes of dysphagia

Oropharyngeal dysphagia

Oropharyngeal dysphagia relates to either a dysmotility or a mechanical obstruction at or above the level of the upper oesophageal sphincter (UES).

Several neurological conditions can result in dysmotility. Central causes include cerebrovascular accidents (CVAs) and neurodegenerative diseases such as Parkinson’s disease and Alzheimer’s disease. Peripheral causes include diabetic neuropathy or myasthenia gravis.^11,12 CVAs are the leading cause of oropharyngeal dysphagia, and are also associated with a higher risk of aspiration due to an uncoordinated swallow and an inability to protect the airway. As a result, up to one-third of stroke survivors will develop aspiration pneumonia in their first month of recovery.¹³ Dysphagia related to neurological disorders is often chronic and can result in significant disability, especially within the institutionalised geriatric population.^14–16

The most common mechanical obstruction of the oropharynx includes benign or malignant lesions of the head and neck (H&N), strictures, post-radiation changes and external compressive pathologies (ie goitre, cervical osteophytes).

The most common malignancy of the oropharynx is squamous cell carcinoma (SCC), which accounts for >90% of H&N malignancies.¹⁷ These SCCs can be classified as non-human papillomavirus (HPV)-related SCCs, commonly associated with tobacco smoking and heavy alcohol use, or by HPV-associated SCC, which is steadily rising in incidence.¹⁸

Oesophageal dysphagia

Oesophageal dysphagia relates to dysmotility or a mechanical obstruction below the level of the UES. The most common mechanical obstruction is a stricture secondary to gastroesophageal reflux disease (GORD).¹⁹ Recurrent gastric acid reflux can result in oesophagitis, which can lead to benign peptic stricture development. Alternatively, GORD can also result in the dysplastic process of Barrett’s oesophagus due to chronic irritation.²⁰ This histological change is a precursor to the development of oesophageal adenocarcinoma, which might result in progressive dysphagia, typically a sign of advanced disease.

Oesophageal motility disorders can be divided into primary oesophageal disorders or systemic diseases with a secondary effect on oesophageal motility. Achalasia is the most common motility disorder and is characterised by incomplete relaxation of the lower oesophageal sphincter, resulting in oesophageal aperistalsis.²¹ Less common primary motility diseases include diffuse oesophageal spasm and nutcracker oesophagus.²² The most common secondary oesophageal motility disorders are scleroderma and diabetic autonomic neuropathy, with both affecting the contractility of the oesophagus and resulting in aperistalsis.²³

History-taking

A thorough history and examination is required for all patients with suspected dysphagia. Refer to Table 2 for a focused summary. For appropriate escalation and management, it is important to address two broad questions. First, whether the dysphagia involves the oropharyngeal or oesophageal region; and second, whether it is caused by a mechanical obstruction or a motility disorder.

Differentiating between locations

Oropharyngeal pathology will typically result in a delay in swallow initiation, coughing, choking or nasal regurgitation with food. Patients with oesophageal obstructions often have difficulty self-localising the level of obstruction; however, they might present with symptoms such as a catching sensation in the throat or the chest.²⁴ Important red flag symptoms associated with malignancy include odynophagia, otalgia, neck masses, unintentional weight loss and bloody expectoration.

Differentiating between mechanisms

The primary way to differentiate between an obstructive or a dysmotility disorder is by assessing for foods that trigger dysphagia. Motility disorders affect solid and liquid foods, whereas obstructive disorders are typically initially associated with solid foods and patients might report substituting their usual diet with pureed textured food. Many of the medications found in Table 3 can lead to and contribute to dysphagia.^25,26
 

Clinical examination

The examination begins with assessing the symmetry of the face, neck and oral cavity, followed by palpation of the neck and supraclavicular region. The oral examination is performed with a tongue depressor and a light source with careful attention to the tonsils, tongue and the floor of the mouth. The clinician should also perform a cranial nerve examination and identify global or focal neurological pathologies. A focused examination can be found in Table 4.

Investigations and management

The history and examination can reliably identify the location and mechanism of dysphagia, which then allows for targeted investigations and the appropriate referral pathway to be actioned. When obstructive oropharyngeal dysphagia is suspected, a referral to an ear–nose–throat (ENT) specialist should be made for a nasoendoscopy and biopsies, as required. Patients suspected of oropharyngeal malignancy also benefit from computed tomographic imaging of the neck and chest to assess for primary lesions and associated lymphadenopathy. Isolated enlarged lymph nodes require an ultrasound-guided biopsy for further histological assessment.

Any patient suspected of having oesophageal dysphagia must be referred to a gastroenterologist for an upper gastrointestinal endoscopy (UGIE) to exclude an oesophageal malignancy, with biopsies taken as required.²⁷ An UGIE will also assess for other benign obstructive pathologies.

Specialised investigation for motility disorders can be undertaken when mechanical obstructions are broadly excluded. A non-invasive study such as a barium swallow study is a helpful primary investigation that can be organised by the GP, which might demonstrate patterns of barium stasis within the oropharynx and oesophagus. Following this, more specialised testing can be considered. A speech pathologist can assist with further assessments of oropharyngeal motility disorders. They can organise specialised testing in the form of a video fluoroscope swallow study, which is a dynamic radiological assessment of swallow, assessed in a multidisciplinary fashion by both radiologists and speech pathologists.^28,29 Magnetic resonance imaging of the brain can help diagnose neurological diseases that might be contributing to oropharyngeal dysfunction. Certain gastroenterologists and general surgeons might arrange manometric testing to delineate between different oesophageal motility disorders. Table 5 describes the various investigations in detail.

Community management

Most presentations of dysphagia are secondary to reflux.³⁰ First-line treatments can be instituted with an empiric prescription of proton pump inhibitors and liquid antacids for at least eight weeks.^31,32 GPs should counsel the patient on lifestyle modifications such as head elevation during sleep, avoidance of late-night meals, and avoiding exacerbating foods.³³ Not only does tobacco smoking cause laryngopharyngeal irritation, it leads to many aetiologies of dysphagia and therefore cessation counselling should be provided. In patients without any red flags, a referral to a specialist should be made when the dysphagia persists.

There is a significant burden of disability related to chronic dysphagia and the associated risks of aspiration, malnutrition and dehydration. Speech pathologists can provide education on postural techniques and dynamic manoeuvres to protect the airway during ingestion, while also altering food consistencies appropriate to the degree of dysfunction.³⁴ Oral hygiene maintenance reduces the colonisation of gastric microbes in the oropharynx and can reduce the risk of aspiration pneumonia in vulnerable patients.^1,35 This can be ensured by educating patients on the importance of routine dental hygiene and review. Referral to a dietitian can help with maintaining appropriate caloric and fluid requirements, which need to be tailored around dietary restrictions. In addition to these risks, chronic dysphagia can also have significant social and psychological ramifications due to the inability to enjoy eating, as well as the lack of participation in social dining, and attention should be directed towards these emotions.² Overall, given the holistic implications of the disability, it is important that any counselling and management also involve families and carers.^36,37

In severe cases of chronic dysphagia, enteral feeding may be considered. Families should be counselled about the harms and limited benefits of long-term enteral feeding with a nasogastric or percutaneous gastrostomy tube, especially in those with advanced dementia.³⁸

Conclusion

Dysphagia is a challenging complaint to manage. The aetiologies are broad and complex and as such, patients need a multifaceted approach. These patients would benefit from the integration of speech pathologists, dietitians and primary and tertiary care specialists. This article provides primary physicians with a guided template of pathologies and investigations that might help narrow the diagnosis.

Key points

• The prevalence of adult-onset dysphagia in Australia will continue to rise with a rapidly growing ageing population.
• Chronic dysphagia is common in the geriatric population and is a serious risk factor for the development of aspiration pneumonia.
• A thorough work-up allows the GP to delineate between oropharyngeal and oesophageal dysphagia and proceed with the relevant referral to either a gastroenterologist or an ENT specialist.
• Red flags for urgent specialist referrals include history of head and neck malignancy, history of heavy alcohol or tobacco use, new onset of persistent hoarseness, unexplained weight loss, haemoptysis and haematemesis, otalgia, unrelenting pain and obstructive dysphagia.
• Incorporating allied health professionals such as speech pathologists, dietitians, nurses and carers into dysphagia treatment is vital to setting up safe-feeding measures.