History taking is the most important part of finding the cause of dysphagia. The first step is to decide whether the trouble lies in the mouth and pharynx (oropharyngeal dysphagia) or in the esophagus (esophageal dysphagia). The main questions are where the dysphagia is felt, the circumstances in which it occurs, the symptoms that accompany it, and how it has progressed; the presence of any alarm features then decides how urgently to act.
Location
Dysphagia felt around the suprasternal notch could be either oropharyngeal or esophageal dysphagia, because about 30% of distal esophageal dysphagia is referred to the proximal regions. Dysphagia felt around the chest is more reliably esophageal.
Circumstances
The setting narrows the cause. Patients who are immunocompromised or have AIDS are more prone to esophagitis (inflammation of the esophagus) from Candida, herpes simplex virus, cytomegalovirus or Kaposi sarcoma, each of which can lead to dysphagia. Pill-induced esophagitis is another circumstance, and opioids can add to dysphagia by slowing esophageal motility.
Associated symptoms
The accompanying symptoms often point to a level or a lesion. Nasal regurgitation (food coming back up into the nose) and pulmonary aspiration (food entering the airway and lungs) can happen in oropharyngeal dysphagia, and they are accompanied by coughing. A severe cough after swallowing is a sign of a fistula, an abnormal connection between the airway and the esophagus.
The order of symptoms also matters. Hoarseness followed by dysphagia points to a laryngeal lesion, whereas dysphagia followed by hoarseness points to involvement of the recurrent laryngeal nerve (the nerve to the voice box) by a malignancy. When dysphagia follows heartburn, a peptic stricture (a narrowing from reflux scarring) is most likely, and less frequently an esophageal adenocarcinoma.
Progression
The time course is one of the strongest clues. Dysphagia that lasts weeks to months and progresses during its course raises concern for neoplasia, and a short history before presentation is itself a warning sign. Dysphagia that is episodic and only slowly progressive over years raises concern for benign conditions such as Schatzki’s ring or eosinophilic esophagitis.
Alarm features
Certain findings mark a higher risk of a poor outcome and call for urgent investigation rather than observation: age over 50, gastrointestinal bleeding, odynophagia (painful swallowing), weight loss, vomiting, anemia and an abdominal mass. About 60% of patients with dysphagia have at least one such additional feature, and the combination of dysphagia with age over 50 and weight loss raises the risk of esophageal cancer further.