Pathy's Principles and Practice of Geriatric Medicine. Группа авторов
in the elderly. Soergel et al. coined the term prebyesophagus in 1964 when reporting radiological and manometric observations in a group of nonagenarians.19 Only 2 of 15 subjects had ‘normal’ oesophageal motility, and on barium examination, there was a high prevalence of tertiary contractions, delayed clearance, and oesophageal dilatation. Manometry showed non‐peristaltic, multi‐peaked pressure waves. These subjects, however, could scarcely be described as healthy elderly, given the high prevalence of dementia and other chronic illnesses, including diabetes. Not surprisingly, more recent studies indicate that the prevalence and severity of oesophageal motor dysfunction in healthy ageing are less than suggested by early reports. A recent systematic review reported that in subjects over 60 years of age, UOS resting pressure was lower than in the young but also exhibited less swallow‐induced relaxation, indicative of a degree of UOS resistance.20 This would intuitively favour a prolongation of the oropharyngeal phase of swallowing and an increase in intra‐bolus pressure in the hypopharynx.21 While not clinically significant in the healthy elderly, these findings must be taken into account when evaluating swallowing studies in older patients with oropharyngeal dysphagia, where reference ranges derived from the young should not be used. Reflex responses of the UOS to oesophageal stimuli (increased pressure with oesophageal balloon distension and decreased pressure with air distension) appear to remain intact with healthy ageing, but reflex UOS contraction in response to laryngeal stimulation is impaired,22 which could predispose to aspiration. The fact that the frequency but not the magnitude of the response is diminished suggests that the sensory side of the reflex arc is impaired. In the distal oesophagus, studies in older patients have reported a reduced amplitude of contractions and a greater frequency of failed peristalsis than in the young,20 while secondary peristalsis is less easily elicited.23 Reductions in primary and secondary peristalsis, as well as changes in biomechanical properties (increased oesophageal stiffness), have been observed from as early as age 40.24
In the elderly, there is an increased prevalence of hiatus hernia (around 60% of those over 60),25 and both the resting pressure and intra‐abdominal length of the LOS decline with age, while acid exposure increases,26 all of which increase the risk of GORD. Other predisposing factors include reduced flow of saliva and impaired acid clearance. The frequency of transient LOS relaxations, the major mechanism of acid reflux in most individuals, has not been specifically studied in the elderly; nor have mucosal repair mechanisms been compared with those in the young. The number of reflux episodes appears similar in both age groups, but their duration may be more prolonged in the elderly,27 which may relate to impaired clearance mechanisms. The refluxate may also be less acidic due to a higher prevalence of atrophic gastritis in the elderly, but it should be recognised that its bile content may be important in mucosal injury (e.g. Barrett’s mucosa); and this has not been studied specifically in relation to age.28
Clinical presentation of disordered oesophageal motility
Disordered oesophageal motor function may present with symptoms of difficulty swallowing (dysphagia) or chest pain. In both nursing homes (50–60%) and general medical wards (10–30%), there is a high prevalence of dysphagia when patients are specifically questioned,29 although less than half of elderly subjects who reported dysphagia in a population‐based survey had consulted a physician about it. Potential consequences of dysphagia include aspiration, which contributes substantially to mortality, and inadequate intake of nutrition.
Swallowing disorders can be classified into those of oropharyngeal (difficulty initiating a swallow) or oesophageal (impaired transport of swallowed material) origin, and these can usually be discriminated with a careful history and examination. The oropharyngeal component of swallowing comprises preparatory (chewing food, mixing with saliva, and bolus formation), oral (propulsion of the bolus by the tongue and palate to the pharynx), and pharyngeal (transport through the UOS while protecting the airway) phases. A comprehensive discussion of dysphagia of oropharyngeal origin is included in Chapter 49.
Potential causes of oesophageal dysphagia are listed in Table 17.1 Key points in the history include whether dysphagia is for solids or liquids, whether it is intermittent or progressive, and whether there are associated reflux symptoms such as heartburn.30 Progressive difficulty in swallowing solids is suggestive of a structural lesion, while dysphagia for both liquids and solids is associated with motility disorders. Endoscopy provides a means to visualise and biopsy structural lesions and may also be therapeutic (for example, dilatation of a peptic stricture). Endoscopy and biopsy are also likely to be helpful when odynophagia (painful swallowing) is the presenting complaint, and in the patient with dysphagia can help exclude eosinophilic esophagitis, which is increasingly being recognised even in older patients.31 Barium videofluoroscopy provides complementary information regarding motor function as well as structural lesions, while manometry is of greatest use in confirming or excluding a diagnosis of achalasia.
Table 17.1 Oesophageal causes of dysphagia.
| Structural lesions |
| Neoplasm |
| Peptic stricture |
| Rings and webs |
| Vascular compression |
| Pill esophagitis |
| Reflux esophagitis |
| Eosinophilic esophagitis |
| Diverticula |
| Motility disorders |
| Achalasia |
| Distal oesophageal spasm and jackhammer oesophagus |
| Non‐specific motility disorders |
| Systemic disease (diabetes mellitus, progressive systemic sclerosis, Parkinson’s disease) |
Of the primary oesophageal motility disorders, the proportions of patients in different categories are similar in older (>60 years) and younger patients; but in older patients presenting with dysphagia, achalasia and distal oesophageal spasm are more commonly diagnosed in the older group.20 While the peak incidence of achalasia is in early to mid‐adulthood, a second, smaller peak occurs in the elderly.32 Oesophageal spasm is more commonly diagnosed over 50 years of age, while non‐specific motility disorders are particularly associated with an older population.
Achalasia
Achalasia is an oesophageal motor disorder of unknown aetiology, associated with incomplete or absent swallow‐induced LOS relaxation together with disordered oesophageal contractile activity.33 Inflammation of the myenteric plexus is an early histological finding, followed by ganglion loss and neural fibrosis. The condition typically presents with dysphagia for both liquids and solids, although weight loss, regurgitation, and aspiration may also be presenting symptoms, particularly in the elderly. Conversely, chest pain is reported less often in older than in young patients.
A barium swallow may show impaired peristalsis, delayed emptying, and dilatation of the oesophageal body (the latter more characteristic in the elderly than the young), with ‘bird’s beak’ or ‘rat’s tail’ tapering at the LOS (Figure 17.2). At manometry, the resting LOS pressure may be high or within the normal range, but LOS relaxation on swallowing is either absent or incomplete. Contractions of the oesophageal body can be either absent (type I) or simultaneous (type II), or there may be premature distal