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Part II Nutrition Assessment, Consequences, and Implications

swallow to having dysphagia. If dysphagia is diag- nosed, it can trigger a cascade of events that may lead to significant health disparities.

Dysphagia is defined as a dysfunction with any phase of the act of swallowing that results in the sensa- tion of food, fluid, or medications being delayed or hindered in the passage from the mouth to the stomach (9). The prevalence of dysphagia increases with age as well as in relation to the presence of common disease states found in the older adult population. Untreated dysphagia can lead to dehydration, malnutrition, respi- ratory infections, involuntary weight loss, depression, and death; therefore, it is an important component of all nutrition assessments (10).

PREVALENCE

It is difficult to quantify the prevalence of dysphagia due to the wide variety of indicators used to diagnosis it. Table 10.1 (see page 155) lists the causes of dyspha- gia in order of prevalence in the United States; note that as many as 70% of all cases are of unknown origin (10). Additionally, current review of the literature reveals a great disparity in recent evaluation of the fre- quency of dysphagia in various settings. From avail- able data, the prevalence of dysphagia in all adults is estimated to be between 6% and 9%, or approximately 1 in 25 adults (7,10). However, the incidence of dys- phagia is most common in older adults and correlates well with the presence of common diseases found in this population. Studies show the incidence of dyspha- gia among independent healthy adults 50 years of age can reach 22% and increase to 40% in those 65 or older (11-17), with a dramatic increase in prevalence seen in those 85 years and older. Frequency of dysphagia is thought to be exacerbated by reduced functional capa- bilities and incidence of disease and medication use. (See Box 10.3 [18,19].) Finally, the consequences of dysphagia are a diminished quality of life both socially (eg, embarrassment of coughing/choking at mealtimes) and physically (eg, food sticking in throat and chest).

TYPES OF DYSPHAGIA

There are two main forms of dysphagia: oropharyngeal and esophageal. Oropharyngeal dysphagia refers to the transfer or initiation of swallowing. Older adults who develop dysphagia primarily due to the aging process typically have oropharyngeal dysphagia. Esophageal dysphagia occurs in the body of the esophagus and involves the reduced ability to pass food to the stomach. This type of dysphagia usually is accompa- nied by coughing and choking secondary to aspiration and nasal regurgitation, leading to recurrent respiratory infections. The signs of dysphagia are noted in Box 10.4.

BOX 10.3 Medications Affecting Swallowing

Medications Resulting in Xerostomia ●

● decongestants antiemetics

● ● ● antiarrhythmics antihypertensives (eg, diuretics)

● opiates ●

● ● retinoids antipsychotics tricyclic antidepressants

● Selective serotonin reuptake inhibitors (SSRIs) ●

medications altering cognitive function/ alertness

● antianxiety ●

● ●

antihypertensives, especially centrally acting antiepileptics antiemetics

● benzodiazepines ● narcotics

● skeletal muscle relaxants

Medications Associated with Esophageal Injury ●

antibiotics ● ● ● ●

nonsteroidal anti-inflammatory drugs (NSAIDs)

acid-containing products antiarrhythmics aspirin

● bisphosphonates ●

iron-containing products ● methylxanthines ● potassium chloride ascorbic acid products

● ● other (eg, warfarin, diazepam, phenobarbital)

Source: Robbins J, Kays S, McCallum S. Team management of dysphagia in the institutional setting. J Nutr Elderly. 2007;26:59-104. Balzer KM. Drug induced dysphagia. Int J of MS Care. 2000;2(1):40-50.

Figure 10.1 (see page 150) depicts the risk factors for oropharyngeal colonization by respiratory patho- gens and aspiration pneumonia in older adults (20). Box 10.5 (see page 150) explains the causes of swallow dysfunction resulting in aspiration before, during, or after a swallow (21). Table 10.2 (see page

anticholinergics (eg, antihistamines; anti- Parkinson agents)