Chapter 1 Nutrition in Older Adults: An Overview

TABLE 1.1 Age-Related Changes in Gastrointestinal Anatomy and Physiology Location

Alterations Oropharynx

Xerostomia Altered protective reflexes Poor dentition, periodontal disease Altered taste perception Decreased olfactory discrimination

Esophagus

Reduced resting upper esophageal sphincter pressures Reduced lower esophageal sphincter relaxation Upward lower esophageal sphincter displacement into chest Delayed esophageal emptying with “tertiary” contractions Decreased contraction velocity and duration Reduced myenteric ganglion cells Increased amplitude of distal contractions Thickening of smooth muscle layer

Stomach Pancreas

Decreased mucosal prostaglandin, sodium, bicarbonate, and mucous secretion Possible delayed emptying of liquids and solids

Increased gallstone formation Decreased glucose tolerance Insulin secretory defects Decreased beta-cell sensitivity to incretin hormones Impaired beta-cell compensation with glucose load

Liver

Small intestine Colon

Ano-rectum

Decline in organ volume and blood flow Reduction in metabolic capacity Reduced hepatic drug clearance of rapidly cleared drugs

Possible decreased small bowel transit No significant primary changes

Reduced rectal compliance Impaired rectal sensation Decreased sphincter pressures Increased constipation Increased fecal incontinence

Source: Adapted from Firth M, Prather CM. Gastrointestinal motility problems in the elderly patient. Gastroenterology. 2002;122:1689, with permission from American Gastroenterological Association.

Oral Health/Teeth

Poor dentition and periodontal disease affect a signifi- cant number of older adults. An average of 25% of older women and 24% of older men are edentulous, with slightly over 32% of those 85 years of age or older reporting that they have no natural teeth. Lack of teeth is tied to socioeconomic status, with 42% of older adults with a family income below the poverty line reporting lack of teeth compared to 22% of older adults above the poverty threshold (1). Rates of oral cancer

increase with age, and prognosis is poor. Poor oral health in older Americans contributes to increased pain and suffering and to impaired sensory perception, mas- tication, and appetite; it can also significantly alter the nature and quality of food and fluid consumed. Other factors such as poverty and an inability to access or prepare food and to eat independently fre- quently contribute to poor food intake. Psychological factors such as cognitive or emotional impairment, home- lessness, and/or substance abuse are also possible

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