Health Articles

A major obstacle to the advancement of geriatric gastroenterology is our ignorance of the basic science of aging. This handicap is analogous to doing research in infectious disease without having the basic science of bacteriology. Nevertheless, some progress has been made in understanding the effects of aging on Gl physiology and pathophysiology.
The primary functions of !he GI system arc digestion and absorption; the secondary functions that subserve these activities are secretion and motility. Throughout life, the gut is constantly and rapidly changing. Epithelial cell turnover occurs as often as every 24 to 48 h. Absorption and secretion are almost constant. Myoelectric and motor activity arc continuous.
Aging is associated with physiologic and pathophysiologic changes in many organ systems (eg, endocrine, vascular, nervous) that affect Gl structure and function and produce variations in the presentation of GI illness. Aging also allows for the superimposition of altered alimentary function by extraintestinal diseases. When such diseases are common, the observed changes may appear to result from the aging process. A prime example is the esophageal motility changes in octogenarians that for decades were assumed to result from age-determined esophageal muscle changes. Recently, these changes have been shown to result from extraintestinal disorders (eg, diabetes niellitusand neurologic and vascular changes that supervene with age). In fact, research has shown that most age-related changes in GI motility result from neurologic rather than muscular changes.
The intricate interaction among psychologic and social stress and physiologic function is especially pertinent in the elderly, who arc subject not only to the usual stresses of adulthood but also stresses such as loss of spouse, family members, friends, and job at a lime of increasing mental and physical limitations. The interplay of psychosocial stresses and anatomic, motor, and secretory changes often leads to Gl symptoms, sometimes atypical ones. Some patients deny or downplay their GI symptoms: others exaggerate them.
Constipation, incontinence, and diverticular disease are the most commonly recognized GI problems in the elderly. Each has different underlying causes, and the specific pathogenesis dictates specific treatment.
Age may alter the presentation of malabsorption, and chronic diarrhea may affect an older patient differently and more severely than it affects a younger patient. For example, the increased incidence of nutritional deficiencies among (he elderly makes them particularly vulnerable to the effects of malabsorption. Also, the concentration of the brush border enzyme, lactase, decreases gradually with age. increasing lactose intolerance and intestinal gas and diarrhea. When malabsorption is superimposed, the symptoms are augmented. This situation is particularly bothersome when the patient has associated disabilities, such as a mobility disorder that makes reaching the bathroom difficult. If incontinence is also present, the foul-smelling, pasty steatorrhea is much less tolerable than [he odor of otherwise normal stool. Besides diarrhea from lactase deficiency, osmotic diarrhea caused by laxatives is common among the elderly and readily leads to dehydration, particularly because (he thirst mechanism may be impaired.
Cancer of various intestinal organs is common in elderly persons, and special considerations are required for successful surgical management. For example, elderly patients may have arthritis, stroke, or other impairments of dexterity, which may interfere with proper management of colostomies and ileostomies. Benign lesions in the elderly also require a specialized approach. Klderly patients are more fragile, and they often have coexisling cerebrovascular, cardiovascular, renal, or hepatic disorders thai increase their risk for any type of surgery. Nevertheless, treatment of brisk Gl bleeding should not be delayed in the elderly, who do not tolerate prolonged bleeding as well as younger persons.
Diagnostic approaches are also influenced by aging. When undertaking diagnostic studies or therapeutic regimens, the physician musl take into account the special needs of the elderly. A number of factors must be considered in deciding on the advisability of endoscopy and in determining the appropriate preparation and techniques. When determining the premedication requirement for endoscopy, the physician must consider the increased sensitivity to sedatives and analgesic medication and Ihe susceptibility to respiratory depression and hypotension. Careful monitoring is essential. Also. Ihe lateral rather than Ihe supine position must be maintained to minimize the risk of aspiration.