General Medical Information

Olfaction And Gustation In The Elderly

Byron J. Bailey

The senses of smell and taste play important roles in the quality of life and the general state of health of older patients. They give food and beverages their special flavors and degree of palatability, and they serve to warn of the presence of dangerous volatile agents such as natural gas, fumes, and smoke. Aging is associated with specific morphologic changes such as loss of zonal distribution of receptor, sustentacular, and basal cells. Dilatation of Bowman glands and invagination of the respiratory epithelium into the lamina propria may occur. The area of the olfactory neuroepithelium may be reduced with replacement by respiratory epithelium. These processes increase with age and can be documented using instruments such as the University of Pennsylvania’s Smell Identification Test. Any infectious or inflammatory process can interfere with the access of odorant molecules to the olfactory epithelium or tastant molecules to the receptor cells in the taste buds. Degenerative diseases, drugs that decrease cell turnover, radiation therapy, viral infections, endocrine disorders, neoplasms, and trauma may account for the decrements in taste and smell observed in the elderly. Age-related changes in ability to smell and taste have been demonstrated. Unfortunately, the basis for these changes is not clear. The effects of aging may be a major component, but the interpretation of the observed functional decrement is clouded by the possibility that other factors are operating in these patients, such as the cumulative effects of repeated viral infections, medications, and poor oral hygiene and the onset of various other age-related diseases.