Robert W. Keefover
Eric D. Rankin
West Virginia University School of Medicine
Common misuse of the term senile as a synonym for demented reflects the fact that older people are at greater risk for intellectual impairment than are younger individuals. Although debate continues about whether or not cognitive decline is a normal response to senescence, increased vulnerability to many of the factors that promote mental deterioration is a reality of later life. As a result of observations such as those reported by Tomlinson and colleagues a quarter of a century ago ( Tomlinson, Blessed, & Roth, 1970), the vaguely defined concept of senile dementia ( Robbins & Angell, 1978) has gradually been abandoned. Instead, it is now recognized that severe mental deterioration (i.e., dementia) occurs in the older people only in the presence of specific disease states; Alzheimer's disease (AD) being the most common of these ( Katzman, 1986). In this context, we now view older people as more vulnerable to cognitive decline because they are at greater risk of developing many of the illnesses that cause it.
Some older people experience intellectual impairment in the absence of identifiable disease. Although these deficits do not typically justify a diagnosis of dementia, they may, nonetheless, detract from an individual's quality of life. Such cases are often attributed to poorly understood nonillnesses, such as Age-Associated Memory Impairment or may manifest as a consequence of psychosocial factors. In some cases, they appear to reflect the aging process itself. Like the dementing illnesses, however, these more subtle mental impairments occur more frequently in later life because of age-dependent increases in vulnerability to certain risk factors.
The terms intellectual, mental, and cognitive impairment are used interchangeably here in reference to any deterioration in the proficiency