On the Question of the Mental State of Centenarians

Abstract

The number of individuals over age 100 years in the United States will increase from 25,000 in 1986 to more than 108,000 by the year 2000. Despite this expected growth there is almost no information about their intellectual function. This is unfortunate since the study of centenarians offers valuable insight into the effects of aging upon the central nervous system. It may also clarify whether Alzheimer''s disease represents premature aging. To better understand their mental state, I evaluated 20 centenarians (17 women and 3 men) with a mean age of 101.75 years. The group completed on average 6.6 years of education and each had 4 illnesses and took 3.5 prescribed drugs. Eighty percent were in nursing homes, mostly due to inadequate social supports. Caregivers had thought that the majority were not demented. During evaluation, 75% had impaired vision while half had disturbed hearing. The speed of thought and body movement were slowed significantly. Centenarians had poor awareness of their environment, in general (p = 0.0019) and had impaired judgement (p = 0.006). Additionally, only 3 individuals had a history and examination to suggest Alzheimer''s disease. Unfortunately, the Folstein Mini-Mental State Exam (MMSE) and the Washington University Clinical Dementia Rating (CDR) were often difficult to score. Mean scores for the MMSE of 7.5 (1 standard deviation, 7.134) and the CDR of 2.08 (1.07) suggested dementia. These observations suggest that impaired intellectual function may be common in this group but there are several limitations on evaluating and interpreting such data.