Cognitive assessment in severe dementia and lower levels of education: reducing negligence

Abstract

Dementia is a devastating age-associated syndrome which is highly prevalent among the elderly, and an increasing problem with regard to public health costs and the use of services. The prevalence of dementia was of 24.3 million in 2001, and the estimate for the worldwide increase of new dementia cases every year is 4.6 million 1 . Furthermore, two thirds of the dementia patients live in low-and middle-income countries placing South America and Brazil at the top of the problem.Because a growing proportion of older adults with dementia (and particularly Alzheimer disease -AD) are surviving to more advanced stages of the illness it is estimated that onethird of dementia patients are in severe stages 2 . Evaluating from other sources of patients, almost half of community-dwelling patients and around 60% of institutionalized residents with dementia are in moderate or severe stages of the disease 3 . Additionally, severe dementia represents a major problem from the point of view of public health because it is always accompanied by marked functional impairment and frequent psychiatric and behavioral problems, often associated with marked loss of autonomy.Despite all these facts much research attempts and clinical attention have been directed towards early diagnosis, mild and prodromal stages of this condition, leaving severe dementia relatively neglected. At any rate, the information on cognition of these patients is still based on a relatively small amount of data compared to those on earlier stages of dementia. A partial explanation of the paucity of data is the floor effect reached by most used tests. Few neuropsychological tests are currently available for this purpose, such as the Test for Severe Impairment . Nonetheless, these instruments require a considerable amount of time and specialized training to administer, consequently they are not practical for brief assessment. The Mini-Mental State Examination (MMSE) is the most widely used tool for brief cognitive assessment, due to its simplicity and reliability 7 . However, this test shows a significant floor effect 8 for patients in more advanced stages of dementia, limiting its use in the evaluation of this specific sub-group. For this reason and based on the MMSE, Harrel and associates in 2000 developed the Severe Mini-Mental State Examination (SMMSE). The SMMSE is a brief assessment that requires minimal training and no special materials.Other important aspect of the investigation of cognitive assessment in severe dementia is that most of the studies with these instruments were developed with patients of high educational level. Studies on impact of low levels of education in severe dementia patients and instruments for the assessment of cognitive abilities in these patients are even fewer. In Brazil, Wajman and Bertolucci 9 have compared the performance in the severe MMSE with a set of instruments as well as age, education, and disease duration in a sample of fifty moderate to severe probable AD patients in moderate. In conclusion, they found the severe MMSE an...

Clinical characteristics and diagnostic accuracy of the revised Addenbrooke Cognitive Examination (ACE-R) in older adults with a low educational level

“…The increase in life expectancy in Brazil has been associated with a higher prevalence of age-related mental conditions such as Alzheimer's disease (AD) 1,2 . Brazil is one of 10 countries with the largest population of older adults in the world (WHO-UN).…”

“…Despite the large proportion of older adults who are either illiterate or with low levels of schooling in Brazil (20.4%), there is great controversy about reliable approaches for cognitive assessment of this population. Previous studies have sought to establish valid cutoff scores for illiterate adults 1,2 , but there is no consensus on whether data can be replicable in populations from different regions nationwide. Sociocultural aspects, e.g., living in rural areas and having limited access to the internet, banking services and public transportation, may influence cognitive performance 19 .…”