Illiteracy and cognition in older adults.

Sir,

The article “Cognitive dysfunction in normally aging urban older adults” by Tripathi and Tiwari (2011) which appeared in volume 33 (2)[1] is interesting and has raised important issues regarding cognitive assessment in the elderly population. In this study the sample comprised of 89 community-dwelling normal elderly and most of the subjects (68.5%) had education below primary school level. Further, their results indicated that normal elderly had dysfunction in the domains of orientation and concentration. However, the findings of the article raise several questions for further examination. Here we have provided our observations in brief.

To the best of our knowledge no age and education adjusted cut off value is available on MMSE or HMSE to call someone ‘normal’ in Indian context. Moreover the cut off scores on these screening tools are meant to indicate probable impairment rather than determination of “normal aging” Secondly, it would have been useful if authors had provided more detailed information on education levels in terms of illiteracy and functional illiteracy, as it affects the performance on neuropsychological assessment and interpretation of the result. In clinical settings it is often observed that some elderly, although educated upto primary level, become functionally illiterate when they do not utilize their reading and writing skills. These skills may be redundant for their lifestyle or occupation, which is often the case in rural setting. Further it has been demonstrated that the ability to read and write itself reinforces and modifies our cognitive abilities.[2]

In Tripathi and Tiwari's study the majority of the sample had education below 5 years. Several studies have demonstrated that low education levels adversely affect the performance on neuropsychological tests.[34] This could be due to lack of exposure to psychological test and testing situation itself. Therefore, the poor performance on a particular test may not reflect the true cognitive ability on the tested domain, particularly when the tests are not culturally appropriate. Hence, we would be cautious in using the term “cognitive dysfunction” in the current study context.

Based on the performance on serial subtraction, orientation to time, month and date the authors have interpreted that normal elderly have cognitive impairment in the domains of orientation and concentration. It is well documented that subtests such as serial subtraction, orientation to time, month and date are influenced by education.[56] Also the elderly with low levels of education may perform poorly on a particular test even when they do not have deficit in that particular cognitive domain.

Poor performance in individuals with low education could be attributed to various reasons such as task familiarity and appropriateness of the test for given population, anxiety-related to testing situation, test taking attitude, lack of ecological validity of the test for population of individuals with low levels of education. It is therefore imperative to use ecologically valid and culturally appropriate tests in order to make definitive comments on the true cognitive status of a particular individual.