Literacy and Education May Prevent Dementia
Martin Prince et al at the King's College London's Institute of Psychiatry conducted a cohort study to evaluate the dementia incidence and mortality in the middle-income nations. The study was the largest of its kind and was published in the Lancet 2012.
A population-based cohort study was conducted on all individuals aged 65 years and above who lived in the urban region of Cuba, Dominican Republic, Mexico, Venezuela, Peru and China. In total about 12,800 people were enrolled for the study.
Information was obtained regarding age in years, educational level, sex, literacy, household assets, occupational attainments and mortality.
The information was used to analyze the incidence of dementia and to assess whether factors such as literacy and education provided safety against dementia development.
The study findings suggested that incidence of dementia in the middle-income nations was almost the same as in higher-income countries. The study highlighted an important fact that education provided considerable protection against dementia in both the less-developed and developed countries.
New cross-sectional approach for diagnosing dementia that is more sensitive in detecting mild to moderate dementia cases have revealed the dementia incidence to be 1.5 to 2.5 times greater than those detected by standard DSM-IV criteria.
Earlier studies using the popular western diagnostic approaches like the Diagnostic and Statistical Manual of Mental Disorders (DSM) have shown that the rate of dementia incidence might be significantly greater in low-and-middle income nations in contrast to high-income countries.
Professor Martin Prince stated, 'Our studies provide supportive evidence for the cognitive reserve hypothesis-that better brain development can mitigate the effects of neurodegeneration in later-life. Our findings suggest that early life influences, education and learning to read and write, may be particularly important for reducing the risk of dementia in late life. We need to understand more about cognitive reserve, how to measure it, and how it is stimulated across cultures.'
He further added, 'The high incidence of dementia in less developed countries reminds us that we are facing a global epidemic, and there needs to be more focus on prevention.'
In the beginning of the study the dementia affected people were predisposed to three-fold higher risk of dying as compared to dementia-free individuals. The study also revealed that 10/66 incidences of dementia were independently related to advancing age, low education level and being female. Occupational attainment has no association with dementia incidence.
It was concluded that literacy and education offered protection against dementia development. The experts said, 'The protective effects of education seem to extend to settings where many older people have little or no formal education, and literacy confers an additional independent benefit. These findings...support the notion that cognitive reserve might counter the effects of neurodegeneration later in life.'
Dementia incidence and mortality in middle-income countries, and associations with indicators of cognitive reserve: a 10/66 Dementia Research Group population-based cohort study; Martin Prince et al; The Lancet Online Publication 2012.