Older people who sleep too much or too little, and who do not read enough, may have an increased risk of suffering cognitive impairment, a new study suggests.

Cognitive impairment refers to problems with mental abilities, such as memory, language and planning. It is often seen as an intermediate stage between normal age-related cognitive decline and more serious cognitive problems, such as dementia.

Spanish scientists set out to investigate lifestyle factors that can affect cognitive impairment. They looked at 245 people over the age of 65, 12% of whom were found to have cognitive impairment.

They found that older people who slept less than six hours per night, or more than eight hours, had a 2.6 increased risk of developing cognitive impairment.

As a result, people who suffer with chronic insomnia or daytime sleepiness may face an increased risk, the scientists suggested.

Reading was another important risk factor. People who did not read at all were 3.7 times more likely to develop cognitive impairment, while those who only read occasionally were 2.5 times more likely to develop the problem.

Details of these findings were published in the Spanish journal, Revista de Investigación Clínica (Journal of Clinical Investigation).

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