Jan 6, 2012

Cognitive Decline Sets In as Early as Age 45

The brain’s capacity for memory, reasoning and comprehension skills (cognitive function) can start to deteriorate from age 45.

By Bob DeMarco
Alzheimer's Reading Room

Cognitive Decline Sets In as Early as Age 45 | Alzheimer's Reding Room
Many of you won't like or enjoy reading this research. This is not one of those studies where there is a very small sample.

The subjects, 7,390 of them, were studied and tested over a ten year period.

Bottom line? Cognitive skills like memory and reasoning begin declining as early as age 45.

This reminded me of an article I first published back in 2009, Worried about Alzheimer's?

I was claiming "you can prevent Alzheimer's" in that article. The point I was trying to make is that you might actually be able to "delay" the onset of Alzheimer's by taking better care of yourself and doing the "right kinds of things".

I know this is going to sound harsh, but if you do the right kinds of things, you might die before Alzheimer's sets in. Something to think about.

Read the research synopsis below, or follow the link for the detailed study.

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Cognitive decline can begin as early as age 45, warn experts

The brain’s capacity for memory, reasoning and comprehension skills (cognitive function) can start to deteriorate from age 45, finds research published on bmj.com today.

Previous research suggests that cognitive decline does not begin before the age of 60, but this view is not universally accepted.

Archana Singh-Manoux
Researchers, led by Archana Singh-Manoux from the Centre for Research in Epidemiology and Population Health in France and University College London in the UK, argue that “understanding cognitive ageing will be one of the challenges of this century,” especially as life expectancy continues to rise.

They add that it is important to investigate the age at which cognitive decline begins because medical interventions are more likely to work when individuals first start to experience mental impairment.

Therefore the authors observed 5,198 men and 2,192 women over a 10-year period from 1997. They were all civil servants aged between 45 and 70 and were part of the Whitehall II cohort study established in 1985.

Participants’ cognitive functions were assessed three times over the study period. Individuals were tested for memory, vocabulary and aural and visual comprehension skills. The latter include recalling in writing as many words beginning with “S” (phonemic fluency) and as many animal names (semantic fluency) as possible.

Differences in education level were taken into account.

The results show that cognitive scores declined in all categories (memory, reasoning, phonemic and semantic fluency) except vocabulary and there was faster decline in older people.

The findings also reveal that over the 10-year study period there was a 3.6% decline in mental reasoning in men aged 45-49 and a 9.6% decline in those aged 65-70. The corresponding figures for women were 3.6% and 7.4%.

The authors argue that robust evidence showing cognitive decline before the age of 60 has important ramifications because it demonstrates the importance of promoting healthy lifestyles, particularly cardiovascular health, as there is emerging evidence that “what is good for our hearts is also good for our heads.”

They add that targeting patients who suffer from one or more risk factors for heart disease (obesity, high blood pressure and high cholesterol levels) could not only protect their hearts but also safeguard them from dementia in later life.

In an accompanying editorial, Francine Grodstein, Associate Professor of Medicine at Brigham and Women’s Hospital in Boston, says the study “has profound implications for prevention of dementia and public health.”

She adds that more creative research, perhaps using telephone and computer cognitive assessments, needs to be undertaken.

Timing of onset of cognitive decline: results from Whitehall II prospective cohort study

Research: Archana Singh-Manoux, INSERM Centre for Research in Epidemiology and Population Health, Hôpital Paul Brousse, Villejuif, France

Editorial: Francine Grodstein, Associate Professor of Medicine, Department of Medicine, Brigham and Women’s Hospital, Boston, MA, USA

Original content Bob DeMarco, the Alzheimer's Reading Room