Ageing and the brain

Ageing and the brain - http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2596698/

Conclusion

That the brain changes with increasing chronological age is clear, however, less clear is the rate of change, the biological age of the brain, and the processes involved. The brain changes that may affect cognition and behaviour occur at the levels of molecular ageing, intercellular and intracellular ageing, tissue ageing, and organ change. There are many areas of research under investigation to elucidate the mechanisms of ageing and to try to alleviate age associated disorders, particularly dementias that have the biggest impact on the population. In terms of personal brain ageing the studies suggest that a healthy lifestyle that reduces cardiovascular risk will also benefit the brain. Medical care in this area may even offer limited protection in terms of cognitive decline but this needs to be shown for antihypertensives, antiplatelet, and anticholesterol agents. It is also important to take note of the limitations in studies on the ageing brain. Many studies are cross sectional in nature, have small numbers of participants with wide ranges in chronological age, lack control for risk factors or protective factors, take no account of education that may improve performance on cognitive tests, and finally lack assessment with regard to depression that may also affect performance. It must be remembered that the brains of an elderly group may show cohort effects related to wider environmental influences, for example, lack of high energy foods while growing up.² It is also extremely difficult to separate out and measure single cognitive processes to fully understand any changes.¹⁰⁶

Future studies need to take full account of these factors and “cross sequential”, a combination of cross sectional and longitudinal studies, have been proposed.³ It is clear that our understanding of the ageing brain continues to grow but still requires much research that is especially important given the numbers of elderly people in society and their potential levels of cognitive impairment. Where appropriate, randomised controlled trials of therapeutic measures may, in future, lead the way to greater understanding.

Go to:

Abbreviations

AD - Alzheimer's disease

WML - white matter lesion

VaD - vascular dementia