TedHutchinson

[URL=http://www.eurekalert.org/pub_releases/2011-08/aaon-hbp072611.php]High blood pressure, diabetes, smoking and obesity in middle age may shrink brain, damage thinking[/URL]
[QUOTE]T. PAUL, Minn. – A new study suggests smoking, high blood pressure, diabetes and being overweight in middle age may cause brain shrinkage and lead to cognitive problems up to a decade later. The study is published in the August 2, 2011, print issue of Neurology®, the medical journal of the American Academy of Neurology.

"These factors appeared to cause the brain to lose volume, to develop lesions secondary to presumed vascular injury, and also appeared to affect its ability to plan and make decisions as quickly as 10 years later. A different pattern of association was observed for each of the factors," said study author Charles DeCarli, MD, with the University of California at Davis in Sacramento and a Fellow of the American Academy of Neurology. "Our findings provide evidence that identifying these risk factors early in people of middle age could be useful in screening people for at-risk dementia and encouraging people to make changes to their lifestyle before it's too late."

The study involved 1,352 people without dementia from the Framingham Offspring Study with an average age of 54.

Participants had body mass and waist circumference measures taken and were given blood pressure, cholesterol and diabetes tests. They also underwent brain MRI scans over the span of a decade, the first starting about seven years after the initial risk factor exam. Participants with stroke and dementia at baseline were excluded, and between the first and last MRI exams, 19 people had a stroke and two developed dementia.

The study found that people with high blood pressure developed white matter hyperintensities, or small areas of vascular brain damage, at a faster rate than those with normal blood pressure readings and had a more rapid worsening of scores on tests of executive function, or planning and decision making, corresponding to five and eight years of chronological aging respectively.

People with diabetes in middle age lost brain volume in the hippocampus (measured indirectly using a surrogate marker) at a faster rate than those without diabetes. Smokers lost brain volume overall and in the hippocampus at a faster rate than nonsmokers and were also more likely to have a rapid increase in white matter hyperintensities.

People who were obese at middle age were more likely to be in the top 25 percent of those with the faster rate of decline in scores on tests of executive function, DeCarli said. People with a high waist-to-hip ratio were more likely to be in the top 25 percent of those with faster decrease in their brain volume.[/QUOTE]

I think this follows on nicely from the previous blog which may give people the idea that there is nothing that can be done (if there is no single cause underlying Alzheimer's) to prevent it. This study is showing that if we identify and control in midlife those risk factors that are remediable, then we can prevent loss of cognitive function / memory in later life.

There really shouldn't be any difficulty in getting people to check there blood pressure and take sensible measures to reduce blood pressure BEFORE it leads to damage in the brain. We should be telling people that they may be able to delay worsening of decision making/planing/executive function by between 5 ~ 8 years simply by reducing high blood pressure. The sooner they start the longer the delay.

Those with a high waist to hip ratio (obesity) are in the top quarter of those most likely to display loss of executive function and rapid rate of cognitive decline. This is something we can alter by reducing the amount of refined carbohydrate and sugar/HFCS we eat. These processed foods also lead to diabetes and this report is telling us that developing diabetes in middle age also is associated with loss of brain volume, in the memory-forming hippocampus region, at a much faster rate than non-diabetics.

Similarly smoking is a risk factor we can eliminate. Smokers lost brain volume overall and in the hippocampus at a faster rate than non-smokers.

I think we need to be more proactive in encouraging others to identify risk factors early, before or while people are middle-aged and encourage them to make changes to their lifestyle then, before it's too late.

This is the study the press release above came from
[url=http://www.ncbi.nlm.nih.gov/pubmed/21810696]Midlife vascular risk factor exposure accelerates structural brain aging and cognitive decline.[/url]

Here is another press article by the lead author of the above research.
[url=http://seattletimes.nwsource.com/html/health/2015981629_alz24.html?prmid=obnetwork]Alzheimer's prevention as elusive as disease itself
Will a healthy lifestyle help prevent Alzheimer's disease, or at least delay its onset?[/url]
This is quite interesting as he puts some numbers on the risk factors.
[quote]Lack of exercise 21% of Alzheimer's in America, and high blood pressure 8 %, the study theorizes, while low educational attainment and midlife obesity might each cause 7%. Diabetes 3%.[/quote] I think that diabetes number is much lower than is true because diabetes is actually shortening folks lives. Dying sooner may be a way of reducing Alzheimer's incidence but not a route that I want to choose.

[url=http://www.medpagetoday.com/upload/2011/9/20/Neurology-2011-Ohara-1126-34.pdf]Glucose tolerance status and risk of dementia in the community :The Hisayama Study[/url] This paper puts some numbers on the increased risk of dementia from having a high blood glucose level.

[url=http://www.sciencedaily.com/releases/2011/09/110919163947.htm]Science Daily plain English report of study findings[/url] "people with diabetes were twice as likely to develop dementia as people with normal blood sugar levels."