Older type-2 diabetes patients are at greater risk of cognitive impairment than their non-diabetic counterparts. They also are at a higher risk of brain atrophy, so control of the insulin levels is key to normal brain performance, and reduced levels of insulin could contribute to dementia progression, including Alzheimer’s disease.

The ACCORD trial, after 40 months of study on 3,000 diabetic patients, reported in the Lancet Neurology that lowering of a diabetic’s blood sugar 7-7.5% did not lead to cognitive decline. It does, however, lead to reduction of the risk of kidney disease, cardiovascular disease and eye problems. They were trying to see if the previous studies, that showed no problem with the levels reduction between 7-7.5% could even come out better if the reduction had been cut to 6%.

Smaller brain volume is linked to cognitive decline, and patients involved in the group undergoing intensive treatment showed a larger mean brain volume than those undergoing the standard treatment in the study. In all cases there was no decline in cognitive function.

A separate study, conducted by the Columbia University Medical Center, proves that blood sugar spikes take their toll on memory by affecting an area of the brain within the hippocampus that helps form memories – the dentate gyrus. “The ability to regulate glucose starts deteriorating by the third or fourth decade of life,” says lead investigator Dr. Scott Small, associate professor of neurology at Columbia. “If we conclude this is underlying normal age-related cognitive decline, then it affects all of us,” he added.

In the study, researchers used high-resolution functional MRI technology (magnetic resonance imaging) to map brain regions in 240 elderly subjects. They were able to find a correlation between elevated blood glucose levels and reduced cerebral blood volume, or blood flow, in the dentate gyrus, an indication of reduced metabolic activity and function in that region of the brain. By manipulating blood sugar levels in mice and monkeys, researchers said, they tried to confirm a cause-and-effect relationship between the glucose spikes and the reduced blood volume, Dr. Small said.

Researchers said the effects can be seen even when levels of blood sugar, or glucose, are only moderately elevated, a finding that may help explain normal age-related cognitive decline, since glucose regulation worsens with age.

Bruce S. McEwen, who heads the neuroendocrinology lab at Rockefeller University in New York, and was not involved in the research, said the study’s findings were “compelling,” with important implications not just for the elderly but for the growing number of overweight children and teens at risk of Type 2 diabetes.

This is Ron White, two-time USA Memory Champion , memory training expert, and memory keynote speaker. Control of diabetes and blood sugar will allow your brain to develop more synapse that will keep it in good memory order.




MemoryZine.com – Diabetics’ Cognitive Decline Not Slowed With Intensive Blood Sugar Control: http://memoryzine.com

New York Times – Blood Sugar Control Linked to Memory Decline, Study Shows: http://www.nytimes.com/2009/01/01/health/31memory.html