Diabetes can cause memory loss in the old

A new study has found that diabetes could result in memory loss, depression and other types of cognitive impairment in older adults. A team led by Beth Israel Deaconess Medical Centre (BIDMC) neurophysiologist Vera Novak, MD, PhD, has identified a key mechanism behind this course of events after five years of study. They found that in older patients with diabetes, two adhesion molecules - sVCAM and sICAM - cause inflammation in the brain, triggering a series of events that affect blood vessels and, eventually, cause brain tissue to atrophy. Importantly, they found that the gray matter in the brain's frontal and temporal regions - responsible for such critical functions as decision-making, language, verbal memory and complex tasks - is the area most affected by these events. "In our previous work, we had found that patients with diabetes had significantly more brain atrophy than did a control group," explained Novak, Director of the Syncope and Falls in the Elderly (SAFE) Program in the Division of Gerontology at BIDMC and Associate Professor of Medicine at Harvard Medical School. "In fact, at the age of 65, the average person's brain shrinks about one percent a year, but in a diabetic patient, brain volume can be lowered by as much as 15 per cent," she stated. This discovery now provides two biomarkers of altered vascular reactivity in the brain. "If these markers can be identified before the brain is damaged, we can take steps to try and intervene," said Novak, explaining that some data indicates that medications may improve vascoreactivity. The study has been published in the November 2011 issue of the journal Diabetes Care.