Diabetes mellitus (Type 2) linked to Alzheimer's disease
People with insulin resistance, or type 2 diabetes mellitus, may be at higher risk for developing plaques in the brain that are linked with Alzheimer's disease, a new study published in the August 25, 2010, issue of Neurology suggests.
Kensuke Sasaki, MD, PhD at Kyushu University in Fukuoka, Japan studied 135 people with an average age of 67 from Hisayama, Japan and found the association between high blood sugar levels and symptoms of Alzheimer's disease.
For the study, participants underwent several diabetes glucose tests for blood sugar levels and also monitored for symptoms of Alzheimer's disease over a period of 10 to 15 years. During that time, about 16 percent developed the disease.
After the participants died, researchers further examined their autopsied brains for signs of Alzheimer's disease by studying plaques and tangles. While 16 percent had symptoms of Alzheimer's disease while alive, plaques were present in a total of 65 percent of patients.
Those who had abnormal results on three tests of blood sugar control had an increased risk of developing Alzheimer's plaques, the researchers found.
Plaques were found in 72 percent of people with insulin resistance, compared to 62 percent of people who had no insulin resistance. Nevertheless, the study did not find a link between diabetes factors and tangles in the brain.
"Further studies are needed to determine if insulin resistance is a cause of the development of these plaques," said Sasaki. "It's possible that by controlling or preventing diabetes, we might also be helping to prevent Alzheimer's disease."
A health observer suggested that a blood sugar involved process called glycation may be implicated in the pathology of Alzheimer's disease.
One report published in 1998 in GLYCOCONJUGATE JOURNAL states that studies have suggested that formation of advanced glycation end products in some brain proteins are associated with Alzheimer's disease.
With insulin resistance or type 2 diabetes mellitus, people cannot handle blood sugar adequately; this results in high circulating blood sugar, which can fasten the glycation process.
By David Liu and editing by Rachel Stockton