Diabetes: New Links to Alzheimer's
Researchers Say Diabetes Drugs Could Help Treat Alzheimer's Disease
July 17, 2006 -- Several new studies may help to clarify and strengthen the
link between diabetesand Alzheimer's disease,
according to researchers presenting their findings at the 10th International
Conference on Alzheimer's Disease and Related Disorders in Madrid, Spain.
What's more, the new research shows that some diabetes medications may
actually help treat and/or prevent the progressive brain disorder.
Affecting about 4.5 million Americans, Alzheimer's disease gradually
destroys a person's memory and ability to learn, reason, make judgments,
communicate, and carry out daily activities, according to the Alzheimer's
'Excitement' Among Researchers
The most common type of diabetes, type 2 diabetes, occurs when either the
body does not produce enough insulin or the cells ignore the insulin, according
to the American Diabetes Association. The body needs insulin to be able to use
Exactly how diabetes and Alzheimer's are linked is not fully understood, but
researchers are getting closer. One theory is that diabetes may cause blood
sugar to accumulate in the brain, which could damage brain cells.
"The excitement in the field is twofold," John C. Morris, MD,
director of the Alzheimer's Disease Research Center of Washington University in
St. Louis, tells WebMD. "There have been a lot of observational studies in
the field, but we don't yet understand how the link between Alzheimer's disease
and diabetes works, and understanding it better will give us insight into the
mechanisms of Alzheimer's disease," he says. "There are already
effective treatments for type 2 diabetes and it would be great if there were
this connection so we could take the drugs we use for type 2 diabetes to treat
or reduce the risk of Alzheimer's disease."
Prediabetes Ups Risk of Developing Alzheimer's
In one new study, Swedish researchers report that people with borderline
diabeteshave nearly a
70% increased risk of developing dementiaand Alzheimer's disease.
Researchers tracked 1,173 people aged 75 and older who were free of dementia
and diabetes at baseline. They identified borderline diabetes in 47 people.
Borderline or prediabetes occurs if a person has higher than normal blood sugar
levels that are not quite high enough to be diagnosed as type 2 diabetes.
What's more, this connection was present only among people who did not carry
the APOE ¦Å4 gene that increases risk for the most common form of Alzheimer's.
The risk for Alzheimer's was especially high when borderline diabetes occurred
with severe systolic hypertension(¡Ý180 mm Hg in the top number of a blood
pressure reading), the study showed.
Tight Control of Blood Sugar May Also Reduce Risk of Alzheimer's
Another new study presented here showed that people who already have type 2
diabetes have an increased risk of dementia and Alzheimer's disease.
Researchers, including Rachel A. Whitmer, PhD, of Kaiser Permanente's division
of research in Oakland, Calif., report that people with diabetes who had very
poor blood sugar control had the greatest risk, but "effective blood sugar
control may lower risk of another diabetes-associated complication --
dementia," they conclude in a written statement.