Manage type 2 diabetes to reduce risk of Alzheimer’s

By Dr. Ananya Mandal, MDApr 15 2011

A new study from a team of Chinese researchers has shown that controlling type 2 diabetes symptoms may produce many health benefits including a decreased risk of Alzheimer's disease.

The researchers from the Third Military Medical University in Chongqing, China have written in the latest issue of the journal Neurology that individuals with type 2 diabetes, high blood pressure and high cholesterol who sought treatment for these conditions were significantly less likely to develop Alzheimer's disease. Earlier studies have shown that individuals with poor cardiovascular and metabolic health are more likely to experience cognitive impairment as they grow older. However, the present investigation is among the first to indicate that treating these conditions reverses this risk.

For the study, researchers examined 837 individuals who already showed signs of mild cognitive decline, which is characterized by occasional memory problems and is thought to precede Alzheimer's disease. Half of the group also had at least one cardio-metabolic risk factor, including type 2 diabetes, high blood pressure or unhealthy cholesterol levels. All subjects completed tests of mental ability and submitted full medical histories. Individuals with cardio-metabolic health problems were then placed into one of three groups depending on whether they were currently seeking treatment for all of their conditions, some of them or none.

All subjects were followed up for a period of five years after which it was seen that those who had all of their conditions treated were 39 percent less likely to develop Alzheimer's disease, compared to those who received no treatment. Those who were treated for some of their conditions reduced their risk by 25 percent. These findings provide further evidence that taking steps to control type 2 diabetes symptoms may contribute to good overall health.

Dr. Jeffrey Burns, director of the Alzheimer and Memory Program at University of Kansas Medical Center said, “That's a terrific study. It says vascular disease has a real effect on the manifestation of Alzheimer's disease. The vascular disease is damaging your brain and is probably causing you to have lowered resistance to the pathological effects of Alzheimer's disease.” Vascular disease can damage the blood vessels leading to and within the brain, he added. “With vascular disease, the brain is under attack two ways, so you develop Alzheimer's disease sooner.”

Cholesterol-lowering medications, blood pressure medications and lifestyle changes such as losing weight and exercising can all help lower vascular disease risk factors, Dr. Steven DeKosky, vice president and dean of the University of Virginia School of Medicine said. “If you aggressively treat vascular disease factors, you can delay the breakthrough of clinical symptoms of Alzheimer's,” DeKosky said. “That's a pretty exciting finding.”