Pesticides exposure linked to Alzheimer's disease

A new study has revealed that patients with Alzheimer's disease have significantly higher levels of DDE, the long-lasting metabolite of the pesticide DDT, in their blood than healthy people.

In a case-control study involving 86 Alzheimer's patients and 79 healthy elderly controls, researchers found that DDE levels were almost four times higher in serum samples from Alzheimer's patients than in controls.

Having DDE levels in the highest third of the range in the study increased someone's risk of Alzheimer's by a factor of four.

"This is one of the first studies identifying a strong environmental risk factor for Alzheimer's disease. The magnitude of the effect is strikingly large -- it is comparable in size to the most common genetic risk factor for late-onset Alzheimer's," co-author Allan Levey, MD, PhD, director of Emory's Alzheimer's Disease Research Center and chair of neurology at Emory University School of Medicine, said.

The study was published in JAMA Neurology.