Do vascular diseases deliver clues to treat Alzheimer's?

16/01/2015
Graphic: Iconic man on a seesaw between heart and brain

A mix of vascular diseases and Alzheimer's plaques could be the leading cause of dementia; ©panthermedia.net/ arkela

A growing body of research suggests that the most common cause of dementia in older people is a mix of vascular and Alzheimer's-related brain abnormalities, and that approximately half of people who die with Alzheimer's also have evidence of strokes in their brains.

Furthermore, when strokes and hallmark Alzheimer's plaques and tangles are combined, it increases a person's likelihood of experiencing dementia. Stroke, or as it is known more generally as cerebrovascular disease, occurs with aging and is made worse by conditions like smoking, hypertension or diabetes.

Recommendations by a group of scientists to bolster research on how Alzheimer's and vascular conditions progress together and influence each other are available in Alzheimer's & Dementia: The Journal of the Alzheimer's Association. The authors hope this research agenda, if executed, will uncover new clues for effectively treating or preventing dementia.

"We are encouraged by the potential for new treatment strategies for dementia to arise from studying the crossover of vascular factors with the progression of Alzheimer's," says Heather M. Snyder, Ph.D., director of medical and scientific operations for the Alzheimer's Association, and first author of the new article. "In terms of next steps, we need to develop the research tools and collaborations necessary to further scientific investigation in this promising area of study."

Cerebrovascular disease can be prevented with a variety of drug and lifestyle interventions; however, this has not yet been established for dementia. Snyder says, "Whether improved control of vascular risk factors can be translated to decreased dementia risk is not known, but results from a number of studies suggest that it is possible, and this untapped potential definitely deserves greater research attention."

In December 2013, the Alzheimer's Association, with scientific input from the National Institutes of Health's National Institute of Neurological Disorders and Stroke (NINDS) and National Heart, Lung and Blood Institute (NHLBI), convened a group of scientific experts to discuss the scientific findings to date and gaps in research on vascular contributions in Alzheimer's and related forms of dementia. The newly-published article summarizes the meeting and discussions, including an outline of next steps.

"Blood vessels that deliver nutrients to the brain and carry away waste are vital for normal cognitive function," says co-author Roderick Corriveau, Ph.D., the NINDS program director who oversees dementia research. "Understanding vascular contributions to cognitive impairment and dementia, including changes due to stroke, heart disease and diabetes, are critically important to guide the development of preventions and treatments for dementia."

"Inadequate blood flow can damage and eventually kill cells anywhere in the body," says Donna M. Wilcock, Ph.D., a neurovascular researcher who is an assistant professor in the Department of Physiology at the University of Kentucky College of Medicine in Lexington and a co-author of the paper. "Since the brain has one of the body's richest networks of blood vessels, it is especially vulnerable. Considering this and demonstrated success in reducing risk for heart disease, stroke and other vascular-related diseases through healthy lifestyle modifications and use of medications, it only makes sense to increase our understanding of the role vascular factors play in Alzheimer's and dementia."

MEDICA.de; Source: Alzheimer’s Association