AsianScientist (Dec. 5, 2013) – Studies on Alzheimer’s disease and other forms of dementia have long focused on what is taking place inside the brain. Now an international research team studying Alzheimer’s and mild cognitive impairment has reported potentially significant findings on a vascular abnormality outside the brain.
The study, published in the Journal of Alzheimer’s Disease, included researchers from the University at Buffalo in the US, the University of Bradford in the UK and National Yang-Ming University School of Medicine in Taiwan.
The researchers studied a hemodynamic abnormality in the internal jugular veins called jugular venous reflux or JVR. It occurs when the pressure gradient reverses the direction of blood flow in the veins, causing blood to leak backwards into the brain. JVR occurs in certain physiological situations, if the internal jugular vein valves do not open and close properly, which occurs more frequently in the elderly. This reverse flow is also believed to impair cerebral venous drainage.
Results from the study showed that JVR is associated with a higher frequency of white matter changes in patients with mild cognitive impairment and Alzheimer’s disease.
“We are the first to observe that JVR may be associated with formation of these lesions in the brain, given the fact that Alzheimer’s patients have more white matter lesions than healthy people,” said Ching-Ping Chung, the first author on the study and assistant professor of neurology at National Yang-Ming University.
The brain’s white matter is made of myelin and axons that enable communication between nerve cells. White matter changes have been found to have a direct relationship to the buildup of amyloid plaque long seen as central to the development of Alzheimer’s disease.
In addition, the study found that JVR appeared to be associated with dirty-appearing white matter, which is thought to represent early stage lesion formation.
The research involved 12 patients with Alzheimer’s disease, 24 with mild cognitive impairment and 17 age-matched elderly controls. Participants underwent Doppler ultrasound exams and magnetic resonance imaging scans.
But the authors caution that the study is small and that the results must be validated in larger, future studies. They say that the finding has potential implications for a better understanding of Alzheimer’s and other neurological disorders associated with aging.
The article can be found at: Chung I et al. (2013) Jugular Venous Reflux and White Matter Abnormalities in Alzheimer’s Disease: A Pilot Study.
Source: National Yang-Ming University; Photo: IsaacMao/Flickr/CC.
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