White Matter Hyperintensities Tied to Alzheimer's Disease
(HealthDay News) – The presence of Pittsburgh Compound B (PIB) positron-emission tomography-derived amyloids and increased total white matter hyperintensities (WMHs) are independently associated with Alzheimer's disease (AD) diagnosis, according to a study published online Feb. 18 in JAMA Neurology.
Frank A. Provenzano, from Columbia University in New York City, and colleagues used the Alzheimer's Disease Neuroimaging Initiative database to identify baseline PIB positron-emission tomography values. Accompanying structural magnetic resonance imaging data were used to calculate total WMH volume in 20 AD patients and 21 controls. Further analysis was conducted on 28 PIB-positive participants and 59 participants with mild cognitive impairment.
The researchers found that PIB positivity and increased total WMH volume independently predicted AD diagnosis. PIB-positive subjects diagnosed with AD had greater WMH volume than normal control subjects. WMH and PIB status at baseline conferred risk for future diagnosis of AD among subjects with mild cognitive impairment.
"White matter hyperintensities contribute to the presentation of AD and, in the context of significant amyloid deposition, may provide a second hit necessary for the clinical manifestation of the disease," the authors write. "As risk factors for the development of WMHs are modifiable, these findings suggest intervention and prevention strategies for the clinical syndrome of AD."
The Alzheimer's Disease Neuroimaging Initiative receives funding from numerous pharmaceutical companies.