Brain Lesions Predict Alzheimer's Disease: Secondary Risk Factor Revealed

Alzheimer's disease may have another contributing cause, according to researchers. A new study shows that damage to small blood vessels in the brain could be a secondary risk factor that could lead to the disease.

This damage to blood vessels is known as white matter hyperintensities and is seen as small brain lesions that are detectable on MRI.

The study, published in JAMA Neurology, looked at data from 100 older participants in a neuroimaging project called the Alzheimer's Disease Neuroimaging Initiative. Of the 100 patients, the study examined 21 who were cognitively normal, 59 with mild cognitive impairment and 20 who had been diagnosed with Alzheimer's disease. Using MRI, the researchers scanned the patients and then examined the results. In order to quantify their findings, they used PET studies with the Pittsburgh Compound B (PIB) tracer.

The researchers found that of the 41 scans from patients with Alzheimer's disease and control subjects, 68 percent were classified as PIB positive. Of this 68 percent, only 11 were defined as normal control subjects while the others had Alzheimer's  disease. Researchers noted that only three of the 13 patients without amyloidosis, which is when plaques are formed and which is viewed as the primary cause of the disease, had the criteria for the disease. They also found that beta amyloid plaques, the primary factor of this disease development, and brain lesions were independent predictors of Alzheimer's.

The findings show that these brain lesions could account for an additional risk factor when it comes to Alzheimer's disease. Altering the risk factors for white matter hyperintensities could potentially help prevent the clinical diagnosis of Alzheimer's.

That said, this particular study was small, as the researchers pointed out. In order to have more conclusive results, it would need to be conducted on a larger scale. Nonetheless, these findings could have broad implications for both the treatment and diagnosis of this disease.