MRI shows brain atrophy pattern that is predictive of Alzheimer’s

Using special MRI methods, researchers have identified a pattern of regional brain atrophy in patients with mild cognitive impairment (MCI) that indicates a greater likelihood of progression to Alzheimer’s disease. The findings are published in the online edition of Radiology. The study’s lead author, Linda K. McEvoy, Ph.D., assistant project scientist in the Department of Radiology at the University of California San Diego School of Medicine in La Jolla, USA said that previously this pattern had been observed only after a diagnosis of probable Alzheimer’s disease. The current results show that some individuals with MCI have the atrophy pattern characteristic of mild Alzheimer’s disease, and these people are at higher risk of experiencing a faster rate of brain degeneration and a faster decline to dementia than individuals with MCI who do not show that atrophy pattern.
For the study, Dr McEvoy and colleagues set out to determine if they could identify a pattern of regional atrophy characteristic of mild Alzheimer’s disease in order to aid in the prediction of cognitive decline in patients with MCI. The researchers analysed brain MR images from 84 patients with mild Alzheimer’s disease, 175 patients with MCI and 139 healthy controls, using semi-automated, individually specific quantitative MRI methods. The results showed widespread cortical atrophy in some patients with MCI, involving all cortical areas except those involved with processing of primary motor and sensory information. However, most indicative of future cognitive decline were atrophy in parts of the medial and lateral temporal lobes and in the frontal lobes. This pattern was also present in the patients with mild Alzheimer’s disease. Although these individuals were reporting problems mainly with memory, the atrophy involved more than just memory areas, extending into brain regions involved in planning, organisation, problem solving and language. Follow-up data were available for 160 patients with MCI. The patients exhibiting atrophy in the brain regions described above showed significant one-year clinical decline and structural brain loss and were more likely to progress to a probable diagnosis of Alzheimer’s disease. MCI patients without that pattern of atrophy remained stable after a year.
Dr McEvoy hopes that these findings will have an impact on the design of clinical trials to test medications that may slow or halt the progression of Alzheimer’s disease.