Anne Cross, MD, Professor of Neurology at Washington University in St. Louis, has treated patients with MS for decades. She noticed that while her patients were living long enough to be at risk for AD or had a family history of neurodegenerative disease, they tended not to develop the condition. To understand why this may be the case, Cross decided to compare levels of amyloid beta in patients with MS and controls matched for age, genetic risk for AD, and cognitive decline.
To do so, Cross and her team recruited 100 patients with MS and 300 matched controls. All patients underwent a new, FDA-approved blood test known as PrecivityAD2 to predict the presence of amyloid plaques in their brains. Eleven of the MS patients also underwent PET scans.
Ultimately, the researchers found that around 50% fewer MS patients had amyloid pathology than their matched peers. They additionally found that the more typical patients’ MS history in terms of age of onset, severity, and overall progression, the less likely they were to have amyloid plaque accumulation in their brains.
To explain the findings, the researchers noted that periodic inflammatory flare-ups that attack the central nervous system in MS may also reduce amyloid plaques. Previous research shows, for example, that activated microglia, which are part of the brain’s immune response to MS, clear amyloid from the brain in animal models.
The researchers now aim to conduct further research to understand which human genetics are involved, and to test amyloid plaque development in animal models representing MS.
Sources: Science Daily, Annals of Neurology