Can neuritic plaques and neurofibrillary tangles occur in healthy older adults?

Yes, it is accurate to state that neuritic plaques and neurofibrillary tangles can be found in the brains of healthy elderly individuals, though typically in smaller amounts than those observed in patients with Alzheimer disease.1

While these structures are hallmark indicators used to diagnose Alzheimer disease during an autopsy, their presence in healthy aging complicates the understanding of their role in the disease process. It remains unclear whether these plaques and tangles are a primary cause of the condition or a consequence of it.1

Neuritic plaques consist of deteriorating neuronal material surrounding deposits of amyloid beta, while neurofibrillary tangles are composed of twisted fibers of the protein tau located within neurons. Research suggests that in healthy individuals, these features may not reach the threshold or distribution necessary to cause the cognitive decline associated with Alzheimer disease.12