Alzheimer's Progression Accelerates in Women with Parkinson's Protein

Mayo Clinic Study Reveals Sex-Specific Vulnerability

A Mayo Clinic study published in JAMA Network Open indicates that Alzheimer's-related brain changes progressed up to 20 times faster in women who also exhibited abnormal levels of a Parkinson's-related protein, a pattern not observed in men.

This suggests that the accumulation of alpha-synuclein, a protein linked to Parkinson's disease, alongside Alzheimer's pathology, may accelerate disease progression in women.

This interaction could help explain why women comprise nearly two-thirds of individuals living with Alzheimer's disease in the U.S. Dr. Kejal Kantarci, a Mayo Clinic neuroradiologist and senior author, stated that recognizing these sex-specific differences could inform more targeted clinical trials and personalized treatment strategies.

Understanding the Proteins Involved

Alzheimer's disease is characterized by tau protein buildup. Many individuals on the Alzheimer's spectrum also develop abnormal alpha-synuclein clumps, which are associated with Lewy body diseases like Parkinson's.

Both tau and alpha-synuclein are natural brain proteins. They can misfold and form pathological deposits in neurodegenerative diseases, disrupting brain cell communication and contributing to cognitive decline.

The Research Approach

Researchers investigated if coexisting abnormal protein buildups alter disease progression and if this effect differs between sexes.

They analyzed data from 415 participants in the Alzheimer's Disease Neuroimaging Initiative. The study used cerebrospinal fluid tests for abnormal alpha-synuclein and repeated brain imaging for tau accumulation. Approximately 17% of participants showed abnormal alpha-synuclein.

Significant Sex-Specific Findings

The study found that among participants with both Alzheimer's-related pathology and alpha-synuclein abnormalities, women accumulated tau significantly faster than men with the same coexisting protein changes.

This finding opens new avenues for understanding the disproportionate burden of dementia in women, potentially revealing new therapeutic targets.
— Dr. Elijah Mak, First Author

Future Directions

Further research will examine if these sex-specific effects also manifest in patients with dementia with Lewy bodies, where alpha-synuclein is the primary disease driver. This will help determine if the observed difference is specific to Alzheimer's disease or indicative of a broader sex-specific vulnerability across neurodegenerative conditions.