A study examined brain tissue from 230 individuals diagnosed with Parkinson’s disease and discovered that women exhibited substantially higher levels of Alzheimer’s-related amyloid plaques than men. The research involved samples from 74 women and 156 men who took part in the Arizona Study of Aging and Neurodegenerative Disorders, with their cognitive function monitored during life and their brains analyzed after death.
The results revealed a distinct gender-based difference in brain pathology. On average, women scored 6.5 out of 15 on amyloid plaque measurements, whereas men averaged 4.9. Over half of the women (56.8%) displayed raised amyloid levels, compared to 39.7% of men. Even after accounting for age, genetic risk factors such as the APOE ε4 gene, and Lewy body levels, women faced more than double the likelihood of showing significant amyloid buildup.
This trend did not apply uniformly to all Alzheimer’s-related markers. Tau tangles, another indicator of Alzheimer’s, showed no meaningful variation between men and women. The disparity in amyloid accumulation was most noticeable in those with Parkinson’s disease dementia rather than mild cognitive impairment or normal cognitive function.
Although women showed greater amyloid accumulation, the study did not detect a corresponding rise in dementia diagnoses. In fact, women outperformed men on verbal learning tests, indicating potential cognitive resilience. The research does not confirm whether women face a higher Alzheimer’s risk—it simply documents existing brain pathology after death.
Parkinson’s and Alzheimer’s share overlapping brain changes, but this investigation suggests possible gender-specific variations. While women with Parkinson’s exhibited more amyloid plaques, their dementia rates aligned with those of men. The factors behind this resilience remain unexplained, and the study’s limited sample size prevents broad generalizations.
Despite this difference, dementia rates between genders remained similar, and women performed better on verbal learning tests.