Men's brains 'shrink' faster than women's

MRI data show that male brains lose volume more rapidly and more extensively as they age, but this does not explain why women still develop Alzheimer's more often.

Analysis of more than 12,000 MRI images shows that male brains shrink faster - Photo: neurorelay.com

A long-term study published in the Proceedings of the National Academy of Sciences found that men’s brains lose volume faster and more extensively as they age than women’s. However, this difference does not explain why women develop Alzheimer’s disease twice as often as men.

The study analyzed more than 12,500 magnetic resonance imaging (MRI) scans from 4,726 healthy people, each scanned at least twice, an average of three years apart. Scientists compared the thickness of the brain's gray cortex and the size of memory-related regions, such as the hippocampus.

The results showed that men lost volume in more regions, such as the postcentral cortex - which processes the sense of touch, pain and temperature - which decreased by 2% per year in men, while in women it only decreased by 1.2%.

According to Fiona Kumfor, a neuropsychologist at the University of Sydney, this result shows that the male brain ages faster, consistent with the fact that they have a shorter life expectancy.

However, if brain atrophy were the main cause of Alzheimer's, women should have had greater decline in memory-related regions, which the study did not find.

Co-author Anne Ravndal of the University of Oslo said the higher rates of Alzheimer's in women may stem from differences in lifespan or susceptibility to the disease, rather than brain structure. Experts say Alzheimer's is a complex disorder that cannot be explained by changes in brain volume with age alone.

The researchers also noted that the majority of participants had a high level of education – a factor that reduces the risk of Alzheimer’s – so the results may not fully reflect the general population. When adjusted for education and life expectancy, the rate of brain shrinkage between the sexes was nearly identical.

“Just looking at age-related brain shrinkage is not enough to understand a complex disease like Alzheimer’s,” Kumfor said. “We need more long-term follow-up studies in patients themselves to better understand how the disease progresses over time.”

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VNA

Source: https://tuoitre.vn/nao-dan-ong-teo-nhanh-hon-phu-nu-20251014141453838.htm