Brain volume loss, or brain atrophy, happens when the brain shrinks over time due to the death of nerve cells and their connections. Several factors speed up this process, making it worse in certain people or conditions.
In multiple sclerosis, or MS, the immune system attacks the protective covering around nerve cells, leading to faster brain shrinkage. This loss ties directly to worse disability over time. Treatments called disease-modifying therapies, or DMTs, like Ponvory and Kesimpta, slow this atrophy and help delay symptoms. Studies show that drugs cutting brain volume loss by even a little also reduce disability buildup, with Kesimpta standing out by cutting it by 52 percent.[1]
Low cardiorespiratory fitness plays a big role too, especially in people with coronary artery disease, or CAD. Cardiorespiratory fitness means how well your heart and lungs supply oxygen during exercise. Those with low fitness levels have smaller brain volumes, particularly in the hippocampus, a key area for memory. Higher fitness links to larger brain regions and a younger-looking brain overall. Even simple exercise tests show this connection, suggesting better fitness might protect against shrinkage in at-risk groups.[2]
Aging affects men and women differently. Research finds men’s brains lose volume faster and in more areas than women’s as they get older. This quicker decline might make men more prone to brain changes, though women face higher dementia risk from other factors like gene-driven inflammation after menopause.[3]
Stroke in certain brain arteries can also trigger rapid atrophy. Tools that measure shrinkage from standard MRI scans predict worse outcomes after these events, showing how acute damage accelerates loss.[4]
Sources
https://multiplesclerosisnewstoday.com/news-posts/2025/12/12/dmts-protect-brain-volume-slow-disability-progression/
https://academic.oup.com/eurjpc/advance-article/doi/10.1093/eurjpc/zwaf765/8380283
https://www.sciencefocus.com/news/women-brain-age-men-dementia-alzheimers
https://pmc.ncbi.nlm.nih.gov/articles/PMC12756492/
