Researchers at Lund University tracked almost 500 participants with an average age of 65 who showed no cognitive impairment at the start of the study. Over four years, they measured changes in brain white matter, which is often damaged in vascular dementia, and monitored levels of amyloid beta and tau proteins associated with Alzheimer's disease.
The study found that most modifiable risk factors examined — including smoking, cardiovascular disease, high blood lipids and high blood pressure — were linked to damage to the brain's blood vessels and a faster accumulation of white matter changes. This vascular damage impairs blood vessel function and can ultimately lead to vascular dementia.
Diabetes was associated with increased accumulation of amyloid beta, while lower body mass index was linked to faster tau accumulation, though the researchers said these findings need further investigation and validation.
The results suggest that addressing vascular and metabolic risk factors may help delay dementia symptoms by reducing several harmful brain changes at once. Many people with dementia have multiple disease processes occurring simultaneously, including both vascular damage and Alzheimer's-related changes.
Sebastian Palmqvist, senior lecturer in neurology at Lund University, said improving vascular and metabolic health remains valuable even for people at risk of Alzheimer's disease because it can reduce the combined effects of several brain changes that occur together.
The study was published in The Journal of Prevention of Alzheimer's Disease and builds on earlier research that often did not distinguish between different underlying causes of dementia.
Lead author Isabelle Glans, a doctoral student at Lund University, noted that much existing research on modifiable risk factors does not account for the different causes of dementia, limiting knowledge of how individual factors affect specific disease mechanisms in the brain.
The findings reinforce the potential for healthier lifestyle choices to delay dementia onset by targeting multiple pathways of brain damage simultaneously.
Nearly half of dementia cases may be linked to risks you can change
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