Poorer cardiovascular health in childhood and adolescence may be linked to early differences in brain structure, particularly in areas of the brain known to be affected in dementia in later life, according to a new study co-led by a UCL researcher.
Obesity, hypertension (high blood pressure) and physical inactivity are known to be cardiovascular risk factors for dementia in middle age but, so far, little is known about the links between heart and brain health much earlier in life.
Researchers looked at data from more than 860 children and young people between the ages of seven and 17, including brain scans, levels of physical activity, blood pressure and body mass index (BMI).
The new paper, published in the journal eBioMedicine, found a link between increased BMI, higher blood pressure, and lower physical activity in adolescence and subsequent brain structure in young adulthood - a period when the body undergoes significant change.
The links were particularly evident in brain regions that are known to be affected in dementia in old age, suggesting that lifestyle changes early in childhood may set the stage for later decline in brain health.
Senior author Dr Scott Chiesa (UCL Institute of Cardiovascular Science) said: "Current evidence suggests that up to 45% of dementia cases could be delayed or reduced by limiting exposure to common lifestyle-related risk factors such as obesity, physical inactivity, and high blood pressure. While considerable research has focused on understanding how these risk factors may impact brain structure and function in later life, very little attention to date has been paid to the effect they may potentially have during the earlier developmental stages of life."
Holly Haines, lead author on the paper from the University of Oxford, said: "Our research shows that cardiovascular health in the earliest stages of life may already be important for the structure of brain regions known to be affected in dementia in old age - much earlier than previously thought."
The scientists found that markers of poorer cardiovascular health (such as higher childhood blood pressure and faster growth of BMI across adolescence) were associated with differences in the structure of a type of brain tissue called grey matter - including its thickness and surface area. These findings were predominantly in brain areas which are known to be involved in thinking and memory. Similar links between heart health and brain health have already been shown in older patients with memory difficulties and dementia.
They say the research could help pave the way in identifying and mitigating dementia risks earlier in life, but that further research is needed with a more diverse group of participants to be able to generalise the findings to the wider population.
