Lifestyle choices could affect brain's 'brake system' and put people at higher risk of dementia’

Forty-five percent of dementia cases are potentially preventable, and simple lifestyle choices including exercise, diet and social connection all contribute to your risk score.  

But what if these risk factors were leaving chemical warning signs of decline in your brain – long before any symptoms of dementia played out?  

Researchers from the University of the Sunshine Coast’s Thompson Institute believe they’ve found just that.   

It not only opens new avenues for early detection in dementia research – it could also help our understanding of how the brain deteriorates to increase risk of earlier dementia.  

The study, published today in Cerebral Cortex, used Magnetic Resonance Imaging and MR-spectroscopy to measure the brain chemical levels of 79 healthy older adults.  

All participants had normal memory, thinking skills and cognitive function. What varied was their modifiable-dementia risk score – calculated from health and lifestyle factors such as physical activity, sleep, social engagement, and diet.   

Lead author Dr Jacob Levenstein said the research team discovered specific patterns in individuals’ brain chemistry relating to that risk score.  

“We examined the concentration levels of Gamma-aminobutyric acid (GABA) – which you can think of as the brain’s ‘brake system,” he said.  

“GABA is a neurochemical messenger that helps calm down brain activity and keep neural networks balanced. These results suggest ‘riskier’ lifestyle choices could hinder the brain’s ability to properly regulate itself.  

"We found that with higher modifiable dementia risk scores, individuals had lower GABA concentrations in movement and sensory brain regions.     

“In the prefrontal cortex – a brain region that handles complex thinking and decision-making – we also found that with higher modifiable dementia risk, individuals had lower concentrations of total N-acetylaspartate (tNAA) and total choline (tCho).  

“These two neurochemicals play important roles in brain tissue health and cell-to-cell communication.  

“Lower levels of these neurochemicals in the brain's ‘command centre’ may suggest deterioration occurs long before noticeable changes in behaviour or memory.”  

The findings not only open the door for new early detection and intervention research, they also shed light on how the brain might deteriorate before dementia sets in.  

“Crucially, these three neurochemical markers were identified in healthy older adults, meaning they could play a role in the detection of dementia years before behavioural symptoms appear, giving a head-start on prevention and mitigation” Dr Levenstein said.  

As co-author of the research and Lead of the Thompson Institute’s Healthy Brain Ageing Program Dr Sophie Andrews points out, there is additional good news in these findings too.  

“These are modifiable factors. You can make simple everyday choices that will improve your brain’s health trajectory,” she said.  

“We’ve shown that simple things like improving physical activity levels and sleep quality, looking after your mental health, and moving toward a Mediterranean-style diet, can significantly improve your outlook.”   
 
The research team included Thompson Institute Postdoctoral Research Fellow on Trauma and Ageing Dr Ciara Treacy, who also co-authored the study.