A recent study by researchers at Oxford Population Health has revealed a significant link between poor metabolic health and a decline in memory, cognitive abilities, and overall brain health. Published in Diabetes Care, this study is the largest of its kind, exploring the relationship between metabolic and brain health in a comprehensive analysis of nearly 40,000 participants.
UNDERSTANDING METABOLIC SYNDROME
Metabolic syndrome, also known as poor metabolic health, is diagnosed when an individual has at least three of the following conditions:
- Large waist circumference
- High triglycerides
- High blood pressure
- High blood sugar
- Low levels of high-density lipoprotein (HDL) cholesterol, often referred to as “good” cholesterol
Globally, one in four adults is affected by metabolic syndrome. Previous research has suggested a connection between poor metabolic health and an increased risk of dementia. However, this new study expands on these findings, indicating that metabolic syndrome can negatively impact brain health even in those who do not have dementia.
STUDY OVERVIEW
The study utilized data from the UK Biobank, which includes over half a million participants aged 40-69 years who enrolled between 2006 and 2010. More than 50,000 of these participants underwent brain imaging and cognitive testing from 2014 onwards. Researchers focused on 37,395 participants who did not have dementia, of whom 7,945 had poor metabolic health at the start of the study.
KEY FINDINGS
The study found that individuals with poor metabolic health exhibited several concerning brain health indicators:
- Reduced Brain Volume: Participants with metabolic syndrome had lower total brain volume and reduced grey matter volume. Grey matter is crucial for processing information in the brain.
- Increased White Matter Hyperintensities: These are markers of vascular brain damage, previously linked to dementia.
- #Memory Problems: Reduced hippocampal volume and poor performance in cognitive tests of working memory and verbal declarative memory were noted.
- Cognitive Decline: Participants showed worse performance in tests measuring processing speed, verbal and numerical reasoning, nonverbal reasoning, and executive function.
IMPLICATIONS FOR BRAIN HEALTH
Danial Qureshi, a PhD candidate at Oxford Population Health and lead author of the study, emphasized the significance of the findings. “Our study shows that poor metabolic health is associated with a reduction in brain volume and worse cognitive performance, potentially contributing to the future development of dementia. Up to 40% of dementia cases may be preventable through dietary and lifestyle changes. Therefore, maintaining metabolic health is crucial for reducing the risk of dementia and related brain disorders,” Qureshi said.
Dr. Thomas Littlejohns, Senior Epidemiologist at Oxford Population Health and senior author of the study, added, “Our findings highlight that poorer metabolic health is linked to worse brain health even in individuals without dementia. This association was consistent across different age groups. The next step is to confirm if better prevention, treatment, and management of metabolic conditions lead to improved brain health in both mid and later life.”
EXPERT OPINIONS
Madeleine Walpert, Research Fellow at Dementia UK, commented on the study’s broader implications. “This large study underscores the importance of recognizing conditions that increase dementia risk and exhibit similar symptoms. The findings show that metabolic syndrome reduces grey matter volume, increases vascular brain damage, and affects cognition across various domains. This parallels some hallmark symptoms of dementia.”
Walpert emphasized the necessity of a holistic approach to treating and caring for individuals with coexisting health conditions. “Addressing not just individual conditions but also their interplay and combined impact on overall health and wellbeing is crucial, especially since 9 in 10 people with dementia also have another long-term health condition,” she added.
The study by Oxford Population Health sheds light on the critical relationship between metabolic health and brain function. With poor metabolic health linked to significant declines in brain volume, cognitive abilities, and overall brain health, maintaining metabolic health emerges as a vital component of preventing dementia and promoting healthy aging. As researchers continue to explore these connections, it becomes increasingly clear that addressing metabolic syndrome can have far-reaching benefits for brain health and cognitive function.