New research from the University of Bristol indicates a significant association between high Body Mass Index (BMI) and an increased risk of vascular dementia, a condition affecting millions globally. This study utilized a method called Mendelian Randomisation, which examines genetic influences on health outcomes, to analyze population data from the UK and other regions.
The findings reaffirm existing knowledge that a higher BMI correlates with a greater risk of vascular-related dementia. Notably, the researchers identified high blood pressure as a major contributing factor to this relationship, suggesting that effective treatment for hypertension could substantially reduce the risk of cognitive decline. According to Dr. Liv Tybjærg Nordestgaard, the first author of the study, “Dementia is a devastating disease that currently affects 50 million individuals worldwide. Unfortunately, treatment and prevention options are scarce. Our study highlights the potential for reducing vascular-related dementia risk by addressing high BMI and/or high blood pressure in the population.”
Vascular dementia is characterized by a decline in cognitive function due to reduced blood flow to the brain and is estimated to affect around 180,000 people in the UK, as reported by the NHS. The symptoms of this condition typically worsen over time, though there are some strategies to slow its progression.
Implications for Prevention and Treatment
This research is part of a broader trend in studies indicating that lifestyle changes could prevent or delay dementia cases. Notably, the 2024 Lancet Commission suggested that almost 45% of dementia cases might be preventable by addressing key risk factors. These factors include not only high BMI and hypertension but also high LDL cholesterol, diabetes, smoking, excessive alcohol consumption, and obesity.
Dr. Wendy Weidner, Director of Research and Publications at Alzheimer’s Disease International, emphasized the importance of early intervention. “This study underscores the critical importance of a life-course approach to risk reduction, with targeted interventions across different stages of life. By identifying and addressing these risk factors early on, especially in lower-resourced settings, we have a profound opportunity to reduce the global impact of dementia. While we have yet to find a cure for dementia, every proactive step in addressing dementia risk can make a world of difference at a personal and societal level, and policymakers have an essential role to play,” she stated.
Understanding BMI and Its Limitations
BMI is a widely used metric that calculates healthy body weight based on height and weight. While it serves as a useful starting point for assessing health, it has limitations. Factors such as muscle mass, bone density, age, sex, and ethnicity can all impact BMI readings. The NHS indicates that a higher BMI increases the likelihood of developing long-term health conditions, including type 2 diabetes and heart disease.
It’s important to note that BMI alone does not differentiate between muscle and fat. For example, an individual with high muscle mass may be classified as overweight or obese despite having low body fat. Therefore, measuring waist circumference may provide a clearer picture of overall health.
In summary, the research conducted by the University of Bristol highlights a critical health issue with global implications. By understanding and addressing the links between BMI, hypertension, and vascular dementia, there is potential for significant advancements in prevention and treatment strategies.
