People with above-average blood sugar levels may be more likely to develop some form of dementia, new research shows.
It is believed that between five and seven million people in the UK have pre-diabetes, which puts them at higher risk of developing type 2 diabetes.
A study conducted by University College London (UCL) has now shown that people with this condition are 54% more likely to develop vascular dementia over an average of eight years.
Vascular dementia is a common type of dementia caused by decreased blood flow to the brain.
The study, published in the journal Diabetes, Obesity and Metabolism, analyzed data from 500,000 people with an average age of 58 years from the UK biobank.
It found that people with prediabetes were 42% more likely to experience cognitive decline over an average of four years.
The increased risk for brain function persisted after considering other factors such as age, withdrawal, smoking, and body mass index.
The study’s lead author, Dr. Victoria Garfield said while the results “cannot prove” that higher blood sugar levels cause brain health deterioration, the “possible link” warranted further investigation.
Dr. Garfield of the UCL Institute of Cardiovascular Science said, “Our research shows a possible link between higher blood sugar levels, a condition often referred to as ‘prediabetes,’ and a higher risk of cognitive decline and vascular dementia.
“As an observational study, it cannot be shown that higher blood sugar levels worsen brain health. However, we believe there is a possible link that needs further investigation.
“Previous research has shown a link between poor cognitive outcomes and diabetes, but our study is the first to look at how relatively high blood sugar levels, but not yet diabetes, can affect our brain health.”
The researchers looked at how different blood sugar levels or glycemic conditions were related to performance on cognitive tests over time, diagnoses of dementia, and brain structure.
Participants were tested to determine their average blood sugar level over the past two to three months and were divided into five groups based on the results.
The researchers used data from repeated visual memory assessments to determine whether participants had cognitive decline.
They found that prediabetes was linked to a higher chance of developing vascular dementia, but not Alzheimer’s disease.
Meanwhile, people with diabetes were three times more likely to develop vascular dementia than people whose blood sugar levels were considered normal and were more likely to develop Alzheimer’s disease.
People with prediabetes can reduce their risk of developing type 2 diabetes by eating a healthy and balanced diet, being more active, and maintaining a healthy weight.