Elevated blood glucose levels affect the human brain. Therefore, a person with diabetes is at greater risk of developing some form of dementia in the future, which includes disorders that affect memory, thinking and social skills.
A new study was led by researchers at the Johns Hopkins Bloomberg School of Public Health along with collaborators from other US universities and focused on the link between glucose levels and mental health.
They discovered at what ages diabetes is associated with an increased risk of dementia.
The finding was published in Diabetologia, the journal of the European Association for the Study of Diabetes, and its results suggest that the general population and the medical community should pay more attention to everything that can be done to prevent diabetes. .
“The results of our study suggest that if we can prevent people with prediabetes from progressing to diabetes, we might help prevent dementia later in life,” said epidemiologist Elizabeth Selvin, the lead researcher at the University of Johns Hopkins.
Before the study, it was already known that 70% of people with so-called “prediabetes” will develop the disease diabetes throughout their lives.
Prediabetes is the condition in which the blood sugar level is high, but not high enough to be diagnosed as type 2 diabetes.
Being overweight or obese, a sedentary lifestyle, a family history, and being a tobacco user are risk factors for both prediabetes and diabetes.
“The buildup of two proteins, called amyloid beta and tau, can cause brain cell loss, which in turn can lead to dementia, said Dr. Selvin.
Prediabetes is “a condition that puts people at high risk for diabetes.
It is not clear if prediabetes itself is a risk factor for dementia or if people with prediabetes are simply at increased risk for diabetes, which is a risk factor for dementia.”
The researchers analyzed data from participants in the Atherosclerosis Risk in Communities (ARIC) study, which is sponsored by the US National Heart, Lung, and Blood Institute.
Participants were between the ages of 45 and 64 in 1987-1989 and came from four US counties: Forsyth County, North Carolina; Jackson, Mississippi; suburbs of Minneapolis, Minnesota; and Washington County, Maryland.
The reference period for the analysis was study visit 2 (1990-1992), which was the first time glycosylated hemoglobin, a measure of glycemic control, and cognitive function were measured in the study.
Assessments of cognitive function incorporated data from a scoring system that included three cognitive tests, administered at Visits 2 (1990-1992) and 4 (1996-1998), the expanded neuropsychological collection of ten tests, administered from the Visit 5 (2011-2013) and the interview with informants.
They also underwent the Mini Mental State Test.
Participants were followed up until 2019.
They assessed the relationship between prediabetes and dementia risk before and after accounting for the subsequent development of type 2 diabetes among participants with prediabetes at baseline.
This was done to understand how much of the association of prediabetes with dementia was explained by progression to diabetes.
They also tested whether age at diabetes diagnosis modified dementia risk.
Among the 11,656 participants without diabetes at baseline, 20% (2,330) had prediabetes.
They found that the earliest age of progression to type 2 diabetes had the strongest association with dementia.
This means that people who develop diabetes before the age of 60 have a three times higher risk of developing dementia.