Diabetes Identified as a Top Risk Factor for Dementia

Diabetes is 1 of the most important risk factors for developing dementia in middle-aged and older individuals, according to new research published in Neurology.¹

Researchers from the National University of Ireland (NUI) Galway, Boston University, and the University of Texas health Sciences Center in San Antonio examined data from 5000 people in the United States-based Framingham Heart Study, measuring risk factors for dementia, including age, sex, blood pressure, use of blood pressure lowering medication, a history of cardiovascular disease, atrial fibrillation and diabetes mellitus, NUI Galway said in a news release.² 

Risk factors were measured at age 55 and again at ages 65, 70, 75 and 80 years.

The researchers found that the most important vascular risk factors for dementia were high blood pressure, diabetes at age 55, and cardiovascular disease at age 65.

At ages 70 and 75, diabetes and previous stroke were the top risk factors,and at age 80, diabetes, previous stroke, and not taking blood-pressure lowering medication were the top risk factors.

“We found that people who had diabetes at the age of 55 were four times more likely to go on to develop dementia than people who did not have diabetes at that age,” said Emer McGrath, associateprofessor at the College of Medicine Nursing and Health Sciences at NUI Galway and consultantneurologist at Saolta University Hospitals.

In addition, people with heart disease at age 65 were nearly twice as likely to later develop dementia as those who did not have a heart condition, while people with a stroke at age 70 were over three times as likely to develop dementia compared to those with no stroke, McGrath noted.

Accurately predicting a person’s future risk of dementia could inform personalized approaches to risk factor and lifestyle modification to help reduce that risk, according to McGrath. "However, predicting this is challenging as the relationship between dementia and vascular risk factors such as diabetes, blood pressure, heart disease and stroke varies with age.”

“Our study shows that predicting a person’s risk of dementia needs to be very much tailored towards the individual, taking into account their age, sex, vascular risk factors and evidence of organ damage, such as previous heart attack or stroke,” McGrath added.

The research has “important implications for dementia prevention at a population-level,” according to McGrath. “Controlling vascular risk factors such as high blood pressure and diabetes mellitus, adopting healthier eating habits and following an active lifestyle, particularly at the early to mid-life stage, could significantly reduce a person’s risk of developing dementia down the line.”

An estimated 64,000 people are living with dementia in Ireland, according to the Alzheimer’s Association of Ireland, The number of people with the condition will more than double in the next 25 years to more than 150,000 by 2045, according NUI Galway.

“Diabetes has been identified as 1 of 7risk factors responsible for up to one-third of cases of Alzheimer’s disease dementia and represents an important modifiable target for dementia prevention at a population-level,” said Professor Sudha Seshadri, co-author of the study, professor of neurology and director of the Glenn Biggs Institute for Alzheimer’s & Neurodegenerative Diseases at the University of Texas Health Sciences Center, San Antonio, and senior investigator with the Framingham Heart Study. 

References

1. McGrath ER, Beiser AS, O’Donnell A, et al. Determining vascular risk factors for dementia and dementia risk prediction across mid- to later-life: The Framingham Heart Study.Neurology. Published online May 18, 2022. Doi:10.1212/WNL.0000000000200521

2. International study identifies most important vascular risk factors for dementia. News release. National Unviersity of Ireland Galway. May 19, 2022. Accessed May 24, 2022. https://www.eurekalert.org/news-releases/953299