Midlife Vascular Risk Factors Drive Dementia Later in Life

Megan Brooks

February 24, 2017

HOUSTON, Texas — A new study provides more evidence that vascular risk factors in midlife are associated with increased risk for dementia later in life.

Smoking, hypertension, and diabetes in midlife were all associated with increased risk for dementia. Midlife diabetes raises the risk almost as much as does carrying the APOE ε4 allele, the most important known genetic risk factor for Alzheimer's disease.

"The health of your vascular system in midlife is really important to the health of your brain when you are older," Rebecca F. Gottesman, MD, PhD, lead researcher and associate professor of neurology and epidemiology at the Johns Hopkins University in Baltimore, Maryland, said in a statement.

Dr Rebecca F. Gottesman

"We need to better understand whether treatment [of vascular risk factors] really makes a difference in reducing Alzheimer's. Certainly, we don't have other ways right now to reduce Alzheimer's, but we know how to treat and prevent vascular disease," Dr Gottesman said.

She presented the results from the ongoing Atherosclerosis Risk in Communities (ARIC) study during a media briefing here at the International Stroke Conference (ISC) 2017.

Participants in the biracial ARIC study were recruited from four US communities in the late 1980s when they were 45 to 64 years old. Vascular risk factors were assessed at baseline and patients were followed at regular intervals for about 25 years.

Among 15,744 participants in the cohort, 1516 cases of dementia were identified at the 2011–2013 assessment.

As expected, the risk for dementia increased with age, Dr Gottesman reported. In the overall cohort, black participants had a higher risk for dementia. Midlife risk factors for later-life dementia included being a smoker; having diabetes, hypertension, or prehypertension; carrying the APOE ε4 allele; and not graduating from high school.

Table. Risk for Later-Life Dementia by Midlife Factors

Risk Factor Hazard Ratio for Dementia (95% Confidence Interval)
Black race 1.3 (1.17 - 1.50)
Less than high school education 1.4 (1.22 - 1.60)
Smoker 1.4 (1.19 - 1.58)
APOE ε4 allele 2.0 (1.76 - 2.19)
Diabetes 1.8 (1.54 - 2.08)
Prehypertension 1.4 (1.17 - 1.57)
Hypertension 1.4 (1.24 - 1.63)


"We also looked at differences by race and found that some risk factors have a slightly different effect in blacks vs whites," said Dr Gottesman.

"Smoking was only a risk factor for dementia in white participants. And the APOE allele had a stronger effect in whites than in blacks. However, the risk of the individual risk factors didn't really differ by race; diabetes was an important risk factor in both blacks and whites, as was hypertension."

Making a Healthy Transition

Karen Furie, MD, American Stroke Association spokesperson and neurologist-in-chief, Rhode Island Hospital, The Miriam Hospital and Bradley Hospital in Providence, commented on the study for Medscape Medical News.

"When people think about healthy aging, and the way that they would like to transition from middle to later life, it's very important that people be able to retain their cognitive abilities and maintain their usual quality of life in terms of being able to work and drive and care for themselves," she said. "And losing independence, particularly because of memory problems, is one of the things that really terrify people as they get older."

This study is "important," said Dr Furie, "because it identifies factors that are modifiable, that are easy to identify in midlife, that contribute to cognitive dysfunction in the elderly. And so, it really empowers people to change their lifestyle habits and get treatment for their medical conditions, so that they can age successfully and retain independence and high quality of life in later decades."

The study was funded by the National Heart, Lung, and Blood Institute and the National Institute of Neurological Disorders and Stroke. Dr Gottesman is associate editor of the journal Neurology.

International Stroke Conference (ISC) 2017. Abstract 98. Presented February 22, 2017.

For more Medscape Neurology news, join us on Facebook and Twitter


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.