NEW YORK CITY — NYU Langone Health researchers found that maintaining normal blood pressure, no diabetes, and not smoking in midlife is associated with nearly 13 additional dementia-free years in a U.S. cohort study. The findings were published online August 5 in Neurology Open Access.

The analysis drew on data from 12,409 participants in the prospective Atherosclerosis Risk in Communities (ARIC) study. Individuals who met the criteria of normal blood pressure, no diabetes, and not smoking at age 55 lived an average of 30.1 more years dementia-free. Participants who smoked, had hypertension, and had diabetes at age 55 had a dementia-free survival of 17.5 years.

Better vascular health was linked with longer dementia-free survival in a dose-response pattern. People with all three risk factors had a higher incidence of dementia compared with those who had no risk factors. These individuals also had a higher incidence of dying before a dementia diagnosis compared with those who had no risk factors.

The ARIC study started in 1986 to evaluate midlife vascular risk factors and late-life dementia. Participants had a mean baseline age of 56 and 56% were women. Dementia was tracked through cognitive assessments, informant interviews, and continuous surveillance.

Deaths without dementia were captured from multiple sources including the National Death Index. Over a median follow-up of 26.3 years, 3,008 cases of dementia and 5,238 deaths without dementia were documented.

Hypertension was defined as systolic blood pressure ≥130 mm Hg, diastolic blood pressure ≥80 mm Hg, or the use of blood pressure medication. Diabetes was defined as fasting glucose ≥126 mg/dL, non-fasting glucose ≥200 mg/dL, a physician's diagnosis, or the use of any diabetes medication. Current smoking was self-reported.

Women lived longer without dementia than men at all risk levels. Women with all three risk factors lived an average of 18.1 years from the start of tracking without developing dementia. White participants had more years free of dementia than Black participants.

White participants with all three risk factors lived an average of 19.6 years without developing dementia. APOE4 carriers had shorter dementia-free survival than noncarriers.

Our findings argue that people need to actively avert these factors in midlife as a strategy for preserving brain health for more than a decade, said Josef Coresh, MD, PhD, director of the Optimal Aging Institute at NYU Langone. Coresh added that discovering new ways to delay dementia is crucial with 42% of Americans at risk for developing the condition at any time after age 55.

The number of people living with dementia globally is forecast to nearly triple to 153 million by 2050. This projection reflects the scale of the public health challenge as populations age. The ARIC study results identify specific midlife vascular conditions that correlate with long-term brain health outcomes.

Racial and ethnic disparities in dementia risk persist into very old age, showing the need for targeted understanding. Existing research on modifiable risk factors often fails to account for the different underlying causes of dementia. Researchers at Lund University examined how individual risk factors are connected to brain changes associated with Alzheimer's disease and vascular dementia.

Their study involved almost 500 participants who had an average age of 65 and showed no signs of cognitive impairment. Researchers followed the participants for four years, measuring changes in the brain's white matter. Most modifiable risk factors, including smoking, cardiovascular disease, high blood lipids, and high blood pressure, were linked to damage to the brain's blood vessels and a faster accumulation of white matter changes. Diabetes was associated with increased accumulation of amyloid β in the Lund University study. People with lower BMI had faster accumulation of tau in the Lund University study.

Why It Matters

Managing blood pressure, diabetes, and smoking status in midlife correlates with nearly 13 additional years of dementia-free survival, showing a specific window for preventive intervention. The data reveals persistent disparities, as Black participants and men experience shorter dementia-free periods compared to White participants and women even when sharing identical risk profiles. These findings establish a dose-response relationship between vascular health and brain longevity, suggesting that addressing these three modifiable factors could significantly alter long-term cognitive outcomes.