More than one-third of dementia cases in the U.S. are linked to heart and metabolic conditions like diabetes, high blood pressure, and stroke, according to a new national study. Older Americans in Southern states are most affected.
Researchers analyzed Medicare claims data from nearly 21 million Americans aged 67 and older, uncovering that 37% of dementia cases are associated with eight preventable or manageable health conditions: diabetes, heart failure, atrial fibrillation, coronary artery disease, heart attack, stroke, high blood pressure, and high cholesterol.
The findings were published this week in the journal Alzheimer’s & Dementia and led by Dr. Brad Racette, chair of neurology at the Barrow Neurological Institute in Phoenix.
“A substantial number of dementia cases could be eliminated by mitigating modifiable cardiometabolic risk factors, especially in U.S. counties with a high risk of dementia attributed to these risk factors,” Racette said.
Among all conditions studied, stroke carried the strongest link to dementia, raising the risk more than twofold. Heart failure followed closely with a 2.1-times increased risk. High blood pressure increased the odds by 78%, while high cholesterol — the least impactful — was still linked to a 27% increased risk.
If the nation managed to reduce these risk factors by just 15%, Racette estimates that new dementia cases could decline by more than 6%.
The South stood out as the region most affected. County-level data showed that Americans in Southern states face the greatest dementia risk linked to cardiovascular and metabolic disease. Researchers pointed to regional lifestyle factors like obesity, poor diet, and lack of physical activity as major contributors.
Meanwhile, residents of the Pacific Northwest, the Great Plains, and the Rocky Mountain region showed far lower dementia risk tied to these conditions.
With nearly 800,000 dementia cases examined, the research reinforces the connection between long-term heart health and brain function — and highlights what many doctors have long warned: treating conditions like hypertension, diabetes, and stroke risk may not only protect the heart, but also help preserve memory and cognitive health in old age.