Keeping your blood pressure in a healthy range, avoiding diabetes and not smoking during middle age may do much more than protect your heart.
A large new study suggests these healthy habits could also help people stay free from dementia for many more years. The findings were published in Neurology Open Access.
Dementia is not a single disease but a group of conditions that gradually damage memory, thinking and the ability to carry out everyday activities. Alzheimer’s disease is the most common form, but blood vessel disease can also play a major role. As people live longer, preventing dementia has become one of the biggest public health goals.
Researchers from NYU Langone Health wanted to understand how common health problems in middle age affect brain health later in life. They focused on three well-known risk factors: high blood pressure, diabetes and smoking. All three damage blood vessels, including those that supply oxygen and nutrients to the brain.
The team analysed information from the Atherosclerosis Risk in Communities (ARIC) Study, a long-running project that began in 1986. The current analysis included 12,409 adults with an average age of 56 who did not have dementia when the study started. Participants were followed for an average of 26 years.
During the study, 3,008 people developed dementia and 5,238 died without ever developing the condition. Researchers compared how long people remained alive without dementia depending on how many of the three risk factors they had in midlife.
The difference was striking. People who had none of the three risk factors stayed free of dementia for about 30 years after entering the study. Those with all three risk factors remained dementia-free for only about 17 years, a difference of nearly 13 years.
The researchers also found differences between population groups. Women remained free from dementia for longer than men, even when both had the same number of risk factors. White participants also had more dementia-free years than Black participants, highlighting ongoing health inequalities.
Senior author Dr. Josef Coresh said the results suggest that protecting blood vessel health during middle age may help preserve brain health for more than a decade. He noted that about 42% of Americans may develop dementia after age 55, making prevention especially important.
Although the findings are encouraging, the study cannot prove that avoiding these risk factors directly prevents dementia. It only shows that they were strongly linked. Another limitation is that blood pressure, diabetes and smoking status were measured only once, so changes over time were not included.
Even so, the results support existing advice for healthy aging. Keeping blood pressure under control, preventing or managing diabetes, avoiding smoking, exercising regularly and eating a balanced diet all benefit the heart and may also protect the brain.
This is a strong study because it followed more than 12,000 people for over two decades, allowing researchers to examine long-term health outcomes.
However, as an observational study it cannot prove cause and effect. Future research will need to test whether intensive treatment of vascular risk factors during middle age can directly delay dementia.
