Scientists claim to have identified three health measures in middle age that can ward off dementia for more than a decade.
Having normal blood pressure, no type 2 diabetes, and not smoking between the ages of 45 and 65 were associated with almost 13 additional years, on average, of dementia-free life, a study shows.
The research also suggested that, no matter how many risk factors people had, women lived longer without dementia than men, and that white people had more dementia-free years than black people.
The findings were published in the medical journal Neurology.
Researchers from NYU Langone Health analysed data from the Atherosclerosis Risk in Communities (Aric) study, which began in 1986 and followed Americans for decades into late life, measuring midlife vascular risk factors and dementia.
In the new analysis, researchers looked at 12,409 people with an average age of 56 who were free of dementia. Participants were assessed for three risk factors: high blood pressure, type 2 diabetes, and smoking. They were then followed for about three decades, with an average follow-up of 26 years.
During that time, 3,008 developed dementia and 5,238 died without developing the condition.
Those who had none of the three risk factors lived without developing dementia almost 13 years longer than those who had all three.
Those with no diabetes, no high blood pressure and who did not smoke at the start of the study had an average of 30.1 more years free of dementia, the study found.
Meanwhile, those with one risk factor had an extra 26.3 years, those with two had 21 years, and those with three had just over 17 years.
“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 senior investigator Dr Josef Coresh, director of the Optimal Aging Institute at NYU Langone.
“Hopefully, these results will encourage people to stop smoking and watch their vascular health closely from age 45 on.”
The number of people living with dementia globally is forecast to nearly triple to 153 million by 2050. But experts believe almost half of dementia cases worldwide could be prevented or delayed.
Previous research has suggested that addressing 14 modifiable risk factors, starting in childhood and continuing throughout life, could prevent or delay 45% of dementia cases, even as people live longer.
The NYU Langone study said the three factors it identified “often emerge in midlife” and “exert lasting effects on neurodegenerative pathology”, underscoring the critical importance of early identification and management.
Dr Jacqui Hanley, head of research funding at Alzheimer’s Research UK, who was not involved with the research, said: “Rather than focusing only on the chances of developing dementia, this study asks a question that matters to people: how long can we expect to live free from dementia?
“This approach gives a meaningful picture of how midlife health may shape the number of years we spend living free from dementia, while also recognising that high blood pressure, diabetes and smoking are linked to a higher likelihood of dementia as well as a greater risk of dying earlier from other conditions.
“These findings emphasise why it’s so important to look after your heart health as well as your brain health.”
Hanley said everyone should take practical steps, including staying physically active, not smoking, and managing conditions such as high blood pressure and diabetes.
“While there is no guaranteed way to prevent dementia, research, including this study, suggests that addressing risk factors for poor cardiovascular health may also help reduce the risk of cognitive decline and dementia.”
