People who avoided dementia risk factors in middle age had about 13 more dementia-free years in a long-term study published Wednesday in Neurology Open Access. The finding came from about 12,400 middle-aged U.S. participants tracked for about 26 years by NYU Langone Health researchers.
Josef Coresh, a study author and director of the Optimal Aging Institute at NYU Langone Health, said the researchers wanted to summarize the effects of midlife health habits on dementia and give a simplified bottom-line message. He also said, "We found if you had more risk factors, you had an elevated risk of both dementia and mortality."
NYU Langone Health study
The study looked at three vascular risk factors: high blood pressure, diabetes and smoking. At the start, participants had an average age of 56, just over half were women and about 25% were Black. None had signs of vascular cognitive impairment at the start.
Coresh said, "Vascular health in midlife influences Alzheimer’s pathology" and "Treating vascular risk works on both fronts." The study’s estimates moved in both directions: people with the three risk factors had about 18 dementia-free years of their lives, compared with an estimated 30 years for those with no risk factors.
Anna S. Nordvig and Cynthia Carlsson
Anna S. Nordvig, a neurologist at Weill Cornell Medicine and NewYork-Presbyterian, said, "Those three risk factors are all known to contribute to both small and large blood vessel disease in the brain" and "Controlling anything that improves cardiovascular health will also improve brain health." Cynthia Carlsson, a geriatrician at University of Wisconsin Health, said, "I encourage people to start with something tangible" and "It’ll be different for each person based on what their risk profile looks like."
The study defined high blood pressure as 140/90 mm Hg or higher. For people with all three risk factors, dementia risk rose from 23% at age 55 to 37% at age 75, and by age 85 only 7% were dementia-free. The research points to vascular health rather than all causes of dementia, so the estimate is a midlife risk profile linked to longer time without dementia, not a guarantee for any one person.
Midlife vascular health
The result gives patients and clinicians a concrete target: blood pressure, diabetes and smoking in midlife. Coresh said, "There’s a lot you can do." The study narrows that advice to three common risks that can be addressed earlier, when the years gained without dementia were largest in the comparison between people with and without those risks.
