Healthy lifestyle choices can offset genetic risk for brain diseases

Christopher D. Anderson, MD, MSc, chief of the Division of Stroke and Cerebrovascular Diseases at Brigham and Women's Hospital and associate neurologist in the Department of Neurology and Center for Genomic Medicine at Massachusetts General Hospital, is the corresponding author and Jonathan Rosand, MD, MSc, co-founder of the McCance Center for Brain Health and neurologist in the Department of Neurology and Center for Genomic Medicine at Massachusetts General Hospital, is an author of a paper published on November 6, 2024, in Neurology^®, the medical journal of the American Academy of Neurology, "Health-related behaviors and risk of common age-related brain diseases across severities of genetic risk."

How would you summarize your study for a lay audience?

In this study, we explored whether healthy lifestyle choices, measured by a Brain Care Score (BCS), can lower the risk of stroke, late-life depression (LLD) and dementia, in individuals who are genetically predisposed to these conditions. Developed by Mass General Brigham researchers, the BCS is a brain health tool that measures healthy lifestyle choices in the form of a score that then reflects combined risk for the most common causes of age-related brain health conditions.

From the data we analyzed, we found in individuals with a higher BCS, which reflects healthier habits, had a significant decrease in their risk of stroke, LLD and dementia even when they had a higher genetic predisposition to these conditions. This protective lifestyle effect was strong enough to offset the increased risk from genetics. Our findings suggest that individuals who adopt healthy lifestyle choices can protect their brain health, regardless of their genetic risk.

How does your new study differ from your previous publications?

In previous research, we found a higher BCS is associated with a decreased risk of stroke, LLD and dementia. In this study, we discovered that this association extends to individuals who are genetically predisposed to these brain conditions.

How did you conduct your study?

In this study, we examined whether an individual's BCS affects their genetic risk of stroke, LLD and dementia. After analyzing data from over 368,000 individuals in the UK Biobank, we discovered that a higher BCS significantly reduced the risk of stroke, late-life depression and dementia in individuals who had inherited an increased genetic risk for those conditions. Strikingly, we found that even a small 5-point increase in the BCS, through steps such as quitting smoking or controlling blood pressure, is strongly linked to a lower risk of brain diseases.

What are the implications?

Our work emphasizes how powerful healthy lifestyle choices can be, even for those of us who, because of our genes, are at higher risk of deterioration in our brain health as we age. For all of us, including those with higher genetic risk, the BCS offers a simple and direct guide to what we can do to protect our brains as we age. Patients can feel empowered to continue to modify behaviors to improve their health outcomes, regardless of their genetic risk.

What are the next steps?

We are working to update the BCS to make it even more user-friendly, allowing people to identify areas where they can improve their brain care without requiring detailed information about their medical histories. We are also studying how best to engage communities around the world with brain care tools that can enable them to take good care of their brains, prevent dementia, stroke, and depression, and thereby help themselves and their loved ones to flourish.

Authorship: In addition to Anderson and Rosand, Mass General Brigham authors include Sandro Marini, Tamara N. Kimball, Ernst Mayerhofer, Reinier W.P. Tack, Jasper R. Senff, Savvina Prapiadou, Jonathan Duskin, Christina Kourkoulis, Nirupama Techoor, Rudolph E. Tanzi, Sanjula D. Singh and Livia Parodi.