Diabetes and hypertension could have a domino effect for future health problems like dementia - especially for Black Americans, according to a new University of Georgia study.
The study found that Black Americans diagnosed with both conditions in midlife had significantly higher levels of a dementia-related biomarker more than a decade later.
"This matters. This study shows that chronic conditions like high blood pressure and diabetes, especially when combined together, might start damaging the brain earlier than we thought, especially for this group," said Rachael Weaver, corresponding author of the study and a graduate student in the UGA Franklin College of Arts and Sciences department of sociology.
"When these two conditions show up together in midlife, they might start a chain reaction leading to brain aging even as much as a decade later."
Cardiovascular health may be an indicator of degenerative brain diseases like dementia
Black Americans historically show cognitive decline at higher rates and at earlier ages than white people. Uncovering physical conditions that accelerate this is crucial for improving quality of life and health outcomes, the researchers said.
The study followed more than 250 participants with high blood pressure, diabetes or both conditions.
The researchers found that while one diagnosis alone did not indicate a dramatic neurological effect, having both led to striking results.
Taking steps early to control high blood pressure and diabetes may help protect African Americans from brain degeneration and lower their risk of dementia." -Karlo Lei, Franklin College of Arts and Sciences
Those with diabetes and hypertension at midlife had elevated levels of a biomarker of dementia. Both of these diagnoses not only contributed to higher amounts of that biomarker but also a greater increase of it over an 11-year period.
"The study sends a clear message: Taking steps early to control high blood pressure and diabetes may help protect African Americans from brain degeneration and lower their risk of dementia later in life," said Karlo Lei, co-author of the study and an associate professor in the Franklin College department of sociology.
The findings suggest that health practitioners should place a higher focus on cardiovascular health as an indicator of dementia risk, especially among Black Americans, the researchers said.
"This distinction is important because it suggests that strategies aimed at preventing or slowing cognitive decline in Black Americans may need to prioritize prevention and management of vascular diseases beginning in midlife," said Mei Ling Ong, co-author of the study and an associate research scientist in the UGA Center for Family Research.
"Early intervention for these chronic health conditions could significantly protect brain health and reduce the incidence of neurodegenerative diseases later in life."
Public health education in at-risk communities needed
Many of the study participants with cardiovascular issues also reported low incomes. Nearly one in five of the participants also had less than a 12th grade education. This highlights a key relationship between socioeconomic status and health outcomes.
"Health inequities like the ones that we're exploring are not inevitable. They are very systemic, and they're potentially preventable. Just as crucial as early screening and treatment is the need for change that addresses the structural inequities putting Black Americans at higher risk in the first place," said Weaver.
Highlighting the connection between heart and brain health could also help encourage people to exercise, reduce their stress levels, eat healthier and limit smoking and alcohol, the researchers said.
This study was funded by the National Institute on Aging and the National Heart, Lung, and Blood Institute. Co-authors include Steven Beach, Regents Professor of Psychology in the Franklin College; Yu-Wen Lu, a graduate student in the Franklin College; and the late Ron Simons, Regents Professor in the UGA Department of Sociology, who passed away in March. Additional co-authors include Michelle M. Mielke.
