The National Institutes of Health (NIH) reports that dementia affects more than 6 million older adults and accounts for more than 100,000 deaths every year in the United States. Among the various types, vascular-related dementia is strongly tied to cardiometabolic risk factors and may be preventable with earlier intervention, especially for Black patients.
Black people are about twice as likely to develop Alzheimer’s disease and related dementia as their white counterparts, but are 35% less likely to be diagnosed. Vascular-related risk factors (e.g., diabetes, hypertension, and obesity), socioeconomic disadvantages, chronic stress from racism, and underrepresentation in clinical trials are the main drivers for these health disparities.
High body mass index (BMI) is associated with a higher risk for vascular-related dementia, with the association partially mediated by high blood pressure, according to a study published online Jan. 22 in the Journal of Clinical Endocrinology & Metabolism.
Liv Tybjærg Nordestgaard, M.D., Ph.D., from Copenhagen University Hospital-Rigshospitalet in Denmark, and colleagues examined whether high BMI is a causal risk factor for vascular-related dementia in prospective cohort studies of the general populations from the Copenhagen area and from across the United Kingdom, using consortia data. One-sample Mendelian randomization (MR), two-sample MR, and MR in mediation analyses were included as interventions.
The researchers found that the odds ratio for one-standard deviation higher BMI in predicting vascular-related dementia was 1.63 in a meta-analysis of two one-sample MR studies. Per one-standard deviation higher BMI, the odds ratio for vascular-related dementia was 1.54, 1.87, and 1.98 using the inverse-variance weighted, weighted median, and weighted mode methods, respectively, in a two-sample MR study. Directionally consistent results were seen for MR analyses, including an extended number of genetic variants. Systolic and diastolic blood pressure mediated 18 and 25 percent, respectively, of the genetic effect of BMI on vascular-related dementia.
“This study shows that high body weight and high blood pressure are not just warning signs, but direct causes of dementia,” coauthor Ruth Frikke-Schmidt, M.D., also from Copenhagen University Hospital-Rigshospitalet, said in a statement. “That makes them highly actionable targets for prevention.”
Why Vascular-Related Dementia Disproportionately Affects Black Patients
Black Americans have higher rates of hypertension, obesity, and type 2 diabetes, all of which are vascular risk factors that can contribute to dementia risk.
Additionally, dementia in Black patients tends to be vascular-related or mixed dementia rather than just solely Alzheimer’s. Because vascular dementia is more preventable than neurodegenerative dementia, early management of risk factors could have a significant impact on this patient population.
Providers should recognize that an elevated BMI in Black patients may not only indicate their risk for cardiometabolic disease, but also long-term cognitive risk.
Improving Hypertension Management
The researchers found that blood pressure was a major contributor to the BMI-dementia relationship. These findings have many practical implications for clinicians.
Black adults can develop hypertension much earlier than other racial or ethnic groups, and often with greater severity. Additionally, they are more likely to have treatment-resistant hypertension. As a result, vascular-related brain injuries may develop several decades before cognitive symptoms even appear.
Intensive blood pressure control—particularly during midlife—could be one of the most effective dementia prevention strategies for Black adults.
Providers serving Black patients should consider:
- Earlier dementia screening
- Stricter follow-ups
- Combination antihypertensive therapy when appropriate
- Addressing any barriers relating to affordability or treatment adherence
Navigating Stigma
Counseling patients about weight can be a sensitive topic, especially for Black patients who have historically faced bias and medical gaslighting from healthcare professionals. In fact, a survey found that Black patients were significantly less likely to avoid care due to a fear of discussing weight or being weighed than white patients.
Clinicians can encourage Black patients engage in dementia prevention by framing weight management around cognitive health rather than their physical appearance or specific BMI targets.
Clinicians can focus the conversation on:
- Preserving memory and independence
- Preventing vascular-related cognitive impairment
- Protecting long-term quality of life
This approach takes some of the focus off the numbers and homes in on patient-centered care and risk reduction of vascular-related dementia.
The Importance of Screening and Earlier Cognitive Evaluations
Since Black patients are less likely to be diagnosed with dementia despite having a higher prevalence of the age-related disease, providers should reduce the criteria typically required for cognitive screenings in patients with multiple cardiometabolic risk factors.
Older patients with hypertension, obesity, diabetes, or a history of stroke may benefit from earlier cognitive assessment—especially if they or loved ones report subtle changes in their cognitive function.
The Takeaway
This study highlights that, in most cases, vascular dementia is preventable. For Black patients who face higher vascular risk and lower diagnosis rates, the proper prevention strategies are essential to reduce their risk.
Monitoring cardiometabolic health should be part of not only cardiovascular care, but also long-term brain health for Black patients.