Many stroke risk factor disparities exist between Black and white Americans; Black people are 50 percent more likely to have a stroke than white people, according to the U.S. Department of Health and Human Services Office of Minority Health.
But a new retrospective analysis shows that access to routine medical care and lifestyle modification coaching can help close that gap. In a study published August 3 in the journal Stroke, researchers found that aggressive management of blood pressure, cholesterol, and diabetes — along with a lifestyle modification program to manage weight and increase physical activity — successfully reduced some of those risk factors for stroke and reduced the disparity in outcomes between racial groups.
Health Disparities for Black Stroke Survivors
Before the intervention began, there were significant modifiable stroke risk factor differences between Black and non-Black adults who previously had a stroke, says a study coauthor, Ashley Nelson, DO, a fellow in neurocritical care at the School of Medicine and Dentistry at the University of Rochester in New York.
“However, after one year of intensive medical intervention that included routine access to healthcare, tailoring medications, and lifestyle modification coaching, some of those risk factors were no longer present, suggesting that this type of risk factor management may have an important role in improving or eliminating underlying disparities in vascular risk factors for secondary stroke prevention,” says Dr. Nelson.
At the end of one year on this plan, there was no difference between Black and non-Black patients in blood pressure, cholesterol, diabetes, or activity metrics, says Amy Guzik, MD, a neurologist and stroke expert at Atrium Health Wake Forest Baptist in Winston-Salem, North Carolina.
“The key here is that having a structured, well-defined plan to address stroke risk factors not only ensured that all patients received equal care, but reversed the disparities seen between Black and non-Black patients,” says Dr. Guzik, who was not involved in the study.
Black Americans and Stroke Risk
Black Americans have a higher prevalence of stroke and the highest death rate from stroke of all racial groups, according to the American Stroke Association (ASA).
On top of that, Black stroke survivors are more likely to be disabled and have difficulties doing daily activities, per the ASA.
It’s not clear why this disparity exists, but experts agree that it’s likely to be due to a combination of factors. About 2 out of 3 Black Americans have at least one of the following risk factors for stroke:
- High blood pressure More than half of Black adults have high blood pressure. By age 55, 3 out of 4 Black adults have already developed this condition, compared with about 50 percent of white men and 40 percent of white women.
- Overweight and obesity Almost 70 percent of Black men and more than 80 percent of Black women have overweight or obesity.
- Diabetes African Americans are 60 percent more likely to be diagnosed with diabetes than non-Hispanic whites, according to the U.S. Department of Health and Human Services Office of Minority Health (OMH).
- High cholesterol Nearly 30 percent of Black Americans have high levels of “bad” LDL cholesterol.
- Sickle cell anemia This common genetic disorder is a risk factor for stroke.
- Smoking Over 15 percent of Black adults smoke, which doubles the risk of stroke.
- A high-salt (sodium) diet Research shows that Black Americans may have a gene that greatly increases sensitivity to salt and its effects. Salt sensitivity is present in nearly 3 in 4 Black Americans with hypertension, per OMH.
- Stress and structural racism African Americans have unique stressors that may increase stroke risk. Additionally, Black people are more likely to have difficulty accessing healthy foods, clean air, areas to exercise, and healthcare than their white counterparts.
Disparities in Risk Factors Between Races Were Observed Before the Intervention
Researchers used health data from the SAMMPRIS (Stenting and Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis) study. All the participants in that trial had experienced a stroke caused by severe intracranial atherosclerotic stenosis, which is a narrowing of a major brain artery by at least 70 percent.
In this follow-up analysis, researchers compared medication use and vascular risk factors, such as systolic blood pressure, diastolic blood pressure, low-density lipoprotein, blood glucose levels, and physical activity levels of Black and non-Black adults at baseline (before the study) and then after one year of aggressive medical management and a lifestyle modification program.
At the time of recruitment, there were a total of 451 participants; 104 were Black and 347 were not Black. This study didn’t compare Black adults to any other specific racial subgroup because there weren’t enough people of each race in the study. Non-Black participant groups included white, Asian, and Hispanic adults who were measured collectively, according to the authors.
Significant differences were observed at enrollment in the study between Black participants and non-Black participants:
- Age Black participants were younger: 57 years old versus 61 years old.
- High blood pressure 95.2 percent of African Americans had hypertension, versus 87.5 percent of non-Black participants.
- Type 2 diabetes 52.9 percent of Black participants versus 39.7 percent of non-Black participants had type 2 diabetes.
- Diastolic blood pressure The Black Americans had a higher average diastolic blood pressure, at 82.4 millimeters of mercury (mmHg), than the non-Black participants, at an average of 79.5 mmHg.
- Physical activity Black participants had lower physical activity PACE scores, at 2.7 versus 3.3 for the non-Black participants. A PACE score of 4 or above is considered moderately active and within the target range.
Physical activity was measured with the physician-based assessment and counseling for exercise (PACE) score. Physical activity out of target was defined as a PACE score of 3 or less, which was given to people who attempted moderate or vigorous exercise but not regularly.
In-target physical activity was defined as PACE score of least 4, which was defined as moderate exercise fewer than five times per week or vigorous exercise fewer than three times per week). Moderate exercise was defined as brisk walking, gardening, or slow cycling for at least 10 minutes. Vigorous exercise was defined as jogging, running, or fast cycling for at least 20 minutes.
“We know that disparities exist in stroke risk, and even in the care that people receive to prevent stroke,” says Dr. Guzik. “In this study, we see that at the baseline, Black patients with stroke were younger, were more likely to have a history of diabetes and hypertension, and had lower rates of physical activity compared to non-Black patients with stroke,” she says.
Intervention Was Linked to Improvements in Diastolic Blood Pressure and Physical Activity
At the end of the study, researchers were able to collect data from 83 Black participants and 265 non-Black participants. After one year of following a well-defined intensive intervention, the disparity in diastolic blood pressure no longer existed. The average diastolic blood pressure in Black adults dropped to 74.7 mmHg, compared with 75.5 mmHg in all other participants.
The percentage of thiazide diuretic medication use doubled in Black participants, which could explain the notable decrease in average diastolic blood pressure, according to the authors.
Blood pressure is measured using two numbers: The first number, called systolic blood pressure, measures the pressure in your arteries when your heart beats. The second number, called diastolic blood pressure, measures the pressure in your arteries when your heart rests between beats. Both blood pressure numbers matter when it comes to cardiovascular events and health, according to the American Heart Association.
Additionally, physical activity measures were essentially the same between the groups, with the average PACE score increasing among Black adults to 4.2 from 2.7; in comparison, the average PACE score among non-Black adults was 4.1.
Study Shows That Structured, Personalized Care Could Improve Health Disparities
This study shows that this type of structured, focused management not only lowers stroke risk in all groups, but likely reduces the disparity in risk between Black and non-Black patients by eliminating the gap in blood pressure, cholesterol, and diabetes control and physical activity, says Guzik.
What Would ‘Intensive Management’ Look Like in the Real World?
“Practical use of this protocol would include regular medical follow-up three to four times per year to ensure blood pressure, cholesterol, and hemoglobin A1C measurements were at goal and to make medication dosing adjustments or transitions if appropriate,” says Nelson.
In addition to consistent medical follow-up, patients would be referred to or enrolled in lifestyle modification programs to encourage people to stop smoking, make healthy dietary adjustments, and increase exercise levels if needed, she adds.
It’s essential to provide patients and clinicians with tools to lower stroke risk in those most affected, says Guzik. “Implementation and reimbursement of management plans that reduce and eliminate the disparities in stroke risk between Black and non-Black patients must be prioritized to ensure effective stroke care for all patients, regardless of background,” she says.