Stroke Mortality Among Black and White Adults Aged ≥35 Years Before and During the COVID-19 Pandemic — United States, 2015–2021
By Quanhe Yang, PhD, Xin Tong, MPH, Linda Schieb, MSPH, Fátima Coronado, MD, Robert Merritt, MS
On April 21, 2023
Summary
What is already known about this topic?
Stroke is the fifth leading cause of death and a leading cause of long-term disability in the United States. During 1999–2019, non-Hispanic Black or African American (Black) adults experienced consistently higher stroke death rates than did non-Hispanic White (White) adults.
What is added by this report?
During the COVID-19 pandemic, age-adjusted stroke mortality rates increased among both Black and White adults; however, the absolute difference between Black and White adults was 21.7% higher than during the prepandemic period. The percentage of excess stroke deaths during the pandemic was higher among Black (9.4%) than among White (6.9%) adults.
What are the implications for public health practice?
Identifying the health care, behavioral, and contextual factors associated with these widened disparities and providing tailored interventions are necessary to reduce disparities in stroke mortality among Black and White adults.
Stroke is the fifth leading cause of death and a leading cause of long-term disability in the United States (1). Although stroke death rates have declined since the 1950s, age-adjusted rates remained higher among non-Hispanic Black or African American (Black) adults than among non-Hispanic White (White) adults (1,2). Despite intervention efforts to reduce racial disparities in stroke prevention and treatment through reducing stroke risk factors, increasing awareness of stroke symptoms, and improving access to treatment and care for stroke (1,3), Black adults were 45% more likely than were White adults to die from stroke in 2018.* In 2019, age-adjusted stroke death rates (AASDRs) (stroke deaths per 100,000 population) were 101.6 among Black adults and 69.1 among White adults aged ≥35 years. Stroke deaths increased during the early phase of the COVID-19 pandemic (March–August 2020), and minority populations experienced a disproportionate increase (4). The current study examined disparities in stroke mortality between Black and White adults before and during the COVID-19 pandemic. Analysts used National Vital Statistics System (NVSS) mortality data accessed via CDC WONDER† to calculate AASDRs among Black and White adults aged ≥35 years prepandemic (2015–2019) and during the pandemic (2020–2021). Compared with that during the prepandemic period, the absolute difference in AASDR between Black and White adults during the pandemic was 21.7% higher (31.3 per 100,000 versus 38.0). During the pandemic period, an estimated 3,835 excess stroke deaths occurred among Black adults (9.4% more than expected) and 15,125 among White adults (6.9% more than expected). These findings underscore the importance of identifying the major factors contributing to the widened disparities; implementing prevention efforts, including the management and control of hypertension, high blood cholesterol, and diabetes; and developing tailored interventions to reduce disparities and advance health equity in stroke mortality between Black and White adults. Stroke is a serious medical condition that requires emergency care. Warning signs of a stroke include sudden face drooping, arm weakness, and speech difficulty. Immediate notification of Emergency Medical Services by calling 9-1-1 is critical upon recognition of stroke signs and symptoms.
Annual AASDRs (calculated using 2000 U.S. Census Bureau standard population) and 95% CIs for Black and White adults aged ≥35 years were calculated for 2015–2020 (using final underlying cause of death data stratified by bridged-race categories) and 2021 (using underlying cause of death data stratified by single-race categories as of March 20, 2023) using CDC WONDER mortality data based on place of residence data from death certificates filed in the 50 U.S. states and the District of Columbia. AASDRs and 95% CIs were then calculated for the prepandemic and pandemic periods. International Classification of Diseases, Tenth Revision cause of death codes I60–I69 (cerebrovascular disease) were used to classify stroke as the underlying cause of death. This study included persons listed as having one race (Black or White) and non-Hispanic or Latino ethnicity.§ Disparities between Black and White adults were measured using absolute and relative differences. The absolute difference in AASDR among adults aged ≥35 years (rate among Black adults minus rate among White adults) was calculated for the prepandemic and pandemic periods and compared. The relative difference was measured by rate ratios calculated as AASDR among Black adults divided by AASDR among White adults. The 95% CIs for the absolute and relative differences were estimated. Nonoverlapping 95% CIs for rates, absolute differences, or relative differences between two periods or two groups (e.g., women versus men) were considered statistically significant. Analyses were stratified by sex and age group (35–64, 65–84, and ≥85 years).
Excess stroke deaths for Black and White adults during the pandemic were estimated as follows: 1) annual percent changes (APC) in the sex-, age-, and race and ethnicity–specific stroke death rates during 2015–2019 were estimated; 2) expected rates for 2020 and 2021 were calculated, assuming the APC during 2015–2019 would continue during 2020–2021; 3) the expected number of stroke deaths was obtained by multiplying the sex-, age-, and race and ethnicity–specific population by the expected stroke death rates; and 4) excess stroke deaths were calculated as the number of stroke deaths observed minus the number expected¶ (5). Analyses were conducted using SAS software (version 9.4; SAS Institute) and Joinpoint (version 4.8.1.0; National Cancer Institute). This activity was reviewed by CDC and was conducted consistent with applicable federal law and CDC policy.**
During 2015–2019, AASDR remained consistent for both Black (range = 100.5–102.0 [with a slight trend of increased rates]) and White adults (range = 69.1–70.6 [with a slight trend of decreased rates]); the average absolute difference was 31.3 per 100,000, and the average relative difference was 1.4. The relative differences in stroke mortality between Black and White adults were higher among men than women, and decreased with increasing age (Table 1) (Figure). During the COVID-19 pandemic, AASDR increased among both populations, but the increase was larger among Black adults; the average AASDR among Black adults increased 11.2% (from 101.3 to 112.6), compared with 6.6% (from 70.0 to 74.6) among White adults. The absolute difference in AASDR between Black and White adults increased 21.7% (from 31.3 to 38.0), and the average relative difference increased to 1.5. The patterns of increased disparities in stroke mortality, as measured by percent change in absolute differences, during the pandemic were similar among men and women and increased with increasing age. The absolute difference in AASDR between Black and White adults increased 10.9% (from 16.6 to 18.4) among persons aged 35–64 years and 19.4% (from 89.8 to 107.2) among persons aged 65–84 years. During the prepandemic period, annual stroke mortality rates among persons aged ≥85 years were lower among Black than among White adults (2). The absolute difference in this age group changed from −23.7 during 2015–2019 to 30.3 per 100,000 during 2020–2021 (Table 1). During 2020–2021, an estimated 3,835 excess stroke deaths occurred among Black adults (9.4% more than expected), and 15,125 excess stroke deaths occurred among White adults (6.9% more than expected). The estimated percentage of excess stroke deaths among both Black and White adults was higher among women and decreased with increasing age (Table 2).
Discussion
This analysis found that in the United States, disparities among Black and White adults in stroke mortality widened from the prepandemic period to the pandemic period. Although stroke mortality increased among both Black and White adults, the absolute difference in AASDRs between the groups increased an estimated 21.7%; this pattern was similar in men and women. The estimated percentage of excess stroke deaths during the pandemic period among Black adults (9.4%) was higher than that among White adults (6.9%). The disparity, measured by absolute difference in AASDR, among adults aged 35–54 years increased approximately 11%, and among adults aged 65–84 years, increased 19%; the lower stroke mortality among Black adults aged ≥85 years during the prepandemic period reversed during the pandemic period.
Disparities in stroke mortality among Black and White adults are largely driven by differences in stroke incidence, with higher prevalences of high blood pressure and diabetes being the major risk factors for stroke among Black adults (1,2,6); racial differences in case-fatality played a minor role (2,6). The COVID-19 pandemic caused a substantial shift in health care for patients with high blood pressure and might have exacerbated existing inequities in high blood pressure treatment and control among persons of color (7). Reduced emergency department visits and hospitalizations for stroke, partly because of fear of SARS-CoV-2 infections (especially during the early phase of the pandemic) (8), suggest that delayed stroke treatment and care might have resulted in worse stroke outcomes and increased risk for death. Further, health and lifestyle behaviors, such as mental health, physical activity, and diet and sleep quality were adversely affected by the pandemic and might have disproportionately affected persons of color, resulting in increased risk for stroke (4). COVID-19 is associated with increased risk for stroke (9); disproportionately higher rates of COVID-19 experienced by Black persons†† (10) might have contributed to the widened disparity among Black and White adults in stroke mortality.
All references linked below.
This piece was republished from the CDC.gov.