Publications

2022

Kyalwazi AN, Loccoh EC, Brewer LC, Ofili EO, Xu J, Song Y, Maddox KEJ, Yeh RW, Wadhera RK. Disparities in Cardiovascular Mortality Between Black and White Adults in the United States, 1999 to 2019. Circulation. 2022;146(3):211–228. doi:10.1161/CIRCULATIONAHA.122.060199

BACKGROUND: Black adults experience a disproportionately higher burden of cardiovascular risk factors and disease in comparison with White adults in the United States. Less is known about how sex-based disparities in cardiovascular mortality between these groups have changed on a national scale over the past 20 years, particularly across geographic determinants of health and residential racial segregation.

METHODS: We used CDC WONDER (Centers for Disease Control and Prevention's Wide-Ranging Online Data for Epidemiologic Research) to identify Black and White adults age ≥25 years in the United States from 1999 to 2019. We calculated annual age-adjusted cardiovascular mortality rates (per 100 000) for Black and White women and men, as well as absolute rate differences and rate ratios to compare the mortality gap between these groups. We also examined patterns by US census region, rural versus urban residence, and degree of neighborhood segregation.

RESULTS: From 1999 to 2019, age-adjusted mortality rates declined overall for both Black and White adults. There was a decline in age-adjusted cardiovascular mortality among Black (602.1 to 351.8 per 100 000 population) and White women (447.0 to 267.5), and the absolute rate difference (ARD) between these groups decreased over time (1999: ARD, 155.1 [95% CI, 149.9-160.3]; 2019: ARD, 84.3 [95% CI, 81.2-87.4]). These patterns were similar for Black (824.1 to 526.3 per 100 000) and White men (637.5 to 396.0; 1999: ARD, 186.6 [95% CI, 178.6-194.6]; 2019: ARD, 130.3 [95% CI, 125.6-135.0]). Despite this progress, cardiovascular mortality in 2019 was higher for Black women (rate ratio, 1.32 [95% CI, 1.30-1.33])- especially in the younger (age <65 years) subgroup (rate ratio, 2.28 [95% CI, 2.23-2.32])-as well as for Black men (rate ratio, 1.33 [95% CI, 1.32-1.34]), compared with their respective White counterparts. There was regional variation in cardiovascular mortality patterns, and the Black-White gap differed across rural and urban areas. Cardiovascular mortality rates among Black women and men were consistently higher in communities with high levels of racial segregation compared with those with low to moderate levels.

CONCLUSIONS: During the past 2 decades, age-adjusted cardiovascular mortality declined significantly for Black and White adults in the United States, as did the absolute difference in death rates between these groups. Despite this progress, Black women and men continue to experience higher cardiovascular mortality rates than their White counterparts.

Essien UR, Tang Y, Figueroa JF, Litam TMA, Tang F, Jones PG, Patel R, Wadhera RK, Desai NR, Mehta SN, et al. Diabetes Care Among Older Adults Enrolled in Medicare Advantage Versus Traditional Medicare Fee-For-Service Plans: The Diabetes Collaborative Registry. Diabetes care. 2022;45(7):1549–1557. doi:10.2337/dc21-1178

OBJECTIVE: Medicare Advantage (MA), Medicare's managed care program, is quickly expanding, yet little is known about diabetes care quality delivered under MA compared with traditional fee-for-service (FFS) Medicare.

RESEARCH DESIGN AND METHODS: This was a retrospective cohort study of Medicare beneficiaries ≥65 years old enrolled in the Diabetes Collaborative Registry from 2014 to 2019 with type 2 diabetes treated with one or more antihyperglycemic therapies. Quality measures, cardiometabolic risk factor control, and antihyperglycemic prescription patterns were compared between Medicare plan groups, adjusted for sociodemographic and clinical factors.

RESULTS: Among 345,911 Medicare beneficiaries, 229,598 (66%) were enrolled in FFS and 116,313 (34%) in MA plans (for ≥1 month). MA beneficiaries were more likely to receive ACE inhibitors/angiotensin receptor blockers for coronary artery disease, tobacco cessation counseling, and screening for retinopathy, foot care, and kidney disease (adjusted P ≤ 0.001 for all). MA beneficiaries had modestly but significantly higher systolic blood pressure (+0.2 mmHg), LDL cholesterol (+2.6 mg/dL), and HbA1c (+0.1%) (adjusted P < 0.01 for all). MA beneficiaries were independently less likely to receive glucagon-like peptide 1 receptor agonists (6.9% vs. 9.0%; adjusted odds ratio 0.80, 95% CI 0.77-0.84) and sodium-glucose cotransporter 2 inhibitors (5.4% vs. 6.7%; adjusted odds ratio 0.91, 95% CI 0.87-0.95). When integrating Centers for Medicare and Medicaid Services-linked data from 2014 to 2017 and more recent unlinked data from the Diabetes Collaborative Registry through 2019 (total N = 411,465), these therapeutic differences persisted, including among subgroups with established cardiovascular and kidney disease.

CONCLUSIONS: While MA plans enable greater access to preventive care, this may not translate to improved intermediate health outcomes. MA beneficiaries are also less likely to receive newer antihyperglycemic therapies with proven outcome benefits in high-risk individuals. Long-term health outcomes under various Medicare plans requires surveillance.

Krawisz AK, Natesan S, Wadhera RK, Chen S, Song Y, Yeh RW, Jaff MR, Giri J, Julien H, Secemsky EA. Differences in Comorbidities Explain Black-White Disparities in Outcomes After Femoropopliteal Endovascular Intervention. Circulation. 2022;146(3):191–200. doi:10.1161/CIRCULATIONAHA.122.058998

BACKGROUND: Black adults have a higher incidence of peripheral artery disease and limb amputations than White adults in the United States. Given that peripheral endovascular intervention (PVI) is now the primary revascularization strategy for peripheral artery disease, it is important to understand whether racial differences exist in PVI incidence and outcomes.

METHODS: Data from fee-for-service Medicare beneficiaries ≥66 years of age from 2016 to 2018 were evaluated to determine age- and sex-standardized population-level incidences of femoropopliteal PVI among Black and White adults over the 3-year study period. Patients' first inpatient or outpatient PVIs were identified through claims codes. Age- and sex-standardized risks of the composite outcome of death and major amputation within 1 year of PVI were examined by race.

RESULTS: Black adults underwent 928 PVIs per 100 000 Black beneficiaries compared with 530 PVIs per 100 000 White beneficiaries (risk ratio, 1.75 [95% CI, 1.73-1.77]; P<0.01). Black adults who underwent PVI were younger (mean age, 74.5 years versus 76.4 years; P<0.01), were more likely to be female (52.8% versus 42.7%; P<0.01), and had a higher burden of diabetes (70.6% versus 56.0%; P<0.01), chronic kidney disease (67.5% versus 56.6%; P<0.01), and heart failure (47.4% versus 41.7%; P<0.01) than White adults. When analyzed by indication for revascularization, Black adults were more likely to undergo PVI for chronic limb-threatening ischemia than White adults (13 023 per 21 352 [61.0%] versus 59 956 per 120 049 [49.9%]; P<0.01). There was a strong association between Black race and the composite outcome at 1 year (odds ratio, 1.21 [95% CI, 1.16-1.25]). This association persisted after adjustment for socioeconomic status (odds ratio, 1.08 [95% CI, 1.03-1.13]) but was eliminated after adjustment for comorbidities (odds ratio, 0.96 [95% CI, 0.92-1.01]).

CONCLUSIONS: Among fee-for-service Medicare beneficiaries, Black adults had substantially higher population-level PVI incidence and were significantly more likely to experience adverse events after PVI than White adults. The association between Black race and adverse outcomes appears to be driven by a higher burden of comorbidities. This analysis emphasizes the critical need for early identification and aggressive management of peripheral artery disease risk factors and comorbidities to reduce Black-White disparities in the development and progression of peripheral artery disease and the risk of adverse events after PVI.

Warraich HJ, Kumar P, Nasir K, Maddox KEJ, Wadhera RK. Political environment and mortality rates in the United States, 2001-19: population based cross sectional analysis. BMJ (Clinical research ed.). 2022;377:e069308. doi:10.1136/bmj-2021-069308

OBJECTIVE: To assess recent trends in age adjusted mortality rates (AAMRs) in the United States based on county level presidential voting patterns.

DESIGN: Cross sectional study.

SETTING: USA, 2001-19.

PARTICIPANTS: 99.8% of the US population.

MAIN OUTCOME MEASURES: AAMR per 100 000 population and average annual percentage change (APC).

METHODS: The Centers for Disease Control and Prevention WONDER database was linked to county level data on US presidential elections. County political environment was classified as either Democratic or Republican for the four years that followed a November presidential election. Additional sensitivity analyses analyzed AAMR trends for counties that voted only for one party throughout the study, and county level gubernatorial election results and state level AAMR trends. Joinpoint analysis was used to assess for an inflection point in APC trends.

RESULTS: The study period covered five presidential elections from 2000 to 2019. From 2001 to 2019, the AAMR per 100 000 population decreased by 22% in Democratic counties, from 850.3 to 664.0 (average APC -1.4%, 95% confidence interval -1.5% to -1.2%), but by only 11% in Republican counties, from 867.0 to 771.1 (average APC -0.7%, -0.9% to -0.5%). The gap in AAMR between Democratic and Republican counties therefore widened from 16.7 (95% confidence interval 16.6 to 16.8) to 107.1 (106.5 to 107.7). Statistically significant inflection points in APC occurred for Democratic counties between periods 2001-09 (APC -2.1%, -2.3% to -1.9%) and 2009-19 (APC -0.8%, -1.0% to -0.6%). For Republican counties between 2001 and 2008 the APC was -1.4% (-1.8% to -1.0%), slowing to near zero between 2008 and 2019 (APC -0.2%, -0.4% to 0.0%). Male and female residents of Democratic counties experienced both lower AAMR and twice the relative decrease in AAMR than did those in Republican counties. Black Americans experienced largely similar improvement in AAMR in both Democratic and Republican counties. However, the AAMR gap between white residents in Democratic versus Republican counties increased fourfold, from 24.7 (95% confidence interval 24.6 to 24.8) to 101.3 (101.0 to 101.6). Rural Republican counties experienced the highest AAMR and the least improvement. All trends were similar when comparing counties that did not switch political environment throughout the period and when gubernatorial election results were used. The greatest contributors to the widening AAMR gap between Republican and Democratic counties were heart disease (difference in AAMRs 27.6), cancer (17.3), and chronic lower respiratory tract diseases (8.3), followed by unintentional injuries (3.3) and suicide (3.0).

CONCLUSION: The mortality gap in Republican voting counties compared with Democratic voting counties has grown over time, especially for white populations, and that gap began to widen after 2008.

Aggarwal R, Gondi S, Wadhera RK. Comparison of Medicare Advantage vs Traditional Medicare for Health Care Access, Affordability, and Use of Preventive Services Among Adults With Low Income. JAMA network open. 2022;5(6):e2215227. doi:10.1001/jamanetworkopen.2022.15227

IMPORTANCE: The Medicare Advantage (MA) program has doubled in size during the past decade, and enrollment among adults with low income has increased rapidly. Such adults face significant barriers in accessing care, leading to poorer health outcomes. Therefore, understanding how health care access, preventive care, and care affordability compare for adults with low income who are enrolled in MA vs traditional Medicare (TM) is critically important.

OBJECTIVE: To compare measures of health care access, preventive care use, and affordability of care between adults with low income who are enrolled in MA vs TM.

DESIGN, SETTING, AND PARTICIPANTS: This nationally representative cross-sectional study used the 2019 National Health Interview Survey to compare 2622 adults aged 65 years or older with low income who were enrolled in MA vs TM. Data were analyzed from December 5, 2021, to April 10, 2022.

MAIN OUTCOMES AND MEASURES: Measures of health care access, preventive care use, and health care affordability.

RESULTS: The study cohort included 2622 adults aged 65 years or older with low income, resulting in a weighted cohort of 14 222 243 adults, of whom 5 641 049 (39.7%) were enrolled in MA and 8 581 194 (60.3%) in TM. The overall age of the cohort was 74.6 years (95% CI, 74.3-74.9). Between the MA and TM groups, the mean age (74.5 years [95% CI, 74.1-75.0] vs 74.7 years [95% CI, 74.3-75.1]; P = .63) and sex distribution (63.6% women [95% CI, 59.8%-67.3%] vs 60.4% women [95% CI, 57.4%-63.3%]; P = .17) were similar, but adults with low income in MA were more likely to be non-Hispanic Asian (7.6% [95% CI, 5.0%-10.1%] vs 3.8% [95% CI, 2.4%-5.3%]; P = .01) or Hispanic (18.1% [95% CI, 14.3%-21.9%] vs 9.4% [95% CI, 7.2%-11.7%]; P < .001). Adults with low income in MA compared with those enrolled in TM were more likely to have a usual place of care (97.7% vs 94.9%; adjusted odds ratio [aOR], 2.37 [95% CI, 1.38-4.07]), but similarly likely to have a recent physician visit (95.5% vs 93.5%; aOR, 1.39 [95% CI, 0.88-2.17]) and to delay medical care (5.3% vs 5.7%; aOR, 0.83 [95% CI, 0.56-1.24]) or not seek medical care (5.6% vs 5.9%; aOR, 0.86 [95% CI, 0.56-1.30]) due to costs. For preventive care measures, adults with low income in MA were more likely than those in TM to have undergone a recent cholesterol screening (98.7% vs 96.6%; aOR, 2.58 [95% CI, 1.27-5.22]). However, there were no significant differences between the MA and TM groups in the likelihood of diabetes screening (90.6% vs 87.6%; aOR, 1.21 [95% CI, 0.87-1.66]), blood pressure screening (96.8% vs 95.2%; aOR, 1.37 [95% CI, 0.84-2.23]), or receipt of an influenza vaccination in the past year (66.3% vs 63.8%; aOR, 1.16 [95% CI, 0.93-1.45]). Adults with low income in MA or TM were similarly likely to be concerned about paying medical bills (47.3% vs 44.2%; aOR, 1.09 [95% CI, 0.88-1.35]) or have problems paying medical bills (17.1% vs 17.2%; aOR, 0.94 [95% CI, 0.69-1.27]) and were also similarly likely to delay filling prescriptions (7.4% vs 6.2%; aOR, 1.22 [95% CI, 0.78-1.92]) or to not fill prescriptions (7.8% vs 7.4%; aOR, 1.01 [95% CI, 0.70-1.45]) due to costs.

CONCLUSIONS AND RELEVANCE: In this study of Medicare beneficiaries with low income, key measures of health care access, preventive care use, and health care affordability generally did not differ between those enrolled in MA vs TM.

Oseran AS, Sun T, Wadhera RK. Health Care Access and Management of Cardiovascular Risk Factors Among Working-Age Adults With Low Income by State Medicaid Expansion Status. JAMA cardiology. 2022;7(7):708–714. doi:10.1001/jamacardio.2022.1282

IMPORTANCE: Medicaid expansion led to gains in insurance coverage among working-age adults with low income. To date, the extent to which disparities in access and cardiovascular care persist for this population in Medicaid nonexpansion and expansion states is unknown.

OBJECTIVE: To compare insurance coverage, health care access, and cardiovascular risk factor management between working-age adults (age 18-64 years) with low income in Medicaid nonexpansion and expansion states and between uninsured and insured adults in these states.

DESIGN, SETTING, AND PARTICIPANTS: This cross-sectional study analyzed data on adults aged 18 to 64 years with low income from the Behavioral Risk Factor Surveillance System from January 1 to December 31, 2019.

EXPOSURES: State Medicaid expansion and insurance status.

MAIN OUTCOMES AND MEASURES: The main outcomes were health care access and monitoring and treatment of cardiovascular risk factors. The estimated adjusted risk difference (RD) in outcomes was estimated to compare adults in Medicaid nonexpansion and expansion states and uninsured and insured individuals in nonexpansion and expansion states.

RESULTS: The weighted study population consisted of 28 028 451 working-age adults with low income, including 10 094 994 (36.0%) in Medicaid nonexpansion states (63.4% female) and 17 933 457 (64.0%) in expansion states (59.2% female). Adults in nonexpansion states had higher uninsurance rates (42.4% [95% CI, 40.2%-44.7%] vs 23.8% [95% CI, 22.8%-24.8%]), were less likely to have a usual source of care (55.4% [95% CI, 53.1%-57.6%] vs 65.4% [95% CI, 64.3%-66.5%]; adjusted RD, -11.4% [95% CI, -13.9% to -8.8%]) or a recent examination (78.9% [95% CI, 77.0%-80.9%] vs 84.4% [95% CI, 83.5%-85.2%]; RD, -6.2% [95% CI, -8.4% to -4.0%]), and were more likely to have deferred care owing to cost (36.1% [95% CI, 34.0%-38.2%] vs 21.8% [95% CI, 20.9%-22.8%]; RD, 14.2% [95% CI, 11.9%-16.6%]) than were those in expansion states. There were no significant differences in cardiovascular risk factor management between these groups. In nonexpansion states, uninsured adults had significantly worse access to care across these measures and were less likely to receive indicated monitoring of cholesterol (72.6% [95% CI, 67.7%-77.4%] vs 93.7%; [95% CI, 92.4%-95.0%]; RD, -17.2% [95% CI, -21.8% to -12.6%]) and hemoglobin A1c (55.2% [95% CI, 40.0%-72.5%] vs 88.5% [95% CI, 79.2%-97.9%]; RD, -25.8% [95% CI, -47.6% to -4.1%]) levels or to receive treatment for hypertension (49.4% [95% CI, 43.3%-55.6%] vs 74.7% [95% CI, 71.5%-78.0%]; RD, -16.3% [95% CI, -23.2% to -9.4%]) and hyperlipidemia (30.2% [95% CI, 23.5%-36.8%] vs 58.7% [95% CI, 53.9%-63.5%]; RD, -19.3% [95% CI, -27.9% to -10.7%]) compared with insured adults. These patterns were similar for uninsured and insured adults in expansion states.

CONCLUSIONS AND RELEVANCE: In this study, working-age adults with low income in Medicaid nonexpansion states experienced higher uninsurance rates and worse access to care than did those in expansion states; however, cardiovascular risk factor management was similar and treatment rates were low. In nonexpansion states, uninsured adults were less likely to receive appropriate cardiovascular risk factor management compared with insured adults.

Aggarwal R, Bibbins-Domingo K, Yeh RW, Song Y, Chiu N, Wadhera RK, Shen C, Kazi DS. Diabetes Screening by Race and Ethnicity in the United States: Equivalent Body Mass Index and Age Thresholds. Annals of internal medicine. 2022;175(6):765–773. doi:10.7326/M20-8079

BACKGROUND: Racial/ethnic minority populations in the United States have increased rates of diabetes compared with White populations. The 2021 guidelines from the U.S. Preventive Services Task Force recommend diabetes screening for adults aged 35 to 70 years with a body mass index (BMI) of 25 kg/m2 or greater.

OBJECTIVE: To determine the BMI threshold for diabetes screening in major racial/ethnic minority populations with benefits and harms equivalent to those of the current diabetes screening threshold in White adults.

DESIGN: Cross-sectional study.

SETTING: NHANES (National Health and Nutrition Examination Survey), 2011 to 2018.

PARTICIPANTS: Nonpregnant U.S. adults aged 18 to 70 years (n = 19 335).

MEASUREMENTS: A logistic regression model was used to estimate diabetes prevalence at various BMIs for White, Asian, Black, and Hispanic Americans. For each racial/ethnic minority group, the equivalent BMI threshold was defined as the BMI at which the prevalence of diabetes in 35-year-old persons in that group is equal to that in 35-year-old White adults at a BMI of 25 kg/m2. Ranges were estimated to account for the uncertainty in prevalence estimates for White and racial/ethnic minority populations.

RESULTS: Among adults aged 35 years with a BMI of 25 kg/m2, the prevalence of diabetes in Asian Americans (3.8% [95% CI, 2.8% to 5.1%]), Black Americans (3.5% [CI, 2.7% to 4.7%]), and Hispanic Americans (3.0% [CI, 2.1% to 4.2%]) was significantly higher than that in White Americans (1.4% [CI, 1.0% to 2.0%]). Compared with a BMI threshold of 25 kg/m2 in White Americans, the equivalent BMI thresholds for diabetes prevalence were 20 kg/m2 (range, <18.5 to 23 kg/m2) for Asian Americans, less than 18.5 kg/m2 (range, <18.5 to 23 kg/m2) for Black Americans, and 18.5 kg/m2 (range, <18.5 to 24 kg/m2) for Hispanic Americans.

LIMITATION: Sample size limitations precluded assessment of heterogeneity within racial/ethnic groups.

CONCLUSION: Among U.S. adults aged 35 years or older, offering diabetes screening to Black Americans and Hispanic Americans with a BMI of 18.5 kg/m2 or greater and Asian Americans with a BMI of 20 kg/m2 or greater would be equivalent to screening White adults with a BMI of 25 kg/m2 or greater. Using screening thresholds specific to race/ethnicity has the potential to reduce disparities in diabetes diagnosis.

PRIMARY FUNDING SOURCE: Richard A. and Susan F. Smith Center for Outcomes Research in Cardiology.