Publications by Year: 2022

BACKGROUND: U.S. policy efforts have focused on reducing rural-urban health inequities. However, it is unclear whether gaps in care and outcomes remain among older adults with acute cardiovascular conditions.

OBJECTIVES: This study aims to evaluate rural-urban differences in procedural care and mortality for acute myocardial infarction (AMI), heart failure (HF), and ischemic stroke.

METHODS: This is a retrospective cross-sectional study of Medicare fee-for-service beneficiaries aged ≥65 years with acute cardiovascular conditions from 2016 to 2018. Cox proportional hazards models with random hospital intercepts were fit to examine the association of presenting to a rural (vs urban) hospital and 30- and 90-day patient-level mortality.

RESULTS: There were 2,182,903 Medicare patients hospitalized with AMI, HF, or ischemic stroke from 2016 to 2018. Patients with AMI were less likely to undergo cardiac catherization (49.7% vs 63.6%, P < 0.001), percutaneous coronary intervention (42.1% vs 45.7%, P < 0.001) or coronary artery bypass graft (9.0% vs 10.2%, P < 0.001) within 30 days at rural versus urban hospitals. Thrombolysis rates (3.1% vs 10.1%, P < 0.001) and endovascular therapy (1.8% vs 3.6%, P < 0.001) for ischemic stroke were lower at rural hospitals. After adjustment for demographics and clinical comorbidities, the 30-day mortality HR was significantly higher among patients presenting to rural hospitals for AMI (HR: 1.10, 95% CI: 1.08 to 1.12), HF (HR: 1.15; 95% CI: 1.13 to 1.16), and ischemic stroke (HR: 1.20; 95% CI: 1.18 to 1.22), with similar patterns at 90 days. These differences were most pronounced for the subset of critical access hospitals that serve remote, rural areas.

CONCLUSIONS: Clinical, public health, and policy efforts are needed to improve rural-urban gaps in care and outcomes for acute cardiovascular conditions.

This comparative effectiveness research study uses Medicare claims data to examine the total number of days at home among intermediate-risk patients recovering from transcatheter aortic valve replacement (TAVR) vs patients recovering from surgical aortic valve replacement (SAVR).

BACKGROUND: People who have been incarcerated have high rates of cardiovascular risk factors, such as hypertension and smoking, and cardiovascular disease (CVD) is a leading cause of hospitalizations and mortality in this population. Despite this, little is known regarding what pathways mediate the association between incarceration exposure and increased rates of CVD morbidity and especially what incarceration specific factors are associated with this risk. The objective of this study is to better understand CVD risk in people exposed to incarceration and the pathways by which accumulate cardiovascular risk over time.

METHODS AND ANALYSIS: The Justice-Involved Individuals Cardiovascular Disease Epidemiology (JUSTICE) study is a prospective cohort study of individuals released from incarceration with known cardiovascular risk factors. We are recruiting 500 individuals within three months after release from jail/prison. At baseline we are assessing traditional risk factors for CVD, including diet, exercise, and smoking, and exposure to incarceration-related policies, psychosocial stress, and self-efficacy. Cardiovascular risk factors are measured at baseline through point of care testing. We are following these individuals for the 12 months following the index release from incarceration with re-evaluation of psychosocial factors and clinical risk factors every 6 months. Using these data, we will estimate the direct and indirect latent effects of incarceration on cardiovascular risk factors and the paths via which these effects are mediated. We will also model the anticipated 10-year burden of CVD incidence, health care use, and mortality associated with incarceration.

DISCUSSION: Our study will identify factors associated with CVD risk factor control among people released from incarceration. Our measurement of incarceration-related exposures, psychosocial factors, and clinical measures of cardiovascular risk will allow for identification of unique targets for intervention to modify CVD risk in this vulnerable population.

BACKGROUND: Cardiovascular disease remains the number one cause of death globally. Patients with cardiovascular disease are at risk of poor outcomes from deferral of healthcare during the coronavirus disease 2019 (COVID-19) pandemic. Little is known about recovery of cardiovascular hospitalizations or procedural volume following the COVID-19 surges. We sought to examine the cardiovascular diagnoses requiring healthcare utilization surrounding the first and second COVID-19 waves and characterize trends in return to pre-pandemic levels at a tertiary care center in Massachusetts.

MATERIALS AND METHODS: Using electronic health records and administrative claims data, we performed a retrospective analysis of patients undergoing cardiovascular procedures and admitted to inpatient cardiology services throughout the first two COVID surges. ICD-10 codes were used to categorize admissions.

RESULTS: Patients who presented for care during the initial COVID-19 surge were younger, had higher comorbidity burden, and longer length-of-stay compared with pre- and post-surge. Marked declines in admissions in the first wave (to 29% of pre-surge levels) followed eventually by complete recovery were noted across all cardiac diagnoses, with smaller declines seen in the second wave. Cardiac procedural volume declined significantly during the initial surge but quickly rebounded post-surge, eventually eclipsing pre-COVID volume.

CONCLUSIONS: There was a gradual but initially incomplete recovery to pre-surge levels of hospitalizations and procedures during the reopening phase, which eventually rebounded to meet or exceed pre-COVID-19 levels. To the extent that this reflects deferred or foregone essential care, it may adversely affect long-term cardiovascular outcomes. These results should inform planning for cardiovascular care delivery during future pandemic surges.

BACKGROUND: Use of an antibiotic-eluting envelope (AEE) during cardiac implantable electronic device procedures reduces infection risk but increases procedural costs. We aim to estimate the cost-effectiveness of AEE use during cardiac implantable electronic device procedures among patients with heart failure.

METHODS: A state-transition cohort model of heart failure patients undergoing cardiac implantable electronic device implantation or generator replacement was developed with input parameters estimated from randomized trials, registries, surveys, and claims data. Effectiveness was estimated from the World-Wide Randomized Antibiotic Envelope Infection Prevention Trial. AEE was assumed to cost $953 per unit. The model projected mortality, quality-adjusted life-years, costs, and the incremental cost-effectiveness ratio of AEE use compared with usual care from a US healthcare sector perspective over a lifetime horizon. We assumed a cost-effectiveness threshold of $100 000 per quality-adjusted life-year gained.

RESULTS: Compared with usual care, AEE use in initial implantations produced an incremental cost-effectiveness ratio of $112 000 per quality-adjusted life-year gained (39% probability of being cost-effective). In generator replacement procedures, AEE use produced an incremental cost-effectiveness ratio of $54 000 per quality-adjusted life-year gained (84% probability of being cost-effective). Results were sensitive to the underlying rate of infection, cost of the AEE, and durability of AEE effectiveness.

CONCLUSIONS: Universal AEE use for cardiac implantable electronic device procedures in patients with heart failure with reduced ejection fraction is unlikely to be cost-effective, reinforcing the need for individualized risk assessment to guide uptake of the AEE in clinical practice. Selective use in patients at increased risk of infection, such as those undergoing generator replacement procedures, is more likely to meet health system value benchmarks.

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.

BACKGROUND: Despite improvements in the safety of transcatheter aortic valve implantation (TAVI),  4% of patients experience a procedure-related stroke. Understanding long-term health and healthcare implications of these events may motivate the development and adoption of preventative strategies.  Aims: We aimed to assess the association of TAVI-related ischaemic stroke with subsequent clinical outcomes and healthcare utilisation.

METHODS: We used Medicare fee-for-service claims to identify patients who underwent their first TAVI between January 2012 and December 2017. Previously used ICD-9-CM and ICD-10-CM codes were used to identify TAVI-related ischaemic stroke. Among those with and without TAVI-related ischaemic stroke, we compared the risk of a composite endpoint that included all-cause mortality, acute myocardial infarction, and subsequent stroke using inverse probability treatment weighted Cox regression. We also performed a difference-in-difference analysis to compare 1-year Medicare expenditures and days spent at home during the first year after TAVI.

RESULTS:  Among 129,628 primary TAVI patients, 5,549 (4.3%) had a procedure-related stroke. These patients were more likely to be female and have had prior stroke, peripheral vascular disease, ischaemic heart disease, or renal failure. After adjustment, TAVI-related ischaemic stroke was associated with a higher risk of the 1-year composite outcome (HR 1.67, 95% CI: 1.56-1.78), higher 1-year Medicare expenditures (difference $9,245 [standard error 790], p<0.001), and fewer days at home during the first year (difference 16 days [standard error 1], p<0.001).

CONCLUSIONS: Among Medicare beneficiaries undergoing TAVI, procedure-related ischaemic stroke was associated with worse outcomes, increased Medicare expenditures, and less time spent at home. Procedure-related ischaemic stroke during TAVI remains a critically important and potentially preventable source of patient mortality, morbidity and healthcare utilisation.

Background Heterozygous familial hypercholesterolemia (FH) is a common genetic disorder causing premature cardiovascular disease. Despite this, there is no national screening program in the United States to identify individuals with FH or likely pathogenic FH genetic variants. Methods and Results The clinical characteristics and FH variant status of 49 738 UK Biobank participants were used to develop a regression model to predict the probability of having any FH variants. The regression model and modified Dutch Lipid Clinic Network criteria were applied to 39 790 adult participants (aged ≥20 years) in the National Health and Nutrition Examination Survey to estimate the yield of FH screening programs using Dutch Lipid Clinic Network clinical criteria alone (excluding genetic variant status), genetic testing alone, or combining clinical criteria with genetic testing. The regression model accurately predicted FH variant status in UK Biobank participants (observed prevalence, 0.27%; predicted, 0.26%; area under the receiver-operator characteristic curve, 0.88). In the National Health and Nutrition Examination Survey, the estimated yield per 1000 individuals screened (95% CI) was 3.7 (3.0-4.6) FH cases with the Dutch Lipid Clinic Network clinical criteria alone, 3.8 (2.7-5.1) cases with genetic testing alone, and 6.6 (5.3-8.0) cases by combining clinical criteria with genetic testing. In young adults aged 20 to 39 years, using clinical criteria alone was estimated to yield 1.3 (95% CI, 0.6-2.5) FH cases per 1000 individuals screened, which was estimated to increase to 4.2 (95% CI, 2.6-6.4) FH cases when combining clinical criteria with genetic testing. Conclusions Screening for FH using a combination of clinical criteria with genetic testing may increase identification and the opportunity for early treatment of individuals with FH.

BACKGROUND: The COVID-19 pandemic has disproportionately affected low-income and racial/ethnic minority populations in the United States. However, it is unknown whether hospitalized patients with COVID-19 from socially vulnerable communities experience higher rates of death and/or major adverse cardiovascular events (MACEs). Thus, we evaluated the association between county-level social vulnerability and in-hospital mortality and MACE in a national cohort of hospitalized COVID-19 patients.

METHODS: Our study population included patients with COVID-19 in the American Heart Association COVID-19 Cardiovascular Disease Registry across 107 US hospitals between January 14, 2020 to November 30, 2020. The Social Vulnerability Index (SVI), a composite measure of community vulnerability developed by Centers for Disease Control and Prevention, was used to classify the county-level social vulnerability of patients' place of residence. We fit a hierarchical logistic regression model with hospital-level random intercepts to evaluate the association of SVI with in-hospital mortality and MACE.

RESULTS: Among 16 939 hospitalized COVID-19 patients in the registry, 5065 (29.9%) resided in the most vulnerable communities (highest national quartile of SVI). Compared with those in the lowest quartile of SVI, patients in the highest quartile were younger (age 60.2 versus 62.3 years) and more likely to be Black adults (36.7% versus 12.2%) and Medicaid-insured (31.1% versus 23.0%). After adjustment for demographics (age, sex, race/ethnicity) and insurance status, the highest quartile of SVI (compared with the lowest) was associated with higher likelihood of in-hospital mortality (OR, 1.25 [1.03-1.53]; P=0.03) and MACE (OR, 1.26 [95% CI, 1.05-1.50]; P=0.01). These findings were not attenuated after accounting for clinical comorbidities and acuity of illness on admission.

CONCLUSIONS: Patients hospitalized with COVID-19 residing in more socially vulnerable communities experienced higher rates of in-hospital mortality and MACE, independent of race, ethnicity, and several clinical factors. Clinical and health system strategies are needed to improve health outcomes for socially vulnerable patients.