Whether thrombocytopenia substantively increases the risk of hemorrhage associated with anticoagulation in patients with atrial fibrillation (AF) is not established. The purpose of this study was to compare rates of bleeding in patients with AF and thrombocytopenia (platelet count < 100 000/μL) to patients with AF and normal platelet counts (>150 000/μL). We performed a propensity score-matched, retrospective cohort study of adults (n = 1070) with a new diagnosis of AF who received a prescription for an oral anticoagulant between 2015 and 2020. The thrombocytopenia cohort was defined as having at least 2 platelet counts <100 000/μL on separate days in the period spanning the 12 weeks preceding the initiation of anticoagulation to 6 weeks after the initiation of anticoagulation. The primary end point was the 1-year cumulative incidence of major bleeding; secondary end points included clinically relevant bleeding, arterial and venous thrombotic events, and all-cause mortality. Patients with AF and thrombocytopenia experienced a higher 1-year cumulative incidence of major bleeding (13.3% vs 5.7%; P < .0001) and clinically relevant bleeding (24.5% vs 16.7%; P = .005) than the controls. Thrombocytopenia was identified as an independent risk factor for major bleeding (hazard ratio, 2.20; confidence interval, 1.36-3.58; P = .001), with increasing risk based on the severity of thrombocytopenia. The cumulative incidence of arterial thrombosis at 1 year was 3.6% in the group with thrombocytopenia and 1.5% in controls (Gray test, P = .08). These findings suggest that baseline platelet counts are an important biomarker for hemorrhagic outcomes in AF and that the degree of thrombocytopenia is an important factor in determining the level of risk.
Publications
2023
BACKGROUND: Days at home (DAH) represents an important patient-oriented outcome that quantifies time spent at home after a medical event; however, this outcome has not been fully evaluated for low-surgical-risk patients undergoing transcatheter aortic valve replacement (TAVR). We sought to compare 1- and 2-year DAH (DAH365 and DAH730) among low-risk patients participating in a randomized trial of TAVR with a self-expanding bioprosthesis versus surgical aortic valve replacement (SAVR).
METHODS: Using Medicare-linked data from the Evolut Low Risk trial, we identified 619 patients: 606 (322 TAVR/284 SAVR) and 593 (312 TAVR/281 SAVR) were analyzed at 1 and 2 years, respectively. DAH was calculated as days alive and spent outside a hospital, inpatient rehabilitation, skilled nursing facility, long-term acute care hospital, emergency department, or observation stay. Mean DAH was compared using the t test.
RESULTS: The mean (SD) age and female sex were 74.7 (5.1) and 74.3 (4.9) years and 34.6% (115/332) and 30.3% (87/287) in TAVR and SAVR, respectively. Postprocedural discharge to rehabilitation occurred in ≤3.0% (≤10/332) in TAVR and 4.5% (13/287) in SAVR. The mean DAH365 was comparable in TAVR versus SAVR (352.2±45.4 versus 347.8±39.0; difference in days, 4.5 [95% CI, 2.3-11.2]; P=0.20). DAH730 was also comparable in TAVR versus SAVR (701.6±106.0 versus 699.6±94.5; difference in days, 2.0 [-14.1 to 18.2]; P=0.81). Secondary outcomes DAH30 and DAH90 were higher in TAVR (DAH30, 26.0±3.6 versus 20.7±6.4; difference in days, 5.3 [4.5-6.2]; P<0.001; DAH90, 85.1±8.3 versus 78.7±13.6; difference in days, 6.4 [4.6-8.2]; P<0.001).
CONCLUSIONS: In the Evolut Low Risk trial linked to Medicare, low-risk patients undergoing TAVR spend a similar number of days at home at 1 and 2 years compared with SAVR. Days spent at home at 30 and 90 days were higher in TAVR. In contrast to higher-risk patients studied in prior work, there is no clear advantage of TAVR versus SAVR for DAH in the first 2 years after AVR in low-surgical-risk patients.
BACKGROUND: The 2017 American College of Cardiology (ACC)/American Heart Association (AHA) guidelines newly classified 31 million US adults as having stage 1 hypertension. The ACC/AHA guidelines recommend behavioral change without pharmacology for the low-risk portion of this group. However, the nationwide reduction in cardiovascular disease (CVD) and associated healthcare expenditures achievable by evidence-based dietary improvements, sustained weight loss, adequate physical activity, and alcohol moderation remain unquantified. We estimated the effect of systolic BP (SBP) control and behavioral changes on 10-year CVD outcomes and costs.
METHODS: We used the CVD Policy Model to simulate CVD events, mortality, and healthcare costs among US adults aged 35-64. We simulated interventions on a target population, identified from the 2015-2018 National Health and Nutrition Examination Survey, with low-risk stage 1 systolic hypertension: defined as untreated SBP 130-139 mmHg and diastolic BP <90 mmHg; no history of CVD, diabetes, or chronic kidney disease; and low 10-year risk of CVD. We used published meta-analyses and trials to estimate the effects of behavior modification on SBP. We assessed the extent to which intermittent healthcare utilization or partial uptake of nonpharmacologic therapy would decrease CVD events prevented.
RESULTS: Controlling SBP to <130 mmHg among the estimated 8.8 million U.S. adults (51% women) in the target population could prevent 26,100 CVD events, avoid 2,900 deaths, and save $1.6 billion in healthcare costs over 10 years. The Dietary Approaches to Stop Hypertension (DASH) diet could prevent 16,000 CVD events among men and 12,000 among women over a decade. Other nonpharmacologic interventions could avert between 3,700 and 19,500 CVD events. However, only 5.5 million (61%) of the target population regularly utilized healthcare where recommended clinician counseling could occur.
CONCLUSIONS: As only two-thirds of U.S. adults with Stage 1 hypertension regularly receive medical care, substantial benefits to cardiovascular health and associated costs may only stem from policies that promote widespread adoption and sustained adherence of nonpharmacologic therapy. Future work should quantify the population-level costs, benefits, and efficacy of improving the food system and local infrastructure on health behavior change.
2022
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: 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.
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: 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: 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: 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.