Publications

2025

Beschloss, Alexander, Rishi K Wadhera, and Andrew S Oseran. (2025) 2025. “Utilization and Spending on Lipid Lowering Therapies in Medicaid from 2018 to 2022.”. American Heart Journal 290: 153-57. https://doi.org/10.1016/j.ahj.2025.06.012.

BACKGROUND: To determine how utilization and spending on lipid lowering medications in Medicaid changed between 2018 and 2022.

METHODS: Retrospective, cross-sectional study of utilization and spending on 32 lipid lowering drug formulations (18 brand-name, 14 generic) using the Medicaid Spending by Drug Dataset (2018-2022).

RESULTS: The study included over 115 million prescription fills in the Medicaid program. Between 2018 and 2022, annual prescription fills for lipid lowering medications increased 1.2%, from 22.7 million per year to 22.9 million per year, while annual Medicaid spending on these medications increased 13.2%, from $348.3 million to $394.4 million per year. Annual statin utilization remained stable over the study period (20.4 million fills in 2018 compared to 20.3 million fills in 2022), while spending on statins decreased (from $243.9 million to $228.3 million). Conversely, annual prescription fills and spending for PCSK9 inhibitors (7,617 fills and $8.9 million to 121,737 fills and $65.7 million), icosapent ethyl (32,527 fills and $10.2 million to 180,291 fills and $50.2 million), and bempedoic acid (from 494 fills and $215,499 to 4,619 fills and $2.2 million) all increased between 2018 and 2022.

CONCLUSION: Between 2018 and 2022, annual prescription fills for lipid lowering therapies in Medicaid remained stable while spending on these medications increased, driven by increased utilization of PCSK9 inhibitors, icosapent ethyl, and bempedoic acid. As Medicaid budgets face escalating financial pressure-and the burden of cardiovascular disease increases among low-income adults in Medicaid-it is critical that policymakers continue to monitor utilization and spending on existing and novel high-cost medical therapies.

Mosarla, Ramya C, Mohsin Chowdhury, Kim G Smolderen, Carlos Mena-Hurtado, John Spertus, Robert W Yeh, and Eric A Secemsky. (2025) 2025. “Health Status Improvement After Peripheral Vascular Intervention: Insights From the LIBERTY 360 Study.”. The American Journal of Cardiology 243: 22-31. https://doi.org/10.1016/j.amjcard.2025.01.017.

Improving health status is a primary indication for peripheral endovascular intervention (PVI) for symptomatic peripheral arterial disease. The data informing mid- and long-term changes and predictors of health status following PVI are limited. LIBERTY 360, a prospective, nonrandomized, multicenter study evaluated outcomes in patients undergoing PVI. Health status measures were assessed at 30-days, 1 and 3-years using EQ-VAS (0-100,100 best health) and VascuQol-25 (1-7,7 best health), stratified by claudication (Rutherford 2-3), and chronic limb-threatening ischemia (CLTI, Rutherford 4-6). Multivariable regression identified predictors of health status at 1-year. Repeated measures models were constructed based on patients with available data through 3 years. Outcomes including major adverse events, all-cause death, major amputation/death, target vessel/lesion revascularization, and major adverse limb events (MALE)/post-operative death were reported. Claudication (n = 501, 41.6%) had higher baseline VascuQol total scores (4.3 ± 1.3) compared to CLTI (n = 703, 58.4%) (3.8 ± 1.4). The VascuQol total score improved at 30-days with claudication (5.4 ± 1.3, p < 0.0001) and CLTI (4.7 ± 1.4, p < 0.0001). Baseline EQ-VAS was higher with claudication (68.3 ± 19.7) than with CLTI (63.1 ± 20.1). EQ-VAS improved at 30-days with claudication (74.9 ± 17.9, p < 0.0001) and CLTI (68.6 ± 19.2, p-value:<0.0001). Improvements were maintained through 3-years. Baseline health status, history of PVI, and comorbidities predicted health status after PVI. While major adverse events rates were high at 3-years, this was driven by target vessel/lesion revascularization with high rates of freedom from major amputation, all-cause death, and MALE in both groups. In conclusion, PVI is associated with mid- long-term improvements in health status across peripheral arterial disease severity. Baseline characteristics were associated with health status at 1-year and may inform patient selection.

Berg, Frederikke Held, Mats C Højbjerg Lassen, Muthiah Vaduganathan, Gregg C Fonarow, Robert W Yeh, ZhaoNian Zheng, Gunnar H Gislason, Tor Biering-Sørensen, and Rishi K Wadhera. (2025) 2025. “Cardiovascular Hospitalizations Among Older Adults in the US and Denmark.”. JAMA Cardiology 10 (4): 351-58. https://doi.org/10.1001/jamacardio.2024.5303.

IMPORTANCE: Cardiovascular disease is the leading cause of death in the US. However, it remains unclear how the burden of cardiovascular events in the US compares with that of other high-income countries with distinct health care systems like Denmark, both overall and by income.

OBJECTIVE: To compare cardiovascular hospitalization rates (acute myocardial infarction [MI], heart failure [HF], ischemic stroke) and associated outcomes among adults 65 years or older, overall and by income, between the US and Denmark.

DESIGN, SETTING, AND PARTICIPANTS: This population-based cross-sectional study used national data from the US and Denmark from January 1, 2021, to January 1, 2022. The study population included all Medicare beneficiaries 65 years or older in the US and all adults 65 years or older in Denmark.

MAIN OUTCOMES AND MEASURES: The primary outcome was age- and sex-standardized hospitalization rates for MI, HF, and ischemic stroke, as well as 30-day all-cause mortality rates.

RESULTS: The US study population included 58 614 110 adults 65 years or older (mean [SE] age, 74.6 [7.7] years; 32 179 146 female [54.9%]) of whom 1 171 058 (2.0%) were hospitalized for a cardiovascular event. The Danish study population included 1 176 542 adults 65 years or older (mean [SE] age, 75.3 [7.1] years; 634 217 female [53.9%]) of whom 16 305 (1.4%) were hospitalized with a cardiovascular event. The overall age- and sex-standardized cardiovascular hospitalization rate was significantly higher in the US compared with Denmark (risk ratio [RR], 1.50; 95% CI, 1.47-1.52), as were associated 30-day all-cause mortality rates (RR, 1.12; 95% CI, 1.06-1.17). Across conditions, the risk of hospitalization for MI (RR, 1.56; 95% CI, 1.51-1.61) and HF (RR, 2.37; 95% CI, 2.31-2.43) was significantly higher in the US compared with Denmark, whereas hospitalizations for ischemic stroke were lower (RR, 0.90; 95% CI, 0.88-0.93). Overall cardiovascular hospitalization rates in the US were more than 2-fold higher among low-income adults compared with higher-income adults (RR, 2.38; 95% CI, 2.25-2.47), whereas the magnitude of income-based disparities was smaller in Denmark (RR, 1.45; 95% CI, 1.39-1.50).

CONCLUSIONS AND RELEVANCE: In this international cross-sectional study, cardiovascular hospitalization rates were significantly higher in the US compared with Denmark. There were income-based differences in the burden of cardiovascular hospitalizations in both countries, although the magnitude of these disparities was much greater in the US.

Angrist, Joshua D, Carol Gao, Peter Hull, and Robert W Yeh. (2025) 2025. “Instrumental Variables in Randomized Trials.”. NEJM Evidence 4 (4): EVIDctw2400204. https://doi.org/10.1056/EVIDctw2400204.

AbstractMany randomized clinical trials fail to play out as intended: some participants assigned to the treatment group remain untreated, while others assigned to the control group cross over and receive treatment. In such settings, intention-to-treat analyses that compare participants by treatment assignment are diluted by noncompliance, while per-protocol analyses that compare participants by treatment received are contaminated by selection bias. Instrumental variables methods can address both problems. We explain the rationale for instrumental variables estimation in clinical trials and illustrate instrumental variables methods through an analysis of the effect of revascularization on quality of life. We argue that instrumental variables analysis should be central to pragmatic trials of all kinds, strategy trials in particular, and emerging "nudge trials" that encourage specific health-related behaviors in large populations.

Fakhraei, Reza, Yang Song, Dhruv S Kazi, Rishi K Wadhera, James A de Lemos, Sandeep R Das, David A Morrow, et al. (2025) 2025. “Social Vulnerability and Long-Term Cardiovascular Outcomes After COVID-19 Hospitalization: An Analysis of the American Heart Association COVID-19 Registry Linked With Medicare Claims Data.”. Journal of the American Heart Association 14 (7): e038073. https://doi.org/10.1161/JAHA.124.038073.

BACKGROUND: Patients hospitalized with COVID-19 from socioeconomically vulnerable communities are at risk for in-hospital cardiovascular events. However, the association of socioeconomic vulnerability and outcomes after hospitalization is uncertain.

METHODS AND RESULTS: American Heart Association COVID-19 Cardiovascular Disease Registry hospitalizations between March 1, 2020, and June 30, 2022, linked with Medicare fee-for-service claims, were analyzed. We used Centers for Disease Control and Prevention's Social Vulnerability Index to ascertain county-level and Medicare-Medicaid dual eligibility to ascertain patient-level social vulnerability. We evaluated the association between social vulnerability and a composite of myocardial infarction, stroke, heart failure, venous thromboembolism, cardiogenic shock, cardiac arrest, and death, following discharge, using Cox regression models. The study included 8565 patients (mean age 78 years, 50% female, 16% Black, 4% Hispanic, 25% dual eligible, 34% residing in the most vulnerable counties). Patients residing in the most vulnerable counties, and dual eligible patients, were more likely to be female, Black or Hispanic, and have increased comorbidities. A total of 3783 (52%) patients experienced a composite outcome. We found no association between the most vulnerable, compared with least vulnerable, counties and cardiovascular events (hazard ratio [HR], 0.97 [95% CI, 0.87-1.07]). Dual eligibility, compared with nondual eligibility, was associated with increased cardiovascular events (HR, 1.28 [95% CI, 1.19-1.37]), which was attenuated after adjusting for comorbidities (HR, 0.97 [95% CI, 0.89-1.04]).

CONCLUSIONS: Among survivors of COVID-19 hospitalization, patient-level social vulnerability was associated with cardiovascular events, explained by increased comorbidities. County-level social vulnerability was not observed to be a risk for postdischarge events. Findings suggest targeting public health efforts toward dual eligible patients to mitigate poor outcomes.

Caron, Elisa, Christina L Marcaccio, Emily St John, Siling Li, Yang Song, Robert W Yeh, Marc L Schermerhorn, and Eric A Secemsky. (2025) 2025. “Exploring Socioeconomic Disparities in Outcomes and Follow-up After Endovascular Treatment of Abdominal Aortic Aneurysms Among Medicare Beneficiaries.”. Journal of Vascular Surgery. https://doi.org/10.1016/j.jvs.2025.05.051.

OBJECTIVE: Socioeconomic disparities are known to contribute to adverse outcomes after surgery; however, the role of individual wealth and neighborhood environment on both follow-up and outcomes following endovascular aneurysm repair (EVAR) are not well-understood.

METHODS: We included all fee-for-service Medicare beneficiaries aged ≥66 years who underwent infrarenal EVAR with a bifurcated endograft for intact abdominal aortic aneurysm (AAA) from 2011 to 2019. Patients were divided into cohorts using dual enrollment in Medicare/Medicaid (vs Medicare only) as a measure of individual wealth and residence in a distressed community (vs non-distressed community) as a measure of regional wealth (as defined by the Distressed Community Index [DCI]). The primary outcome was the composite of late aneurysm rupture, aortic reintervention, conversion to open repair, or all-cause mortality at 9 years. The cumulative incidence of the primary composite outcome was determined using Kaplan-Meier methods and compared across groups using log-rank tests.

RESULTS: Of 111,381 patients who underwent EVAR, 9991 (9.0%) were dual-enrolled in Medicare/Medicaid, and 22,902 (21%) lived in distressed communities. A higher incidence of the primary outcome was observed in dual-enrolled vs Medicare-only patients (83% vs 72%; hazard ratio [HR], 1.42; 95% confidence interval [CI], 1.38-1.47; P < .01) and in those living in distressed vs non-distressed communities (75% vs 72%; HR, 1.09; 95% CI, 1.06-1.11; P < .01). After adjustment for comorbidities and other disparity measures, the association between dual enrollment or DCI and the primary outcome was attenuated but remained significant (adjusted HR [aHR], 1.19; 95% CI, 1.15-1.23; aHR, 1.03; 95% CI, 1.00,1.05, respectively). When mortality was removed from the primary outcome, the relationships between dual enrollment or DCI and the composite outcome were no longer significant after adjustment (aHR, 1.02; 95% CI, 0.93-1.13; aHR, 0.95; 95% CI, 0.89-1.05). Among EVAR-specific secondary outcomes, rates of 9-year all-cause mortality and late rupture were higher in dual-enrolled vs Medicare-only patients, and mortality rates were higher in distressed vs non-distressed patients. In addition, both dual-enrolled and residents of distressed communities had lower rates of EVAR-related office visits and AAA-related imaging in follow-up and higher rates of emergency department visits.

CONCLUSIONS: Among Medicare beneficiaries who underwent EVAR for AAA, socioeconomically disadvantaged beneficiaries had a higher incidence of the primary composite outcome, driven primarily by higher all-cause mortality. This study highlights the need for interventions targeted at improving access to appropriate disease surveillance and management of comorbidities for patients who are most vulnerable.