Publications

BACKGROUND: After the Centers for Medicare and Medicaid Services modified reimbursement rates for outpatient peripheral vascular intervention in 2008 with the intent of improving access to care, providers began to increasingly perform peripheral vascular interventions in privately owned office-based clinics. Little is known about the characteristics of patients treated in this setting and their long-term outcomes as compared with those treated in hospital-based centers.

METHODS: In this retrospective cohort study, Medicare beneficiaries ≥66 years undergoing outpatient femoropopliteal peripheral vascular interventions in office-based clinics and hospital-based centers from 2015 to 2017 were identified. Sociodemographics, comorbidities, and institutional characteristics were compared across sites. Multivariable Cox proportional hazards models were used to estimate the adjusted associations between practice site location and outcomes. The primary outcome was the composite of major amputation or death analyzed through the end of follow-up.

RESULTS: Among 134 869 patients, 29.9% were treated in office-based clinics and 70.1% in hospital-based centers. Patients treated in office-based clinics were more often Black (16.9% versus 11.9%), dually enrolled in Medicaid (26.3% versus 19.6%), and residents of lower-resourced regions (32.6% versus 25.6%). Over a median follow-up time of 800 days (interquartile range, 531-1119 days), patients treated in office-based clinics had reduced risks of major amputation or death compared with outpatients treated in hospital-based centers (hazard ratio, 0.92 [95% CI, 0.89-0.95]). They also had lower adjusted all-cause mortality (hazard ratio, 0.93 [95% CI, 0.90-0.96]), major lower extremity amputation (hazard ratio, 0.84 [95% CI, 0.79-0.89]), and all-cause hospitalization (hazard ratio, 0.86 [95% CI, 0.84-0.88]). These findings persisted after stratification by critical limb ischemia, race, dual enrollment, and regional socioeconomic status, as well as among operators treating patients in both clinical settings.

CONCLUSIONS: In this large nationwide analysis of Medicare beneficiaries, office-based clinics treated a more socioeconomically disadvantaged population compared with hospital-based centers. Long-term outcomes were comparable between locations. As such, these clinics appear to be selecting lower-risk patients for outpatient peripheral vascular interventions, although there remains the possibility of unmeasured confounding.

AIMS: Although cardiovascular (CV) mortality increased during the COVID-19 pandemic, little is known about how these patterns varied across key subgroups, including age, sex, and race and ethnicity, as well as by specific cause of CV death.

METHODS AND RESULTS: The Centers for Disease Control WONDER database was used to evaluate trends in age-adjusted CV mortality between 1999 and 2020 among US adults aged 18 and older. Overall, there was a 4.6% excess CV mortality in 2020 compared to 2019, which represents an absolute excess of 62 802 deaths. The relative CV mortality increase between 2019 and 2020 was higher for adults under 55 years of age (11.9% relative increase), vs. adults aged 55-74 (7.9% increase), and adults 75 and older (2.2% increase). Hispanic adults experienced a 9.4% increase in CV mortality (7400 excess deaths) vs. 4.3% for non-Hispanic adults (56 760 excess deaths). Black adults experienced the largest % increase in CV mortality at 10.6% (15 477 excess deaths) vs. 3.5% increase (42 907 excess deaths) for White adults. Among individual causes of CV mortality, there was an increase between 2019 and 2020 of 4.3% for ischaemic heart disease (32 293 excess deaths), 15.9% for hypertensive disease (13 800 excess deaths), 4.9% for cerebrovascular disease (11 218 excess deaths), but a decline of 1.4% for heart failure mortality.

CONCLUSION: The first year of the COVID pandemic in the United States was associated with a reversal in prior trends of improved CV mortality. Increases in CV mortality were most pronounced among Black and Hispanic adults.

OBJECTIVE: To examine the effects of Medicare eligibility and enrollment on the use of high-value and low-value care services.

DATA SOURCES/STUDY SETTING: The 2002-2019 Medical Expenditure Panel Survey.

STUDY DESIGN: We employed a regression discontinuity design, which exploits the discontinuity in eligibility for Medicare at age 65 and compares individuals just before and after age 65. Our primary outcomes included the use of high-value care services (eight services) and low-value care services (seven services). To examine the effects of Medicare eligibility, we conducted a regression discontinuity analysis. To examine the effects of Medicare enrollment, we used the discontinuity in the probability of having Medicare coverage around the age eligibility cutoff and conducted an instrumental variable analysis.

DATA COLLECTION/EXTRACTION METHODS: N/A.

PRINCIPAL FINDINGS: Medicare eligibility and enrollment led to statistically significant increases in the use of only two high-value services: cholesterol measurement [2.1 percentage points (95%: 0.4-3.7) (2.2% relative change) and 2.4 percentage points (95%: 0.4-4.4)] and receipt of the influenza vaccine [3.0 percentage points (95%: 0.3-5.6) (6.0% relative change) and 3.6 percentage points (95%: 0.4-6.8)]. Medicare eligibility and enrollment led to statistically significant increases in the use of two low-value services: antibiotics for acute upper respiratory infections [6.9 percentage points (95% CI: 0.8-13.0) (24.0% relative change) and 8.2 percentage points (95% CI: 0.8-15.5)] and radiographs for back pain [4.6 percentage points (95% CI: 0.1-9.2) (36.8% relative change) and 6.2 percentage points (95% CI: 0.1-12.3)]. However, there was no significant change in the use of other high-value and low-value care services.

CONCLUSION: Medicare eligibility and enrollment at age 65 years led to increases in the use of some high-value and low-value care services, but there were no changes in the use of the majority of other services. Policymakers should consider refining the Medicare program to enhance the value of care delivered.

BACKGROUND: Racial and social disparities exist in outcomes related to cancer and cardiovascular disease (CVD).

OBJECTIVES: The aim of this cross-sectional study was to study the impact of social vulnerability on mortality attributed to comorbid cancer and CVD.

METHODS: The Centers for Disease Control and Prevention Wide-Ranging Online Data for Epidemiologic Research database (2015-2019) was used to obtain county-level mortality data attributed to cancer, CVD, and comorbid cancer and CVD. County-level social vulnerability index (SVI) data (2014-2018) were obtained from the CDC's Agency for Toxic Substances and Disease Registry. SVI percentiles were generated for each county and aggregated to form SVI quartiles. Age-adjusted mortality rates (AAMRs) were estimated and compared across SVI quartiles to assess the impact of social vulnerability on mortality related to cancer, CVD, and comorbid cancer and CVD.

RESULTS: The AAMR for comorbid cancer and CVD was 47.75 (95% CI: 47.66-47.85) per 100,000 person-years, with higher mortality in counties with greater social vulnerability. AAMRs for cancer and CVD were also significantly greater in counties with the highest SVIs. However, the proportional increase in mortality between the highest and lowest SVI counties was greater for comorbid cancer and CVD than for either cancer or CVD alone. Adults <45 years of age, women, Asian and Pacific Islanders, and Hispanics had the highest relative increase in comorbid cancer and CVD mortality between the fourth and first SVI quartiles, without significant urban-rural differences.

CONCLUSIONS: Comorbid cancer and CVD mortality increased in counties with higher social vulnerability. Improved education, resource allocation, and targeted public health interventions are needed to address inequities in cardio-oncology.

BACKGROUND: US policymakers are debating whether to expand the Medicare program by lowering the age of eligibility. The goal of this study was to determine the association of Medicare eligibility and enrollment with healthcare access, affordability, and financial strain from medical bills in a contemporary population of low- and higher-income adults in the US.

METHODS AND FINDINGS: We used cross-sectional data from the National Health Interview Survey (2019) to examine the association of Medicare eligibility and enrollment with outcomes by income status using a local randomization-based regression discontinuity approach. After weighting to account for survey sampling, the low-income group consisted of 1,660,188 adults age 64 years and 1,488,875 adults age 66 years, with similar baseline characteristics, including distribution of sex (59.2% versus 59.7% female) and education (10.8% versus 12.5% with bachelor's degree or higher). The higher-income group consisted of 2,110,995 adults age 64 years and 2,167,676 adults age 66 years, with similar distribution of baseline characteristics, including sex (40.0% versus 49.4% female) and education (41.0% versus 41.6%). The share of adults age 64 versus 66 years enrolled in Medicare differed within low-income (27.6% versus 87.8%, p < 0.001) and higher-income groups (8.0% versus 85.9%, p < 0.001). Medicare eligibility at 65 years was associated with a decreases in the percentage of low-income adults who delayed (14.7% to 6.2%; -8.5% [95% CI, -14.7%, -2.4%], P = 0.007) or avoided medical care (15.5% to 5.9%; -9.6% [-15.9%, -3.2%], P = 0.003) due to costs, and a larger decrease in the percentage who were worried about (66.5% to 51.1%; -15.4% [-25.4%, -5.4%], P = 0.003) or had problems (33.9% to 20.6%; -13.3% [-23.0%, -3.6%], P = 0.007) paying medical bills. In contrast, there were no significant associations between Medicare eligibility and measures of cost-related barriers to medication use. For higher-income adults, there was a large decrease in worrying about paying medical bills (40.5% to 27.5%; -13.0% [-21.4%, -4.5%], P = 0.003), a more modest decrease in avoiding medical care due to cost (3.5% to 0.6%; -2.9% [-5.3%, -0.5%], P = 0.02), and no significant association between eligibility and other measures of healthcare access and affordability. All estimates were stronger when examining the association of Medicare enrollment with outcomes for low and higher-income adults. Additional analyses that adjusted for clinical comorbidities and employment status were largely consistent with the main findings, as were analyses stratified by levels of educational attainment. Study limitations include the assumption adults age 64 and 66 would have similar outcomes if both groups were eligible for Medicare or if eligibility were withheld from both.

CONCLUSIONS: Medicare eligibility and enrollment at age 65 years were associated with improvements in healthcare access, affordability, and financial strain in low-income adults and, to a lesser extent, in higher-income adults. Our findings provide evidence that lowering the age of eligibility for Medicare may improve health inequities in the US.

Background The AHA Registry (American Heart Association COVID-19 Cardiovascular Disease Registry) captures detailed information on hospitalized patients with COVID-19. The registry, however, does not capture information on social determinants of health or long-term outcomes. Here we describe the linkage of the AHA Registry with external data sources, including fee-for-service (FFS) Medicare claims, to fill these gaps and assess the representativeness of linked registry patients to the broader Medicare FFS population hospitalized with COVID-19. Methods and Results We linked AHA Registry records of adults ≥65 years from March 2020 to September 2021 with Medicare FFS claims using a deterministic linkage algorithm and with the American Hospital Association Annual Survey, Rural Urban Commuting Area codes, and the Social Vulnerability Index using hospital and geographic identifiers. We compared linked individuals with unlinked FFS beneficiaries hospitalized with COVID-19 to assess the representativeness of the AHA Registry. A total of 10 010 (47.0%) records in the AHA Registry were successfully linked to FFS Medicare claims. Linked and unlinked FFS beneficiaries were similar with respect to mean age (78.1 versus 77.9, absolute standardized difference [ASD] 0.03); female sex (48.3% versus 50.2%, ASD 0.04); Black race (15.1% versus 12.0%, ASD 0.09); dual-eligibility status (26.1% versus 23.2%, ASD 0.07); and comorbidity burden. Linked patients were more likely to live in the northeastern United States (35.7% versus 18.2%, ASD 0.40) and urban/metropolitan areas (83.9% versus 76.8%, ASD 0.18). There were also differences in hospital-level characteristics between cohorts. However, in-hospital outcomes were similar (mortality, 23.3% versus 20.1%, ASD 0.08; home discharge, 45.5% versus 50.7%, ASD 0.10; skilled nursing facility discharge, 24.4% versus 22.2%, ASD 0.05). Conclusions Linkage of the AHA Registry with external data sources such as Medicare FFS claims creates a unique and generalizable resource to evaluate long-term health outcomes after COVID-19 hospitalization.