Publications

BACKGROUND: Microplastics are emerging as environmental pollutants with potential neurotoxic effects, yet their association with neurological disabilities remains largely unexplored.

METHODS: In this cross-sectional study comprising 218 coastal counties in the United States, we compared the self-reported prevalence of cognitive disability, mobility disability, self-care disability, and independent living disability in counties with very high and low marine microplastic levels (MMLs). Unadjusted and adjusted prevalence ratios (PRs) were computed using population-weighted quasi-Poisson regression across three different models to examine the relationship between disability prevalence and MMLs.

RESULTS: Counties exposed to very high marine microplastic levels had a higher mean prevalence of self-reported cognitive disability (15.2% vs. 13.9%), mobility disability (14.1% vs. 12.3%), self-care disability (4.2% vs. 3.6%), and independent living disability (8.5% vs. 7.7%) compared to those exposed to low levels (p < 0.001). Regression analyses revealed significantly elevated adjusted prevalence ratios (PRs) for cognitive (PR: 1.09 [95% CI: 1.06-1.12], p < 0.001), mobility (PR: 1.06 [1.03-1.10], p < 0.001), self-care (PR: 1.16 [1.11-1.20], p < 0.001), and independent living disability (PR: 1.08 [1.05-1.12], p < 0.001) in counties with very high microplastic exposure compared to those with low exposure.

CONCLUSIONS: This study highlights a significant association between marine microplastic pollution and the self-reported prevalence of cognitive, mobility, self-care, and independent living disabilities at the county level. While merely associative, these findings emphasize the urgent need for further investigation into the individual-level health impacts of microplastic exposure and underscore the importance of environmental interventions to mitigate potential risks.

IMPORTANCE: Although Medicare provides nearly universal health insurance coverage for individuals aged 65 years or older, clinicians and policymakers have expressed concern about access to and coverage of mental health services in the program. It is unclear how transitioning to Medicare affects adults with psychological distress, who may be particularly vulnerable to changes in mental health services.

OBJECTIVES: To examine the association of Medicare eligibility with use of mental health care, general health care, and acute care services among adults with psychological distress.

DESIGN, SETTING, AND PARTICIPANTS: In this cross-sectional study using the 2009-2019 Medical Expenditure Panel Survey and a regression discontinuity design, health care use among adults aged 59 to 64 years and those aged 66 to 71 years with psychological distress, defined as those who scored 3 or higher on the 2-item Patient Health Questionnaire or 13 or higher on the 6-item Kessler Psychological Distress Scale, was evaluated. Data were analyzed from March 2023 to February 2025.

EXPOSURES: Medicare eligibility at age 65 years.

MAIN OUTCOMES: Mental health care use, including outpatient mental heath visits and psychotropic medication fills, general health care use, and acute care use.

RESULTS: The study population included 3970 adults with psychological distress (mean [SD] age, 64.0 [3.6] years; 59.7% [n = 2370] female). Medicare eligibility at age 65 years was associated with a decrease in outpatient mental health visits with any health care professional (adjusted change of -3.4 percentage points [95% CI, -5.4 to -1.4 percentage points]), no change in mental health visits with psychiatrists (-0.7 percentage points [95% CI, -4.1 to 2.6 percentage points]), and a decrease in psychotropic medication fills (-5.3 percentage points [95% CI, -10.3 to -0.3 percentage points]) among adults with psychological distress. There was no change in general health care use, including all outpatient visits (0.6 percentage points [95% CI, -5.4 to 6.5 percentage points]) and prescription drug use (0.1 percentage points [95% CI, -2.2 to 2.5 percentage points]). In contrast, Medicare eligibility was associated with increases in acute care use, such as inpatient admissions (5.5 percentage points [95% CI, 2.2-8.9 percentage points]) and emergency department visits (8.1 percentage points [95% CI, 3.3-13.0 percentage points]) among adults with psychological distress.

CONCLUSIONS AND RELEVANCE: These findings suggest that Medicare eligibility at age 65 years was associated with decreased use of mental health outpatient services and increased acute care use among adults with psychological distress. These findings highlight the need for policies that address gaps in mental health care in the Medicare program.

Although cardiovascular death rates vary markedly across US states, little is known about whether state-based inequities in the burden of cardiometabolic and lifestyle risk factors have changed over the past decade. We conducted a serial cross-sectional analysis of US adults using the Behavioral Risk Factor Surveillance System (BRFSS) survey, to evaluate changes in the age- and sex-adjusted prevalence of cardiometabolic risk factors (diabetes, hypertension, hyperlipidemia, and obesity) and lifestyle risk factors (binge alcohol drinking, physical inactivity, and cigarette smoking) across US states from 2011 to 2021. The study population included 945,160 adults in 2011 and 2021. The age- and sex-adjusted prevalence of diabetes (10.9% [95% CI, 10.7%, 11.0%] to 12.4% [12.2%, 12.6%]), hypertension (32.4% [32.1%, 32.7%] to 33.7% [33.4%, 34.0%]), and obesity (27.5% [27.2%, 27.7%] to 33.1% [32.8%, 33.5%]) increased from 2011 to 2021, while hyperlipidemia decreased (38.5% [38.2%, 38.8%] to 35.5% [35.2%, 35.9%]). State-based inequities in the prevalence of diabetes, hypertension, and obesity widened over this period. Across lifestyle factors, the prevalence of binge alcohol use (18.3% [18.0%, 18.5%] to 15.4% [15.2%, 15.7%]), physical inactivity (25.7% [25.4%, 27.4%] to 24.0% [23.6%, 23.7%]), and cigarette smoking (20.1% [19.8%, 20.3%] to 13.4% [13.2%, 13.7%]) decreased, while state-based inequities across these factors generally narrowed. In conclusion, the prevalence of hypertension, diabetes mellitus, and obesity increased among US adults from 2011 to 2021 while state-based inequities in the prevalence of these risk factors widened. In contrast, binge alcohol drinking, physical inactivity, and cigarette smoking all declined. Our findings suggest an urgent need for targeted strategies to address widening state-based inequities in cardiometabolic risk factors.

IMPORTANCE: Improving cardiovascular health in rural areas is a national priority in the US. However, little is known about the current state of rural cardiovascular health and the underlying drivers of any rural-urban disparities.

OBJECTIVE: To compare rates of cardiometabolic risk factors and cardiovascular diseases between rural and urban US adults and to evaluate the extent to which health care access, lifestyle factors, and social risk factors contribute to any rural-urban differences.

DESIGN, SETTING, AND PARTICIPANTS: This nationally representative cross-sectional study analyzed data from US adults aged 20 years or older residing in rural vs urban areas using the 2022 National Health Interview Survey. Data were analyzed between August 2024 and February 2025.

EXPOSURE: County-level rurality.

MAIN OUTCOMES AND MEASURES: The primary outcomes were age-standardized rates of cardiometabolic risk factors (hypertension, hyperlipidemia, obesity, and diabetes) and cardiovascular diseases (coronary heart disease [CHD] and stroke).

RESULTS: The study population consisted of 27 172 adults, including 4256 adults (14.0%) residing in rural areas, 14 741 (54.8%) in small or medium metropolitan areas, and 8175 (31.2%) in urban areas. Mean (SD) participant age was 49.1 (17.8) years, and 4399 participants (50.8%) were female. Compared with their urban counterparts, rural adults were more likely to smoke, be insufficiently physically active, and have more social risk factors. Age-standardized rates of cardiometabolic risk factors were significantly higher in rural areas, including hypertension (37.1% vs 30.9%; rate ratio [RR], 1.20; 95% CI, 1.13-1.27), hyperlipidemia (29.3% vs 26.7%; RR, 1.10; 95% CI, 1.03-1.18), obesity (41.1% vs 30.0%; RR, 1.37; 95% CI, 1.27-1.47), and diabetes (11.2% vs 9.8%; RR, 1.15; 95% CI, 1.02-1.29). The same pattern was observed for CHD (6.7% vs 4.3%; RR, 1.58; 95% CI, 1.35-1.85), but no differences were observed for stroke. The magnitude of rural-urban disparities was largest among young adults (aged 20-39 years) for hypertension (RR, 1.44; 95% CI, 1.12-1.86), obesity (RR, 1.54; 95% CI, 1.34-1.77), and diabetes (RR, 2.59; 95% CI, 1.54-4.38). Rural-urban disparities in cardiovascular health were not meaningfully attenuated after adjustment for measures of health care access (insurance coverage, usual source of care, and recent health care utilization) and lifestyle factors (smoking and physical activity). However, accounting for social risk factors (poverty, education level, food insecurity, and home ownership) completely attenuated rural-urban disparities in hypertension (adjusted RR [aRR], 0.99; 95% CI, 0.93-1.06), diabetes (aRR, 1.02; 95% CI, 0.90-1.15), and CHD (aRR, 1.08; 95% CI, 0.91-1.29), but only partially attenuated disparities in obesity (aRR, 1.29; 95% CI, 1.20-1.39).

CONCLUSIONS AND RELEVANCE: This national cross-sectional study found substantial rural-urban disparities in cardiometabolic risk factors and cardiovascular diseases, which were largest among younger adults and almost entirely explained by social risk factors. These findings suggest that efforts to improve socioeconomic conditions in rural communities may be critical to address the rural-urban gap in cardiovascular health.

The study examines effects of the Centers for Medicaid and Medicare Services State Innovation Models (SIM) on capturing social risk factors in adults hospitalized with atherosclerotic cardiovascular disease (ASCVD). Using a difference-in-differences (DID) approach with propensity score weights, the study compared documentation of secondary diagnosis of social determinants of health (SDOH)/social factors using ICD-9 V codes ("SDOH codes") in adults hospitalized with ASCVD as a primary diagnosis (n = 1 485 354). Data were gathered from January 1, 2010, to September 30, 2015, covering the period before and after the SIM implementation in October 2013. From January 2010 to September 2015, SDOH codes were infrequently utilized among adults with ASCVD (0.55%; 95% CI, 0.43%-0.67%). The SDOH codes with ASCVD increased from pre- to postperiod in SIM states (0.56%-0.93%) and comparison states (0.46%-0.56%). State Innovation Models implementation was associated with greater improvement in SDOH codes utilization (adjusted OR 1.30; 95% CI, 1.18-1.43) during ASCVD hospitalizations. The odds of SDOH codes utilization were 86% higher in emergency department admissions (AOR, 1.86; 95% CI, 1.76-1.97) than in routine admissions with ASCVD. Findings were similar when limiting population to older adults (≥65 years) enrolled in Medicare (AOR 1.50; 95% CI, 1.31-1.71), whereas not significant for Medicaid beneficiaries. The study points to challenges for healthcare providers in documenting SDOH in adults with ASCVD.

BACKGROUND: Private equity firms have rapidly acquired U.S. hospitals and increasingly invested in cardiology over the past decade. However, little is known about how private equity acquisition of hospitals affects care and outcomes for patients with heart failure.

OBJECTIVES: The purpose of this study was to evaluate whether clinical care and outcomes changed for patients with heart failure after the acquisition of U.S. hospitals by private equity firms compared with matched control hospitals.

METHODS: This study identified U.S. hospitals acquired by private equity firms and matched control hospitals from 2012 through 2019. A quasiexperimental difference-in-differences analysis was used to evaluate changes in clinical outcomes, the case mix of admissions and transfers, as well as cardiac procedure utilization among Medicare fee-for-service beneficiaries aged 65 years or older with heart failure.

RESULTS: There were 41 private equity-acquired hospitals and 192 matched control hospitals. After private equity acquisition of hospitals, there was no change in 30-day mortality rates (difference-in-differences [DiD] +0.7 percentage points [95% CI: -0.4 to 1.8]) or 30-day hospital revisit rates (DiD -0.2 percentage points [95% CI: -0.9 to 0.5]), despite a significant decrease in the clinical risk of patients with heart failure when compared with those at matched control (nonacquired) hospitals. Overall hospital transfer rates did not change, but Black patients were significantly more likely to be transferred out to another site after private equity acquisition (DiD +7.1 percentage points [95% CI: 0.7-13.4]), a change not observed across other racial groups. In addition, there was a significant increase in cardiac catheterization rates (DiD estimate, +0.7 percentage points [95% CI: 0.1-1.2]) among heart failure patients at private equity-acquired vs control hospitals.

CONCLUSIONS: These findings suggest that private equity acquisitions of U.S. hospitals do not improve outcomes among older adults with heart failure, despite a decrease in the clinical risk of patients admitted to these sites.

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.