Kosali Simon

Highlights: Black infants were tested for drug exposure at more than twice the rate of White infants. Among those tested, both groups had similar positive rates—approximately 20%. Clinical risk factors explain only 38% of the racial disparity in testing rates. The remaining 61% may reflect differential treatment or unmeasured clinician observations. These findings raise concerns about fairness and trust in clinical decision-making.

Objective: To describe how the characteristics of Medicare Advantage (MA) beneficiaries with end‐stage kidney disease (ESKD) changed after the 21st Century Cures Act expanded MA eligibility, and to document accompanying changes in utilization. Study Setting and Design: The 2021 Cures Act opened MA to previously diagnosed ESKD patients. Prior to 2021, ESKD patients were ineligible for MA unless diagnosed while enrolled. This cross‐sectional descriptive study used 2017–2023 claims to compare enrollee characteristics before and after 2021, using interrupted time‐series analysis of monthly hospitalizations, emergency department visits, and outpatient visits. Data Sources and Analytic Sample: Optum's de‐identified Clinformatics Data Mart Database (2017–2023) provided data on 216,205 MA beneficiaries with ESKD (359,172 beneficiary‐years). Principal Findings: Post‐policy, enrollees were younger, had lower comorbidity burden and lower education attainment, and were more likely to report household incomes below $40,000. Hospitalization rates were lower immediately post‐policy by 0.013 per beneficiary‐month (6% relative decline; 95% CI, −0.022 to −0.003; p < 0.05). ED visits showed no immediate difference but increased over time. Outpatient visits remained largely stable. Conclusions: Expanded MA eligibility was associated with a substantial shift in the ESKD MA case mix toward younger, relatively healthier, and more socioeconomically vulnerable beneficiaries. Utilization changes reflect these compositional differences.

Extreme weather is a recurring source of stress on healthcare delivery, yet health systems remain largely reactive. Unlike an individual medical emergency, which the system absorbs one case at a time, a heat wave, wildfire smoke episode, or storm affects an entire population simultaneously. The resulting surge degrades care for every emergency patient, not only those the weather directly harmed. Primary care that anticipates weather-related risk and intervenes proactively can blunt that surge, but a central barrier to scaling such care is economic rather than clinical. Conventional prevention accounting counts only the benefit to the treated patient, and fee-for-service payment offers primary care practices only limited and poorly matched means to fund anticipatory care. Payment models that reward keeping patients healthy, such as global budgets, can address this, but only if risk adjustment accounts for environmental exposure so that providers serving vulnerable populations are not penalized. To address this, we outline 4 priorities: evaluations that capture system-wide costs; payment that rewards anticipatory care and adjusts for environmental risk; supply-side resilience in primary care, built jointly with public health agencies; and data infrastructure linking exposure to healthcare utilization.

The CI-PIVOT project, a collaboration between Indiana University, Purdue, and Mississippi State, addresses the gap between complex HPC/AI resources and domain researchers by transforming science experts into embedded Cyberinfrastructure Professionals (CIPs). Through an 18-month cohort model, this project establishes a scalable framework for professionalizing the CIP role, providing insights into training that can be generalized across the broader research ecosystem.

Despite major policy and societal changes over two decades, trends in the demographic and health sorting of nursing home residents remain underexplored. This study focuses on sorting by one demographic factor - race - over time between nursing homes and local communities, and within nursing homes, by another demographic factor - age - as well as health status. Racial sorting is measured using the dissimilarity index, including novel measures of Black, Indigenous, and people of color (BIPOC)/white and Hispanic/white comparisons alongside the established Black/white measure. Racial sorting is higher in nursing homes than in the community for Hispanic/white comparisons, whereas for Black/white and BIPOC/white comparisons, community racial sorting exceeds that in nursing homes. Within nursing homes, racial sorting is highest for Black/white comparisons, higher among older than younger residents, and lowest for those with serious mental illness - possibly reflecting payment source heterogeneity among older residents. Over the study period, overall racial sorting decreased, yet increased within age and health subgroups. These findings underscore the need to understand drivers and consequences of multidimensional sorting in long-term care.

We examine how Medicaid expansion under the Affordable Care Act reshaped federal transfer inflows to counties using state Medicaid expansions between 2014 and 2017. We show that the ACA expansion increased federal Medicaid transfers by $361 per capita in expansion counties. Using our estimates, we forecast that non‐expansion counties would gain $554 per capita if they expanded Medicaid. These transfers flow to counties with lower tax capacity and lower gross income. Our findings suggest that Medicaid expansion was a health policy intervention that also functioned as a budgetary mechanism reshaping federal to local transfers and fiscal smoothing across US counties.

Rates of opioid use disorder (OUD) have increased in older adults (age ≥ 50). Medications for OUD (MOUD) treat OUD effectively; however, limited data exist on whether older adults with OUD are provided MOUD. Using 2016-2020 claims data from Medicare beneficiaries with a new episode of OUD, we calculated rates of MOUD initiation (first dispensing within 14 days of index event), engagement (dispensing of a second MOUD within 34 days of initiation), and retention (receiving MOUD consistently over 180 days). Among beneficiaries with qualifying index events (N = 40 336), 17%, 38%, and 45% were ages 20-49, 50-64, and ≥ 65, respectively. Five hundred and three beneficiaries with a qualifying index event (1.3%) initiated MOUD, 461 (1.1%) reached engagement, and 309 (0.8%) were retained. Multivariable logistic regressions showed older age was associated with reduced MOUD initiation (compared with those aged 20-49, adjusted odds ratios [aORs] were 0.79 [95% CI, 0.64-0.98] and 0.36 [95% CI, 0.25-0.51] for ages 50-64 and ≥65, respectively). Reduced MOUD initiation was associated with female sex (aOR = 0.74; 95% CI, 0.61-0.89) and increasing comorbidity score (aOR = 0.76 per 1-point increase; 95% CI, 0.72-0.80). These results suggest that in addition to general efforts to increase uptake of MOUD, age-specific strategies are needed.