The Effects of HMO and Its For-Profit Expansion on the Survival of Specialized Hospital Services

This study examines the effect of HMO and for-profit HMO share on the survival of safety net services and profitable services in hospitals. Using data from 1990-2003 and proportional hazard models, I find that hospitals in high HMO markets started out having lower hazard of shutting down services in 1990-1994 than those in low HMO markets, but their hazard rates increase over time. By 2000-2003, hospitals in high HMO markets ended up with higher risk of shutting down profitable services than those in low HMO markets. Conditional on overall HMO penetration, markets with higher for-profit share of HMOs have higher hazard of shutting down services, and the gap in survival between high and low for-profit HMO markets is bigger in high HMO areas. Lastly, I find that the hazard rate of shutting down profitable services is comparable among not-for-profit, for-profit, and government hospitals, while the hazard of shutting down safety net services is the highest in for-profit hospitals and lowest in government hospitals.

Surface and Edge States in Topological Semi-metals

We study the topologically non-trivial semi-metals by means of the 6-band Kane model. Existence of surface states is explicitly demonstrated by calculating the LDOS on the material surface. In the strain free condition, surface states are divided into two parts in the energy spectrum, one part is in the direct gap, the other part including the crossing point of surface state Dirac cone is submerged in the valence band. We also show how uni-axial strain induces an insulating band gap and raises the crossing point from the valence band into the band gap, making the system a true topological insulator. We predict existence of helical edge states and spin Hall effect in the thin film topological semi-metals, which could be tested with future experiment. Disorder is found to significantly enhance the spin Hall effect in the valence band of the thin films

Differential benefits of cardiac care regionalization based on driving time to percutaneous coronary intervention

17 USC 105 interim-entered record; under review.The article of record as published may be found at http://dx.doi.org/10.1111/acem.14195Background. Patients with ST-elevation myocardial infarction (STEMI) require timely reperfusion, and percutaneous coronary intervention (PCI) decreases morbidity and mortality. Regionalization of STEMI care has increased timeliness and use of PCI, but it is unknown whether benefits to regionalization depend on a community's distance from its nearest PCI center. We sought to determine whether STEMI regionalization benefits, measured by access to PCI centers, timeliness of treatment (same-day or in-hospital PCI), and mortality, differ by baseline distance to nearest PCI center. Methods. Using a difference-in-difference-in-differences model, we examined access to PCI-capable hospitals, receipt of PCI either on the day of admission or during the care episode, and health outcomes for patients hospitalized from January 1, 2006, to September 30, 2015. Results. Of 139,408 patients (2006 to 2015), 51% could reach the nearest PCI center in <30 minutes, and 49% required ≥30 minutes driving time. For communities with baseline access ≥30 minutes, regionalization increased the probability of admission to a PCI-capable hospital by 9.4% and also increased the likelihood of receiving same-day PCI (by 11.2%) and PCI during the hospitalization (by 7.4%). Patients living within 30 minutes did not accrue significant benefits (measured by admission to a PCI-capable hospital or receipt of PCI) from regionalization initiatives. Regionalization more than halved access disparities and completely eliminated treatment disparities between communities ≥30 minutes and communities <30 minutes from the nearest PCI hospital. Conclusions. Measured by likelihood of admission to a PCI-capable facility and receipt of PCI, benefits of STEMI regionalization in California accrued only to patients whose nearest PCI center was ≥30 minutes away. We found no mortality benefits of regionalization based on distance from PCI center. Our results suggest that policymakers focus STEMI regionalization efforts in communities that are not already well serviced by PCI-capable hospitals

Association Between Emergency Department Closure and Treatment, Access, and Health Outcomes Among Patients With Acute Myocardial Infarction

The article of record as published may be found at https://doi.org/10.1161/CIRCULATIONAHA.116.025057Within the past 2 decades, the annual number of emergency department (ED) visits increased >40%, but the number of EDs decreased by 11%.1 The closure of an ED can have a profound effect on a community,2–5 because patients have to drive farther to obtain care, and the remaining EDs have to bear the extra patient volume, especially for patients experiencing time-sensitive illnesses requiring prompt intervention, such as acute myocardial infarction.This research was supported by the National Heart, Lung, and Blood Institute of the National Institutes of Health under Grant Award Number R01HL114822, and by the American Heart Association under Grant Award Number 13CRP14660029

Emergency Department Closures And Openings: Spillover Effects On Patient Outcomes In Bystander Hospitals

The article of record as published may be found at http://dx.doi.org/10.1377/hlthaff.2019.00125High-occupancy hospitals may be sensitive to neighboring emergency department (ED) closures and openings, as they already operate at or near capacity. We conducted a retrospective analysis using data for the period 2001-13 to examine outcomes of and treatment received by patients with acute myocardial infarction at so-called bystander EDs that had been exposed to nearby ED closures or openings. We used changes in driving time between an ED and the next-closest one as a proxy for a closure or opening: If driving time increased, for instance, it meant that a nearby ED had closed. When a high-occupancy ED was exposed to a closure that resulted in increased driving time of thirty minutes or more to the next-closest ED, one-year mortality and thirty-day readmission rates increased by 2.39 and 2.00 percentage points, respectively, while the likelihood of receiving percutaneous coronary intervention (PCI) declined by 2.06 percentage points. Exposure to ED openings that resulted in decreased driving times of thirty minutes or more was associated with reductions in thirty-day mortality at bystander hospitals and an increased likelihood of receiving PCI. Our findings suggest that limited resources at high-occupancy bystander hospitals make them sensitive to changes in the availability of emergency care in neighboring communities.This work was supported by the National Heart, Lung, and Blood Institute of the National Institutes of Health (Grant Nos. R01HL114822 and R01HL134182 to both Renee Hsia and Yu-Chu Shen).This work was supported by the National Heart, Lung, and Blood Institute of the National Institutes of Health (Grant Nos. R01HL114822 and R01HL134182 to both Renee Hsia and Yu-Chu Shen)

For Better or for Worse, But How About a Recession?

In light of the current economic crisis, we estimate hazard models of divorce to determine how state and national unemployment rates affect the likelihood of divorce. With 89,340 observations over the 1978-2006 period for 7633 couples from the 1979 NLSY, we find mixed evidence on whether increases in the unemployment rate lead to overall increases in the likelihood of divorce, which would suggest countercyclical divorce probabilities. However, further analysis reveals that the weak evidence is due to the weak economy increasing the risk of divorce only for couples in years 6 to 10 of marriage. For couples in years 1 to 5 and couples married longer than 10 years, there is no evidence of a pattern between the strength of the economy and divorce probabilities. The estimates are generally stronger in magnitude when using national instead of state unemployment rates.

The Effect of Soft Budget Constraints on Access and Quality in Hospital Care

Given an increasingly complex web of financial pressures on providers, studies have examined how the hospitals' overall financial health affect different aspects of hospital operation. In our study, we analyze this issue focusing on hospital access and quality by introducing an important aspect of the financial incentives, soft budget constraints (SBC), that takes into account both hospital's current and past financial health as well as their expected financial outlook (i.e., whether there is a sponsoring organization to bail them out). We develop a conceptual framework of SBC by considering the resultant incentives on cost control and quality improvement innovations; and examine the effect of SBC on the following aspects of access and quality: safety net service survival and AMI mortality rates. We find that hospitals with softer budget constraints are less likely to shut down safety net services. In addition, hospitals with softer budget constraints appear to have better mortality outcomes, suggesting that the reduced incentive to engage in cost control innovation as the result of SBC outweighs the dampening effect of quality improvement innovation.

Does Decreased Access to Emergency Departments Affect Patient Outcomes? Analysis of AMI Population 1996-2005

We analyze whether decreased emergency department access (measured by increased driving time to the nearest ED) results in adverse patient outcomes or changes in the patient health profile for patients suffering from acute myocardial infarction. Data sources include 100% Medicare Provider Analysis and Review, AHA hospital annual surveys, Medicare hospital cost reports, and longitude and latitude information for 1995-2005. We define four ED access change categories and estimate a zip codes fixed-effects regression models on the following AMI outcomes: time-specific mortality rates, age, and probability of PTCA on the day of admission. We find a small increase in 30-day to 1-year mortality rates among patients in communities that experience 30-minute increases in driving time, we find a substantial increase in long-term mortality rates, a shift to younger ages (suggesting that the older ones die en route) and a higher probability of immediate PTCA. Most of the adverse effects disappear after the initial three-year transition window.

Comparative Effectiveness Research, COURAGE, and Technological Abandonment

When a major study finds that a widely used medical treatment is no better than a less expensive alternative, do physicians stop using it? Policymakers hope that comparative effectiveness research will identify less expensive substitutes for widely-used treatments, but physicians may be reluctant to abandon profitable therapies. We examine the impact of the COURAGE trial, which found that medical therapy is as effective as percutaneous coronary intervention (PCI) for patients with stable angina, on practice patterns. Using hospital discharge data from US community, Veterans Administration, and English hospitals, we detect a moderate decline in PCI volume post-COURAGE. However, many patients with stable angina continue to receive PCI. We do not find differences in PCI volume trends by reimbursement scheme or hospitals’ teaching status, ownership, or degree of vertical integration.

Community and Hospital Factors Associated With Stroke Center Certification in the United States, 2009 to 2017

The article of record as published may be located at https://doi.org/10.1001/jamanetworkopen.2019.7855Objective: To examine hospital characteristics and economic conditions of communities surrounding hospitals with and without stroke centers. Design, Setting, and Participants: This cohort study included all general, short-term, acute hospitals in the continental United States and used merged data from the Joint Commission, Det Norske Veritas, Healthcare Facilities Accreditation Program, state health departments, the Centers for Medicare & Medicaid Services, the American Hospital Association, the Dartmouth Atlas of Health Care, and the US Census Bureau from January 1, 2009, to September 30, 2017, to compare hospital and community characteristics of stroke-certified and non–stroke-certified hospitals and assessed characteristics of early and late adopters of stroke certification. Main Outcomes and Measures: Stroke center certification was the primary outcome. Risk factors were grouped into 3 categories: economic and financial, hospital, and community characteristics. Survival analyses were performed using a Cox proportional hazards regression model. Results The study included 4546 US hospitals. During the study period, 1689 hospitals (37.2%) were stroke certified (961 adopted certification on or before January 1, 2009, 728 afterward). After controlling for other area and hospital characteristics, hospitals in low-income hospital service areas and the lower tertile of profit-margin distribution were less likely to adopt stroke certification (hazard ratio [HR], 0.62; 95% CI, 0.52-0.74 and HR, 0.87; 95% CI, 0.78-0.98, respectively). Urban hospitals had a higher likelihood of stroke certification than rural hospitals (HR, 12.79; 95% CI, 10.64-15.37). Conclusions and Relevance: This study found that stroke centers have proliferated unevenly across geographic localities, where hospitals in high-income hospital service areas and with higher profit margins have a greater likelihood of being stroke certified. These findings suggest that market-driven factors may be associated with stroke center certification