Christina Laternser

Background: Little is known about pediatric heart transplant candidates facing waitlist inactivation. We characterized them and assessed the impact of inactivation on waitlist and transplant outcomes. Methods: The Organ Procurement and Transplantation Network database was queried for pediatric heart‐only transplant candidates. Characteristics, waitlist mortality, and 1‐year posttransplant survival between inactivated and non‐inactivated patients were compared. Predicted probability for the composite outcome of waitlist mortality or removal due to clinical deterioration over time was computed. Results: Of 5202 patients, 1716 (33%) were inactivated, mostly due to temporary illness (58%). Reasons for inactivation varied by age but not diagnosis. Inactivated patients had longer waitlist duration (171 [77–391] vs. 62 [21–144], p < 0.001), more congenital heart disease (61.0% vs. 55.2%, p < 0.001), and were more often supported by ventricular assist device (47.9% vs. 32.9%, p < 0.001) and invasive ventilation at listing (19.9% vs. 13.6%, p < 0.001). Inactivated patients were less likely listed Status 1A (56.8% vs. 62.3%, p < 0.001) and less likely under intensive care at transplant (43.9% vs. 50.2%, p < 0.001). Inactivated patients had higher 1‐year waitlist mortality and removal due to clinical deterioration (SHR 4.40 [3.72–5.20], p < 0.001), though this risk decreased with longer inactive time. One‐year posttransplant survival was similar between groups. Conclusions: Waitlist inactivation was strongly associated with 1‐year waitlist mortality and removal due to clinical deterioration. However, this risk decreased with longer inactive time and made no difference in short‐term posttransplant survival. Thus, the prognostic implications of inactivation are dynamic and can inform future donor allocation policy development.

Objective: To quantify persistence and transition dynamics of county obstetric service absence and assess whether birth volume and physician supply add predictive information beyond prior‐year status. Study Setting and Design: National longitudinal county–year panel study (2015–2023). Obstetric service absence was defined using a 2‐year confirmation rule, with contemporaneous status used for the 2015 baseline year to reduce misclassification. We estimated annual conditional transition probabilities (entry and exit) and modeled current‐year absence as a function of prior‐year absence and year fixed effects, with and without contemporaneous birth volume and physician supply. Data Sources and Analytic Sample: All US counties ( N = 3144) observed annually. Obstetric service availability was identified from Centers for Medicare & Medicaid Services Provider of Services files. Residence‐based births, physician supply, and bed capacity were obtained from the Area Health Resources Files. Population denominators for women aged 15–44 were drawn from the American Community Survey. Principal Findings: Obstetric service absence was highly persistent. County prevalence was stable (34.2% in 2015 and 34.2% in 2023). Population exposure declined: the share of women aged 15–44 residing in counties without services decreased from 6.5% to 5.3%, and the share of births to residents of such counties decreased from 6.6% to 5.7%. Annual transitions were rare (entry ≤ 0.4%; exit ≤ 0.9%), and conditional stay probabilities were ≥ 0.991 for both presence and absence. In lagged‐status models, prior‐year absence strongly predicted current absence (0.994); adding birth volume and physician supply did not materially change the estimate (0.993). Conclusions: On policy‐relevant timescales, obstetric service absence behaves as a high‐inertia system state. Rare transitions and dominance of prior status suggest slow adjustment, with implications for closure prevention and targeting support near volume and workforce feasibility thresholds.

Background Counties without maternity services are commonly summarized using county-based prevalence, defined as the share of counties lacking hospital-based inpatient obstetric services. Because counties vary substantially in population size and birth volume, prevalence-based metrics may misrepresent population burden. This study compares county prevalence and population exposure and describes temporal stability in county classification. Methods Descriptive measurement study using a county-year panel of all 102 Illinois counties from 2015–2023. Counties were classified as without maternity services if no hospital reported inpatient obstetric services in a given year using Centers for Medicare & Medicaid Services (CMS) Hospital General Information files. Women of reproductive age (15–44) were obtained from the American Community Survey; resident birth counts from the Area Health Resources Files. Population exposure was defined as the share of women of reproductive age and births in counties without maternity services. Metropolitan status was defined using Rural–Urban Continuum Codes. Results County prevalence was consistently higher than population exposure, with larger divergence in metropolitan counties. In nonmetropolitan counties, prevalence was approximately 46%–48% compared with 24%–27% of women of reproductive age and births. In metropolitan counties, prevalence was approximately 30% while population exposure was approximately 3%, indicating nearly tenfold overstatement when prevalence is interpreted as population burden. Classification changed little over time. Conclusions County prevalence and population exposure capture distinct constructs and should not be interpreted interchangeably. Reliance on prevalence alone may misclassify population burden and misinform maternal health surveillance and resource allocation. Reporting both measures may improve interpretation.

Objectives Access to hospital-based maternity care has declined across the United States, with an increasing number of counties lacking inpatient obstetric services. Prior research emphasizes workforce shortages, rural disadvantage, and hospital financial strain, but less attention has been paid to how birth volume and workforce capacity jointly relate to the presence of inpatient obstetric services. Methods We conducted a cross-sectional, county-level descriptive analysis of all 102 Illinois counties using logistic regression and sensitivity analyses. The primary outcome was county absence of inpatient obstetric services, defined as no hospital within a county reporting inpatient labor and delivery care. Key structural characteristics included annual birth volume and primary care workforce capacity. Results Sixty-six of 102 counties (64.7%) lacked inpatient obstetric services. Service absence was highly concentrated among low-volume counties (< 240 annual births), reaching 93.3%–100% regardless of workforce capacity. After adjustment, low birth volume was associated with substantially higher odds of service absence (OR, 17.6; 95% CI, 2.5–122.2), whereas workforce capacity showed a weaker, imprecise association (OR, 1.6; 95% CI, 0.2–10.4). Maternal Vulnerability Index scores did not differ significantly between counties with and without services. Conclusions for Practice Birth volume showed the strongest association with inpatient obstetric service presence in Illinois, while workforce capacity differentiates service presence mainly among higher-volume counties. Workforce-focused interventions may be most effective where delivery volume remains adequate. In lower-volume counties, regionalized access strategies, potentially combined with payment models that reduce fixed-cost pressure, may better align with local conditions.

Background: Kawasaki disease is an acute childhood vasculitis that may cause coronary artery aneurysms, raising concern for long-term myocardial dysfunction. Exercise stress echocardiography provides a noninvasive assessment of systolic and diastolic reserve, yet data comparing exercise responses in Kawasaki disease patients with contemporary coronary risk stratification are limited. Materials and methods: We retrospectively analysed exercise stress echocardiograms in patients with a history of Kawasaki disease-related coronary artery aneurysm (maximum coronary artery z -score ≥2.5) and age-matched controls without cardiac disease. Two-dimensional echocardiography was performed at rest and during early recovery following a standardised ergometer exercise test. Left ventricular and left atrial strain and mitral inflow velocities were measured. Within-group pre- and post-exercise changes were assessed using paired t -tests. Linear mixed-effects models evaluated differences in the magnitude of exercise-induced change between groups. Results: There were 34 and 27 patients in the Kawasaki disease and control cohorts, respectively. The Kawasaki disease cohort had a mean maximal coronary z -score of 3.8 ± 2.1. Both groups demonstrated significant pre- to post-exercise changes in left ventricular longitudinal strain and mitral A velocity. Additional systolic and diastolic parameter changes were observed within the Kawasaki disease cohort. Mixed-effects modelling revealed no significant differences in the magnitude of exercise-induced change between Kawasaki disease patients and controls. Conclusions: In paediatric patients with a remote history of Kawasaki disease and mild to moderate coronary artery aneurysms, exercise stress echocardiography demonstrated no differences in the magnitude of exercise-induced changes in systolic and diastolic indices compared to controls.

Policy Points: Service gaps align more closely with feasibility‐related inputs (birth volume and workforce capacity) than with vulnerability alone. As a result, vulnerability‐targeted programs may have a limited impact on service distribution unless observed operational conditions also change (payment/readiness support, staffing depth, liability/fixed costs). Equity strategies differ: modify operational conditions where local provision is desired or formalize regional access (transport/referral networks and non‐hospital supports) where local provision is not observed. Context: Geographic gaps in hospital‐based obstetric services are often framed as “maternity care deserts,” emphasizing community vulnerability and motivating targeted investments. This study was conducted to test whether service geography is more closely aligned with an operational feasibility regime: the birth volume and workforce capacity associated with the observed presence of obstetric services. Methods: A national county‐year panel (2015‐2023) was constructed and used to compare vulnerability‐oriented versus feasibility‐oriented explanations for the presence of obstetric services. Feasibility was measured using prior‐year birth volume and physician workforce supply, as well as their interaction (ln[births] × workforce). Logistic regression models were estimated with county‐clustered standard errors, and non‐nested specifications were compared using the Akaike information criterion (AIC) and the Bayesian information criterion. Analyses were also stratified by metropolitan status. Findings: Feasibility‐based specifications were found to substantially outperform vulnerability‐only models (ΔAIC > 10,000). A hybrid specification including feasibility inputs and maternal vulnerability achieved the strongest overall fit, indicating that vulnerability contributes explanatory information conditional on observed feasibility conditions. In nonmetropolitan counties, an increase in the birth volume from the 25th to the 75th percentile was associated with a 41 percentage point increase in the predicted presence of services, compared with 20 percentage points for a corresponding change in the workforce. Conclusions: Obstetric service distribution was found to be most consistent with a hybrid structure in which feasibility‐related inputs aligned more strongly with the presence of services and vulnerability contributed additional explanatory information conditional on those inputs. These findings suggest that vulnerability‐targeted approaches may imply different policy approaches than interventions targeting observed operational conditions. Within settings consistent with observed feasibility conditions, or where operational arrangements are modified, vulnerability gradients can guide where stabilization investments are most needed.

Research on pharmaceutical competition typically characterizes protection regimes using scalar measures such as patent counts, exclusivity duration, or terminal expiration horizons. This paper argues that these measures collapse categorically different institutional mechanisms into a common temporal metric, obscuring how protection regimes govern transitions to generic competition. I introduce a Structural Feasibility Framework that distinguishes between feasibility constraints, which determine whether generic entry is institutionally possible, and modifying constraints, which shape entry dynamics conditional on feasibility. In pharmaceutical markets, regulatory exclusivity functions as a feasibility constraint because the FDA cannot approve competing products during active exclusivity periods, whereas patents shape entry through contingent litigation and adjudication processes. This distinction implies that the institutional architecture governing protection termination should matter independently of aggregate protection duration. Using FDA Orange Book data (U.S. Food and Drug Administration 2025), I show that markets governed by fixed statutory exclusivity boundaries exhibit more compressed post-expiry generic entry timing distributions, whereas patent-mediated environments exhibit greater dispersion and longer right tails. I further show that markets with similar terminal protection horizons may nevertheless differ in internal protection regime geometry, indicating that scalar terminal-duration measures do not fully characterize institutional protection environments. The paper reconceptualizes pharmaceutical protection regimes as structured institutional architectures rather than scalar durations and develops a framework for analyzing how institutional architecture shapes transitions into competition.

Pharmaceutical markets with similar nominal protection lengths often exhibit markedly different transitions to generic competition. This article examines whether the institutional architecture governing protection termination is associated with the timing of generic entry. Using FDA Orange Book data from 1985–2025, I construct ingredient–form/route markets and analyze the duration between recorded protection expiry and first generic approval. Markets previously governed by statutory regulatory exclusivity exhibit faster post-expiry generic approval than markets without exclusivity, whereas denser patent environments are associated with slower transition. Exclusivity markets also display more compressed timing distributions, with approvals clustering more tightly near expiry and exhibiting thinner long-delay tails. These patterns persist within comparable patent environments and across alternative specifications. The findings suggest that the predictability of protection termination may shape competitive dynamics independently of nominal protection length or patent counts.

Background: Fetal and neonatal outcomes and factors increasing mortality risk in fetal truncus arteriosus are not well characterized. We aimed to examine the prenatally encountered cardiac spectrum, define extracardiac and genetic associations, explore clinical outcomes and identify prenatal factors associated with worse outcomes in a contemporary large cohort. Methods: A multicenter retrospective cohort study was conducted via the Fetal Heart Society Research Collaborative including fetal truncus arteriosus cases encountered between January 1, 2010, and September 1, 2021, within 22 North American cardiac centers. Demographic, clinical, anatomic, and functional fetal echocardiographic variables were analyzed for associations with presurgical death (fetal death/neonatal presurgical death/neonatal listing for heart transplantation before initial hospital discharge). Variables were compared between survivors and nonsurvivors with nonparametric tests and univariable logistic regression; a multivariable linear probability model was used for further assessment after adjusting for confounders. Results: Of 378 fetuses diagnosed prenatally, 201 (53.2%) had a genetic abnormality or extracardiac anomaly identified. Pregnancy termination was chosen in 47 (12.4%) pregnancies and palliative care in 13 (3.4%). Of 318 pregnancies with intention to treat, 17 (5.3%) ended in fetal death and 19 (6%) in neonatal presurgical death. In addition to prematurity and low birth weight, truncal valve stenosis (but not regurgitation or anatomic subtype) and ventricular dysfunction were associated with presurgical death. Conclusions: Half of fetuses with truncus arteriosus will have an associated genetic abnormality or extracardiac anomaly. Truncal valve stenosis and ventricular dysfunction, as well as preterm birth and low birth weight, are associated with presurgical death. These data are important for prognostication and prenatal counseling.

Background: Patients born with single ventricle anatomy palliated with the Fontan procedure are at risk of lymphatic complications (LC), including plastic bronchitis, protein losing enteropathy, and ascites. The mechanism of LC, associated risk factors, and impact on end organ dysfunction and mortality are not well understood. Methods: We performed a single‐center, retrospective, cross‐sectional cohort study of patients with Fontan circulation seen at our center between 2009 and 2022. Univariate comparisons were completed comparing those with and without LC. Results: A total of 314 Fontan patients were included with a mean age of 20.2±10.7 years. Of those patients, 83 (26.4%) had at least 1 LC, including ascites (21.4%), protein losing enteropathy (11.8%), and plastic bronchitis (2.9%). Patients with LC were older (23.5±12.6 versus 19.1±9.8 years, P =0.001) and had their Fontan operation at an older age (5.5 with LC versus 4.0 years without LC, P P =0.004), thromboembolism ( P =0.01), and arrhythmia ( P P =0.003). Fontan patients with LC had higher rates of transplantation (25.3% versus 2.2%, P P <0.001). Conclusions: Fontan‐related lymphatic complications develop in 1 out of 4 patients by 20 years of age, and they are associated with older age, renal dysfunction, thromboembolism, and arrhythmia. Patients with LC have higher rates of transplantation and death. Our findings indicate that elevated central venous pressure, rather than systolic cardiac or atrioventricular valve function, is associated with these complications.