Abstract 246: Effect of Racial Factors on Timing of Readmissions After Myocardial Infarction

Background: Readmissions following acute myocardial infarction (MI) are associated with increased cost, healthcare utilization, and morbidity. The purpose of this study was to assess racial factors in influencing time for readmission after being admitted with myocardial infarction. Methods: We reviewed 6,626 cases of MI at a single quaternary care medical center from January 1 st , 2010 to January 1 st , 2017 (29% STEMI, 71% NSTEMI), and we identified all readmissions within 90 days after index MI. The patients were categorized according to their race into White Americans (72%), African Americans (25%) and others (3%). Readmissions were stratified into early (0-30 days) and late (31-90 days) time periods depending on the timing of readmission and these readmissions were also separated according to their corresponding race into White Americans (62%), African Americans (35%) and others (3%). Since White Americans and African Americans contributed to the bulk of our patient population, we analyzed the difference between these two groups. Results: There were a total of 2051 readmissions within 90 days after index MI. Overall, 50% of readmissions were in the early time period and 50% in the late period (after 30 days). 46% of African Americans were readmitted in the early time period compared to 52% of white patients whereas 54% of African Americans were readmitted in the late time period compared to 48% of white patients (P=0.0037). Conclusions: The temporal pattern of readmissions after myocardial infarction differed between Whites and African Americans. These findings may have implications regarding the development of readmission reduction strategies.

Survival Advantage to Allogeneic Transplant in Patients with Myelofibrosis with Intermediate-1 or Higher DIPSS Score

Introduction: Allogeneic hematopoietic stem cell transplantation (HCT) is the only curative therapy for myelofibrosis (MF). Consideration of HCT is recommended by international working groups and national guidelines for MF patients (pts) age <70 with intermediate-1 with adverse indicators, intermediate-2 or high-risk disease by the Dynamic International Prognostic Scoring System (DIPSS) for MF- a recommendation made in the absence of clear data indicating the optimal timing of HCT for MF. In this large multicenter retrospective study, we analyze overall survival in MF pts treated with and without HCT. Methods: Disease characteristics, treatments, and outcome data from MF pts receiving non-transplant therapy at 14 US academic medical centers between 2000-2014 were retrospectively collected. MF pts who underwent HCT were identified from the Center for International Blood and Marrow Transplant Research (CIBMTR). The Cox proportional hazards model was used. The reference time point (time zero) was time of referral for the non-transplant (non-HCT) arm and the time of transplant for the HCT arm. The main effect variable (HCT vs. non-HCT) violated the proportionality assumption where comparing to non-HCT, mortality was higher with HCT in early time period from time zero but then was lower in late time period; therefore, the comparison is presented as early time period and late time period. The Cox model identified 14 months from time zero as the ideal cut point to define early and late time periods. The proportionality assumption is satisfied within each of these two periods. Results: A total of 1377 and 551 pts were included in the non-HCT and HCT arms, respectively (Table 1). In the overall cohort, survival was higher with non-HCT vs. HCT in early time period (relative risk [RR]: 0.34, P< .0001, Figure 1D), but in late time period survival was lower with non-HCT vs. HCT (RR: 2.37, P< 0.001) (Table 2). In the DIPSS low-risk MF group, while survival was higher with non-HCT vs. HCT in the early time period (RR: 0.19, P=0.007, Figure 1A), survival was lower with non-HCT in the late time period, but the latter did not reach statistical significance (RR: 1.45, P=0.39). In the DIPSS intermediate-1 risk group, a survival advantage was present with non-HCT treatments vs. HCT in the early time period (RR: 0.27, P < .0001, Figure 1B), however survival was lower with non-HCT in the late time period (RR: 3.13, P < .0001). Similarly, in those with DIPSS intermediate-2 and high-risk MF, survival advantage was observed with non-HCT in the early time period (RR: 0.41, P< .0001, Figure IC), but survival was lower with non-HCT in the late time period (RR: 2.82, P < .0001). Conclusion: A long-term survival advantage with transplant was observed for pts with intermediate-1 or higher risk MF, but at the cost of potential early mortality. The magnitude of benefit increased as DIPSS risk score increased. Although this retrospective study has limitations, the results have an impact on clinical practice by suggesting that transplantation could be considered earlier in the disease course and supports the recommendation for consideration of HCT in the setting of intermediate-1 risk MF. Disclosures Gowin: Incyte: Consultancy, Other: Scientific Advisory Board, Speakers Bureau. Verstovsek:Celgene: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Incyte: Consultancy; Italfarmaco: Membership on an entity's Board of Directors or advisory committees. Ali:Incyte Corporation: Membership on an entity's Board of Directors or advisory committees. Gupta:Novartis: Consultancy, Honoraria, Research Funding; Incyte: Research Funding. Gerds:Celgene: Consultancy; Apexx Oncology: Consultancy; CTI Biopharma: Consultancy; Incyte: Consultancy.

Cost Implications of Comorbidity for Autologous Stem Cell Transplantation in Elderly Patients with Multiple Myeloma Using SEER-Medicare

Comorbidity is more common in older patients and can increase the cost of care by increasing toxicity. Using the SEER-Medicare database from 2000 to 2007, we examined the costs and life-year benefit of Auto-HSCT for MM patients over the age of 65 by evaluating the difference over time relative to comorbidity burden. One hundred ten patients had an Auto-HSCT in the early time period (2000–2003) and 160 in the late time period (2004–2007). Patients were divided by a Charlson Comorbidity Index (CCI) of 0 or greater than 1 (CCI1+). Median overall survival was 53.5 months for the late time period patients compared to 40.3 months for the early time period patients (p=0.031). Median costs for CCI0 versus CCI1+ in the early period were, respectively, $70,900 versus $72,000 (100 d); $86,100 versus $98,300 (1 yr); and $139,200 versus $195,300 (3 yrs). Median costs for late period were, respectively, $58,400 versus $60,400 (100 d); $86,300 versus $77,700 (1 yr); and $124,400 versus $110,900 (3 yrs). Comorbidity had a significant impact on survival and cost among early time period patients but not among late time period patients. Therefore, older patients with some comorbidities can be considered for Auto-HSCT depending on clinical circumstances.

On the universality of turbulent axisymmetric wakes

Direct numerical simulations (DNS) of two time-dependent, axially homogeneous, axisymmetric turbulent wakes having very different initial conditions are presented in order to assess whether they reach a universal self-similar state as classically hypothesized by Townsend. It is shown that an extensive early-time period exists during which the two wakes are individually self-similar with wake widths growing like$\delta \propto {t}^{1/ 3} $, as predicted by classical dimensional analysis, but have very different growth rates and are thus not universal. Subsequently, however, the turbulence adjusts to yield, eventually, wakes that are structurally identical and have the same growth rate (also with$\delta \propto {t}^{1/ 3} $) so provide clear evidence of a universal, self-similar state. The former non-universal but self-similar state extends, in terms of a spatially equivalent flow behind a spherical body of diameter$d$, to a distance of$O(3000d)$whereas the final universal state does not appear before$O(5000d)$(and exists despite relatively low values of the Reynolds number and no evidence of a spectral${\kappa }^{\ensuremath{-} 5/ 3} $inertial subrange). Universal wake evolution is therefore likely to be rare in practice. Despite its low Reynolds number, the flow does not exhibit the sometime-suggested alternative self-similar behaviour with$\delta \propto {t}^{1/ 2} $(as for the genuinely laminar case) at large times (or, equivalently, distances), since the eddy viscosity remains large compared to the molecular viscosity and its temporal variations are not negligible.

The Effect of Race, Sex, and Insurance Status on Time-to-Listing Decisions for Liver Transplantation

Fair allocation of organs to candidates listed for transplantation is fundamental to organ-donation policies. Processes leading to listing decisions are neither regulated nor understood. We explored whether patient characteristics affected timeliness of listing using population-based data on 144,507 adults hospitalized with liver-related disease in Pennsylvania. We linked hospitalizations to other secondary data and found 3,071 listed for transplants, 1,537 received transplants, and 57,020 died. Among candidates, 61% (n=1,879) and 85.5% (n=2,626) were listed within 1 and 3 years of diagnosis; 26.7% (n=1,130) and 95% (n=1,468) of recipients were transplanted within 1 and 3 years of listing. Using competing-risks models, we found few overall differences by sex, but both black patients and those insured by Medicare and Medicaid (combined) waited longer before being listed. Patients with combined Medicare and Medicaid insurance, as well as those with Medicaid alone, were also more likely to die without ever being listed. Once listed, the time to transplant was slightly longer for women, but it did not differ by race/ethnicity or insurance. The early time period from diagnosis to listing for liver transplantation reveals unwanted variation related to demographics that jeopardizes overall fairness of organ allocation and needs to be further explored.

ANOTHER LOOK AT THE CP VIOLATION PROBLEM

We show that the interpretation of neutral kaon decay (and [Formula: see text] and other decay) experiments is based on a not-too-correct theoretical description of such decays. This description does not take into account the specific early time properties of temporal evolution in the two-component subspace of a state space. The particle interpretation of vectors in such a subspace is shown to be proper for other states in an early time period and other states in a long time period.

Time evolution of the velocity distribution of neutral-beam-injected ions heated by ICRH in a two-component plasma

The time evolution of the distribution function of the beam-injected particles in the presence of ICRH in a two-component plasma is determined. Consideration is restricted to the time development during two complementary time periods: (i) the early time period, i.e. 0 ≤t ≪ TS, and (ii) the quasi-steady state, i.e. t > Ts, where Ts is the slowing-down time for beam-ion-electron collisions. Explicit analytical solutions are obtained for anisotropic as well as isotropie beam injection.

Pulmonary Leukosequestration without Hypoxemia during Hemodialysis

Dialysis-associated hypoxemia is frequently of clinically significant magnitude and is incompletely understood. In order to investigate the hypoxemia directly we labelled a patient's white blood cells with 111Indium-oxine prior to hemodialysis with acetate or bicarbonate baths. Both dialysate buffers were associated with similar degrees of early peripheral neutropenia, complement activation and elevation of lactoferrin levels, with simultaneous lung localization of radionuclide activity. However, there was not widening of the alveolar to arterial oxygen gradient, or increased wasted ventilatory fraction during this early time period. Significant hypoxemia occurred later in the dialysis, was associated with a decreased respiratory exchange ratio and only occurred with the acetate dialysate buffer. Thus, initial pulmonary leukosequestration was documented but did not have an adverse impact on gas exchange. Hypoxemia during acetate dialysis occurred instead as a consequence of alveolar hypoventilation.

Studies on experimental murine histoplasmosis: host protection and cellular immunity

Mice immunized subcutaneously with 106 viable yeast cells of Histoplasma capsulatum exhibited host protection to a challenge infection and also exhibited concomitant manifestations of cellular immunity to a culture filtrate antigen (yeast extract dialysate (YED)-histoplasmin). Protective immunity was determined by quantitative culture of organisms from infected spleens on a solid medium containing a growth factor produced by the organism. As early as 4 days following immunization, host protection was observed in mice. Positive footpad swelling, indicative of delayed-type hypersensitivity, also was apparent at the early time period (4–7 days) after immunization. By days 14 and 21 following immunization, the mice exhibited maximum footpad responses and maximum splenic clearance of yeast cells. As an additional correlate of cellular immunity, YED-histoplasmin was coupled with chromic chloride to murine erythrocytes (M-RBC) and mixed with immune or nonimmune splenic lymphocytes to detect antigen-specific rosette forming cells (RFC's). Only splenic lymphocytes from mice immunized with H. capsulatum formed antigen-specific RFC's (≥ 0.2%). Pretreatment of splenic lymphocytes with antitheta (θ) serum plus complement greatly reduced the numbers of RFC's, illustrating their T cell nature. Host protection and cell-mediated immune responses decreased substantially by day 28 following immunization.

THE ANATOMICAL CHARACTERISTICS OF DOPAMINE-β-HYDROXYLASE ACCUMULATION IN LIGATED SCIATIC NERVE

The anatomical characteristics of the accumulation of dopamine-β-hydroxylase (DBH) that occurs after ligation of rat sciatic nerve were examined in detail using a recently developed specific immunofluorescence method. Although rapid accumulation of DBH occurred showing the presence of axonal transport, the anatomical observations indicated that the build-up was considerably more complex than the simple "blockade" model frequently used as a basis for computation of transport rates from quantitative estimates of accumulation. During the early time period (7 hr) the situation was complicated by a substantial amount of accumulation of DBH distal to the ligation. By 24 hr after ligation the distal accumulation was small compared to that present proximally. The size of the discrete areas covered by DBH fluorescence at 24 hr indicated that axonal membranes may have already started to rupture, thus releasing vesicles into the extracellular space. By 48 hr after ligation the DBH was no longer confined to the area near the ligation, but extended 3.6 mm proximally. By 96 hr after ligation there had been a net loss of DBH fluorescence indicating that degradation and clearance of accumulated DBH had occurred.