Mapping the Ecological Terrain of Stroke Prehospital Delay: A Nationwide Registry Study

BACKGROUND

Delays in hospital presentation limit access to acute stroke treatments. While prior research has focused on patient-level factors, broader ecological and social determinants have not been well studied. We aimed to create a geospatial map of prehospital delay and examine the role of community-level social vulnerability.

METHODS

We studied patients with ischemic stroke who arrived by emergency medical services in 2015 to 2017 from the American Heart Association Get With The Guidelines-Stroke registry. The primary outcome was time to hospital arrival after stroke (in minutes), beginning at last known well in most cases. Using Geographic Information System mapping, we displayed the geography of delay. We then used Cox proportional hazard models to study the relationship between community-level factors and arrival time (adjusted hazard ratios [aHR] <1.0 indicate delay). The primary exposure was the social vulnerability index (SVI), a metric of social vulnerability for every ZIP Code Tabulation Area ranging from 0.0 to 1.0.

RESULTS

Of 750 336 patients, 149 145 met inclusion criteria. The mean age was 73 years, and 51% were female. The median time to hospital arrival was 140 minutes (Q1: 60 minutes, Q3: 458 minutes). The geospatial map revealed that many zones of delay overlapped with socially vulnerable areas (https://harvard-cga.maps.arcgis.com/apps/webappviewer/index.html?id=08f6e885c71b457f83cefc71013bcaa7). Cox models (aHR, 95% CI) confirmed that higher SVI, including quartiles 3 (aHR, 0.96 [95% CI, 0.93-0.98]) and 4 (aHR, 0.93 [95% CI, 0.91-0.95]), was associated with delay. Patients from SVI quartile 4 neighborhoods arrived 15.6 minutes [15-16.2] slower than patients from SVI quartile 1. Specific SVI themes associated with delay were a community's socioeconomic status (aHR, 0.80 [95% CI, 0.74-0.85]) and housing type and transportation (aHR, 0.89 [95% CI, 0.84-0.94]).

CONCLUSIONS

This map of acute stroke presentation times shows areas with a high incidence of delay. Increased social vulnerability characterizes these areas. Such places should be systematically targeted to improve population-level stroke presentation times.

Prevalence and Predictors of Inappropriate Antithrombotic Prescription in Patients Presenting With Traumatic Brain Injury

BACKGROUND AND OBJECTIVES

A growing proportion of the US population is on antithrombotic therapy (AT), most significantly within the older subpopulation. Decision to use AT is a balance between the intended benefits and known bleeding risk, especially after traumatic brain injury (TBI). Preinjury inappropriate AT offers no benefit for the patient and also increases the risk of intracranial hemorrhage and worse outcome in the setting of TBI. Our objective was to examine the prevalence and predictors of inappropriate AT among patients presenting with TBI to a Level-1 Trauma Center.

METHODS

A retrospective chart review was performed on all patients with TBI and preinjury AT who presented to our institution between January 2016 and September 2020. Demographic and clinical data were collected. Appropriateness of AT was determined through established clinical guidelines. Clinical predictors were determined by logistic regression.

RESULTS

Of 141 included patients, 41.8% were female (n = 59) and the average age (mean ± SD) was 80.6 ± 9.9. The prescribed antithrombotic agents included aspirin (25.5%, n = 36), clopidogrel (22.7%, n = 32), warfarin (46.8%, n = 66), dabigatran (2.1%, n = 3), rivaroxaban (Janssen) (10.6%, n = 15), and apixaban (Bristol-Myers Squibb Co.) (18.4%, n = 26). The indications for AT were atrial fibrillation (66.7%, n = 94), venous thromboembolism (13.4%, n = 19), cardiac stent (8.5%, n = 12), and myocardial infarction/residual coronary disease (11.3%, n = 16). Inappropriate antithrombotic therapy use varied significantly by antithrombotic indication ( P < .001) with the highest rates seen with venous thromboembolism. Predictive factors also include age ( P = .005) with higher rates younger than 65 years and older than 85 years and female sex ( P = .049). Race and antithrombotic agent were not significant predictors.

CONCLUSION

Overall, 1 in 10 patients presenting with TBI were found to be on inappropriate AT. Our study is the first to describe this problem and warrants investigation into possible workflow interventions to prevent post-TBI continuation of inappropriate AT.

Personal social networks of people with Down syndrome

Studies in the neurotypical population have demonstrated that personal social networks can mitigate cognitive decline and the development of Alzheimer disease. To assess whether these benefits can also be extended to people with Down syndrome (DS), we studied whether and how personal networks can be measured in this population. We adapted a personal networks instrument previously created, validated, and implemented for the neurotypical population. We created two versions of the survey: one for participants with DS, ages 25 and older, and another for their study partners, who spent a minimum of 10 h/wk in a caregiver role. Participants with DS gave concordant data to those of study partners. Their personal networks included a median network size of 7.50, density 0.80, constraint 46.00, and effective size 3.07. Personal networks were composed of 50% kin, 80% who live within 15 miles, and 80% who eat a healthy diet. In this proof-of-principle study, we demonstrated that the personal networks of people with DS can be quantitatively analyzed, with no statistical difference between self-report and parent-proxy report. Future research efforts can now evaluate interventions to enhance personal networks for preventing Alzheimer disease in this population.

Abstract P133: Geospatial Mapping of Prehospital Delay in Acute Ischemic Stroke and Association With Social Vulnerability

Introduction: Prehospital delay, defined as the delay between symptom discovery and hospital arrival, remains a major barrier to timely acute stroke treatments. Delay is worse in socially vulnerable populations. A geospatial map of prehospital delay may identify high-risk areas and highlight the role of community social vulnerability in delay. We hypothesized that a community’s social vulnerability would be associated with delay.

Methods: We analyzed national Get With The Guidelines ischemic stroke data between 2015 and 2017. We calculated the median arrival time (symptom discovery-to-door times) for each Zip Code Tabulation Area (ZCTA), and created geospatial map using ArcGIS. The primary exposure variable was the Center for Disease Control’s Social Vulnerability Index (SVI), and its 4 subcomponents. The SVI is a composite metric of community vulnerability using U.S. Census data (0, least vulnerable to 1, most vulnerable). To account for clustering within ZCTAs, we performed a multilevel linear regression of community-level SVI and patient-level prehospital delay.

Results: During the study period, 149,774 patients had an ischemic stroke in 16,949 ZCTAs. Across patients, the median time of arrival was 140 mins, IQR was 60-459 mins, and range was 1-1439 mins. Arrival by 2h occurred in 46% of patients. Multilevel regression showed a strong positive association between the SVI and prehospital delay, evident in the maps (Figure). For every 10% increase in the SVI, the arrival time increased by 38 minutes [CI, 30 - 47] (p<0.001). Considering the 4 SVI subcomponents, delay was most strongly associated with socioeconomic status, household composition, and housing/transportation, but not minority status/language.

Conclusion: Using geospatial mapping of prehospital delay across the United States, we show that community SVI is strongly associated with delayed ischemic stroke arrival. These maps help identify communities to target for stroke preparedness campaigns.

Head-to-Head Comparison of Social Network Assessments in Stroke Survivors

Background and Purpose

Social networks influence human health and disease through direct biological and indirect psychosocial mechanisms. They have particular importance in neurologic disease because of support, information, and healthy behavior adoption that circulate in networks. Investigations into social networks as determinants of disease risk and health outcomes have historically relied on summary indices of social support, such as the Lubben Social Network Scale-Revised (LSNS-R) or the Stroke Social Network Scale (SSNS). We compared these 2 survey tools to personal network (PERSNET) mapping tool, a novel social network survey that facilitates detailed mapping of social network structure, extraction of quantitative network structural parameters, and characterization of the demographic and health parameters of each network member.

Methods

In a cohort of inpatient and outpatient stroke survivors, we administered LSNS-R, SSNS, and PERSNET in a randomized order to each patient. We used logistic regression to generate correlation matrices between LSNS-R scores, SSNS scores, and PERSNET's network structure (eg, size and density) and composition metrics (eg, percent kin in network). We also examined the relationship between LSNS-R-derived risk of social isolation with PERSNET-derived network size.

Results

We analyzed survey responses for 67 participants and found a significant correlation between LSNS-R, SSNS, and PERSNET-derived indices of network structure. We found no correlation between LSNS-R, SSNS, and PERSNET-derived metrics of network composition. Personal network mapping tool structural and compositional variables were also internally correlated. Social isolation defined by LSNS-R corresponded to a network size of <5.

Conclusions

Personal network mapping tool is a valid index of social network structure, with a significant correlation to validated indices of perceived social support. Personal network mapping tool also captures a novel range of health behavioral data that have not been well characterized by previous network surveys. Therefore, PERSNET offers a comprehensive social network assessment with visualization capabilities that quantifies the social environment in a valid and unique manner.

Blood CD9+ B cell, a biomarker of bronchiolitis obliterans syndrome after lung transplantation

Bronchiolitis obliterans syndrome is the main limitation for long-term survival after lung transplantation. Some specific B cell populations are associated with long-term graft acceptance. We aimed to monitor the B cell profile during early development of bronchiolitis obliterans syndrome after lung transplantation. The B cell longitudinal profile was analyzed in peripheral blood mononuclear cells from patients with bronchiolitis obliterans syndrome and patients who remained stable over 3 years of follow-up. CD24^hi CD38^hi transitional B cells were increased in stable patients only, and reached a peak 24 months after transplantation, whereas they remained unchanged in patients who developed a bronchiolitis obliterans syndrome. These CD24^hi CD38^hi transitional B cells specifically secrete IL-10 and express CD9. Thus, patients with a total CD9⁺ B cell frequency below 6.6% displayed significantly higher incidence of bronchiolitis obliterans syndrome (AUC = 0.836, PPV = 0.75, NPV = 1). These data are the first to associate IL-10-secreting CD24^hi CD38^hi transitional B cells expressing CD9 with better allograft outcome in lung transplant recipients. CD9-expressing B cells appear as a contributor to a favorable environment essential for the maintenance of long-term stable graft function and as a new predictive biomarker of bronchiolitis obliterans syndrome-free survival.

T-cell activation during exacerbations: a longitudinal study in refractory asthma

BACKGROUND

Asthma exacerbations represent the main source of costs and morbidity in asthma care, and drugs specifically designed to prevent exacerbations are needed. A prerequisite is to dispose of a precise knowledge of inflammatory events leading to exacerbations.

OBJECTIVE

To study T-cell activation during exacerbations from severe refractory asthmatics.

METHODS

Proportions of blood T-cell interleukin (IL)-13, interferon-gamma, IL-4, IL-5, IL-10 production and of CD4+CD25+(high)CD62L+CD45RO+ [T regulatory (Treg)] cells were determined by flow cytometry. Blood cytokine mRNA was studied by reverse transcription-polymerase chain reaction and the respective protein levels were determined by cytokine beads array. Depletion of Treg cells was performed to study their activation. T-cell cytokines were detected in parallel in induced sputum.

RESULTS

At baseline, T helper 2 (Th2) cells were increased in asthmatics, whereas T helper 1 (Th1) and Treg T cells were decreased. T helper 2 cells increased before exacerbations, followed by Th1 cells, in blood and induced sputum, albeit Treg cells decreased in parallel with IL-10-producing T cells. Concordant results were found at the mRNA level. The suppressive activity of Treg cells was impaired during exacerbations compared to baseline.

CONCLUSIONS

New insights are given into pathophysiology of asthma exacerbations: Although at baseline T-cell activation is Th2-biased, a mixed Th1/Th2 activation occurs during exacerbations. The Treg cell deficiency found at baseline in SRA increases during exacerbations.

Changes in endocannabinoid and palmitoylethanolamide levels in eye tissues of patients with diabetic retinopathy and age-related macular degeneration

Cannabinoid receptors and the endocannabinoids (anandamide (N-arachidonoylethanolamine--AEA) and 2-arachidonoylglycerol (2-AG)), as well as the AEA congener, palmitoylethanolamide (PEA), are involved in ocular physiology. We measured endocannabinoid and PEA levels by isotope-dilution liquid chromatography-mass spectrometric analysis in post-mortem eye tissues of patients with diabetic retinopathy (DR) or age-related macular degeneration (AMD). In eyes with DR, significantly enhanced levels of AEA were found in the retina ( approximately 1.8-fold), ciliary body ( approximately 1.5-fold) and, to a lesser extent, cornea ( approximately 1.3-fold). Surprisingly, 2-AG levels were significantly higher ( approximately 3-fold) only in the iris, whereas PEA levels only slightly increased ( approximately 1.3-fold) in the ciliary body. In eyes with AMD, significantly enhanced levels of AEA were found in the choroid ( approximately 1.3-fold), ciliary body ( approximately 1.4-fold) and cornea ( approximately 1.4-fold), whereas in the retina only a trend towards an increase ( approximately 1.5-fold) was observed. The tissue- and disease-selective nature of the changes observed suggests that the compounds analyzed here may play different roles in the control of eye function under different pathological conditions.

Diesel exhaust particles enhance T-cell activation in severe asthmatics

Prevalence of asthma is increasing in westernized countries. Epidemiological studies showed the impact of traffic pollution on the triggering of asthma symptoms and exacerbations, and this effect is mainly attributed to the polycyclic aromatic hydrocarbon core of diesel exhaust particles (DEP). However, although DEP induce IgE synthesis, little is known of their role on T-cell activation, the main cells orchestrating asthma inflammation. We assessed the effect of DEP on T-cell activation in severe uncontrolled asthmatics during (n = 13) and outside (n = 19) exacerbations. Results were compared with data obtained in healthy controls (n = 14). Peripheral blood mononuclear cells were cultured in the presence of low-dose DEP. T-cell activation markers, CD69 and CD25, interleukin-4 (IL-4) and interferon (IFN)-gamma production and T-cell proliferation were assessed by flow cytometry. DEP exposure increased the proportion of CD3+CD69+ T cells in all subjects. The proportion of CD25+ T cells increased under DEP stimulation in the exacerbation group only. IFN-gamma- and IL-4-producing T cells increased in both asthmatic groups, especially during exacerbations, but not in controls. This effect was more pronounced for IL-4. In response to DEP stimulation, T-cell proliferation increased in higher proportion in asthmatics compared with controls. These results show that DEP activate T cells in asthmatics only, with a higher effect during exacerbations. This is in keeping with epidemiological data which demonstrated that DEP trigger respiratory symptoms in asthmatics but not in controls. The higher effect of DEP in exacerbated asthmatics suggests that uncontrolled asthma is a risk factor for aggravation under exposure to traffic pollutants.

The process of transitioning to digital operations in a clinic setting

Transitioning to digital imaging operations in a department of radiology is often difficult for many radiologists, but it is a change that many have made effectively. Transitioning to digital operations in a clinic setting is even more difficult for the referring physician operating a business in the clinic. This paper will discuss our experience with transitioning several off site clinics to digital imaging operations. We will discuss the process followed to identify the physical equipment required to support clinic operations in a digital imaging environment, the process followed to help the physicians adjust their work patterns to allow them to practice in a digital imaging environment, and the benefits and pitfalls of implementing digital imaging in an off site clinic. Four off site clinic locations will be evaluated: 1. cancer clinic located immediately adjacent to the main hospital that relies heavily on CT and MRI images in their practice, 2. small clinic located about 60 miles from the main hospital that acquires xray images on site, 3. larger clinic located about 20 miles from the main hospital that acquires xray, MRI and CT images on site, 4. sports medicine clinic located about 2 miles from the main hospital that acquires xray images on site. Each of these clinics has a very different patient clientele and therefore operates differently in nearly all aspects of their daily operations. The physician's need for and use of film and digital images varies significantly between the sites and therefore each site has presented different challenges to our implementation process. As we explain the decisions that were made for each of these sites and reveal the methods that were used to help the physicians make the transition, the readers should be able to draw information that will be helpful to them as they make their own transition to a digital operation.

Application of the Unified Parkinson's Disease Rating Scale in progressive supranuclear palsy: factor analysis of the motor scale

An important criterion in scale validation is the demonstration of a stable factor structure. The Unified Parkinson's Disease Rating Scale (UPDRS) is widely used to assess Parkinson's disease (PD). The reliability and applicability of the motor subscale of the UPDRS (UPDRSm) when applied to patients diagnosed with progressive supranuclear palsy (PSP) is unknown. In a sample of 175 patients with PSP, factor analysis revealed five clinically distinct factors: two independent bradykinesia factors (axial/gait and extremities), one rigidity factor, and two independent tremor factors (rest and action). Two items (posture and rest head tremor) did not reach criteria for factor loadings. There was a high degree of internal consistency. These results suggest that UPDRSm is a reliable and applicable scale for assessing most aspects of PSP function as well as severity measures of five clinical disability domains.

[Modes of administration of inhaled corticosteroids in mild to moderate persistent asthma]

Inhaled corticosteroids are the treatment of choice for asthma. However, poor compliance by patients is one of the principal difficulties forced by clinicians. Thus, it seems important to propose the minimal daily number of doses. This study has compared the various modes of administration of inhaler corticosteroids and was carried out in patients with mild to moderate persistent asthma. Thus, comparing two to four doses per day shows an identical efficacy if the dose is less than 800 micrograms per day. At higher doses only two studies have been carried out and there are discordant results. The studies compare two doses versus one single dose per day and equally disagree with numerous works in favor of a single daily dose. In the single study carried out for at least twelve months the twice daily dose was the most effective. Thus it seems reasonable to suggest a single dose for mild persistent asthmatics. For moderate persistent asthmatics the choice between a single or twice daily dose would depend on the therapeutic compliance of the patient.

CBF, Myb, and Ets binding sites are important for activity of the core I element of the murine retrovirus SL3-3 in T lymphocytes

Transcriptional enhancers within the long terminal repeats of murine leukemia viruses are major determinants of the pathogenic properties of these viruses. Mutations were introduced into the adjacent binding sites for three transcription factors within the enhancer of the T-cell-lymphomagenic virus SL3-3. The sites that were tested were, in 5'-to-3' order, a binding site for core binding factor (CBF) called core II, a binding site for c-Myb, a site that binds members of the Ets family of factors, and a second CBF binding site called core I. Mutation of each site individually reduced transcriptional activity in T lymphocytes. However, mutation of the Myb and core I binding sites had larger effects than mutation of the Ets or core II site. The relative effects on transcription in T cells paralleled the effects of the same mutations on viral lymphomagenicity, consistent with the idea that the role of these sequences in viral lymphomagenicity is indeed to regulate transcription in T cells. Mutations were also introduced simultaneously into multiple sites in the SL3-3 enhancer. The inhibitory effects of these mutations indicated that the transcription factor in T cells that recognizes the core I element of SL3-3, presumably CBF, needed to synergize with one or more factors bound at the upstream sites to function. This was tested further by generating a multimer construct that contained five tandem core I elements linked to a basal long terminal repeat promoter. This construct was inactive in T cells. However, transcriptional activity was detected with a multimer construct in which the transcription factor binding sites upstream of the core were also present. These results are consistent with the hypothesis that CBF requires heterologous transcription factors bound at nearby sites to function in T cells.

Importance of a c-Myb binding site for lymphomagenesis by the retrovirus SL3-3

All murine leukemia viruses (MuLVs) and related type C retroviruses contain a highly conserved binding site for the Ets family of transcription factors within the enhancer sequences in the viral long terminal repeats (LTRs). The T-cell lymphomagenic MuLV SL3-3 (SL3-3) also contains a c-Myb binding site adjacent to the Ets site. The presence of this Myb site distinguishes SL3 from most other MuLVs. We tested the importance of these two sites for the lymphomagenicity of SL3-3. Mutation of the Ets site had little effect on viral pathogenicity, as it only slightly extended the latency period to disease onset. In contrast, mutation of the Myb site strongly inhibited pathogenicity, as only a minority of the inoculated mice developed tumors in the two mouse strains that were tested. All tumors that were induced by either mutant appeared to be lymphomas, and no evidence for reversion of either mutation was detected. The effects of the Ets and Myb site mutations on transcriptional activity of the SL3 LTR were tested by inserting the viral enhancer sequences into a plasmid containing the promoter region of the c-myc gene linked to a reporter gene. Mutation the Myb site almost eliminated enhancer activity in T lymphocytes, while mutation of the Ets site had smaller effects. Thus, the effects of the enhancer mutations on transcriptional activity in T cells paralleled their effects on viral lymphomagenicity. The absence of the c-Myb site in the LTR enhancer of the weakly lymphomagenic MuLV, Akv, likely contributes to the low pathogenicity of this virus relative to SL3-3. However, Moloney MuLV also lacks the Myb site in its LTR, although it induces T-cell lymphomas with a potency similar to that of SL3-3. Thus, it appears that SL3-3 and Moloney MuLV evolved genetic determinants of T-cell lymphomagenicity that are, at least in part, distinct.

Long-Term Results of Laparoscopic Burch

With recent advances in endoscopic surgery, suturing techniques, and balloon technology, laparoscopic Burch procedure with an extraperitoneal approach is a feasible alternative for the treatment of urinary stress incontinence (USI). Of 35 consecutive women (average age 47 yrs, average weight 193 lbs) undergoing laparoscopic Burch, 29 had genuine USI and 7 mixed incontinence with marked stress component. Average length of hospital stay was 2.4 days (range 1-10 days) and return to normal bladder function 5 days (range 2-8 days). The success rate, defined as dry at all times, was 90%, and 10% of women reported that they were much improved. Average follow-up was 20 months (range 4-38 mo). These results compare very favorably with findings published for conventional Burch.

Rapid three-dimensional display of the cerebral ventricles from noncontrast CT scans

Three-dimensional images of the cerebral ventricles may now be generated from routine serial axial or coronol noncontrast CT scans in 5-8 min and rotated in space interactively in 2-5-s to provide the physician with useful views of anatomic relationships difficult to depict in other ways.