Parvovirus B19 Infection in Children With Arterial Ischemic Stroke.

BACKGROUND AND PURPOSE: Case-control studies suggest that acute infection transiently increases the risk of childhood arterial ischemic stroke. We hypothesized that an unbiased pathogen discovery approach utilizing MassTag-polymerase chain reaction would identify pathogens in the blood of childhood arterial ischemic stroke cases. METHODS: The multicenter international VIPS study (Vascular Effects of Infection in Pediatric Stroke) enrolled arterial ischemic stroke cases, and stroke-free controls, aged 29 days through 18 years. Parental interview included questions on recent infections. In this pilot study, we used MassTag-polymerase chain reaction to test the plasma of the first 161 cases and 34 controls enrolled for a panel of 28 common bacterial and viral pathogens. RESULTS: Pathogen DNA was detected in no controls and 14 cases (8.7%): parvovirus B19 (n=10), herpesvirus 6 (n=2), adenovirus (n=1), and rhinovirus 6C (n=1). Parvovirus B19 infection was confirmed by serologies in all 10; infection was subclinical in 8. Four cases with parvovirus B19 had underlying congenital heart disease, whereas another 5 had a distinct arteriopathy involving a long-segment stenosis of the distal internal carotid and proximal middle cerebral arteries. CONCLUSIONS: Using MassTag-polymerase chain reaction, we detected parvovirus B19-a virus known to infect erythrocytes and endothelial cells-in some cases of childhood arterial ischemic stroke. This approach can generate new, testable hypotheses about childhood stroke pathogenesis.

Inflammatory Markers and Outcomes After Lacunar Stroke: Levels of Inflammatory Markers in Treatment of Stroke Study.

BACKGROUND AND PURPOSE: We hypothesized that concentrations of interleukin 6 (IL-6), serum amyloid A, tumor necrosis factor-α receptor 1, CD40 ligand, and monocyte chemoattractant protein 1 would predict recurrent ischemic stroke and major vascular events after recent lacunar stroke. METHODS: Levels of Inflammatory Markers in the Treatment of Stroke (LIMITS) was an international, multicenter, prospective ancillary biomarker study nested within the Secondary Prevention of Small Subcortical Strokes (SPS3) study, a Phase III trial in patients with recent lacunar stroke. Crude and Adjusted Cox proportional hazards models were used to calculate hazard ratios (HRs) and 95% confidence intervals (95% CI) for recurrence risks. RESULTS: Among 1244 patients with lacunar stroke (mean age, 63.3±10.8 years), there were 115 major vascular events (stroke, myocardial infarction, and vascular death). The risk of major vascular events increased with elevated concentrations of both tumor necrosis factor-α receptor 1 (adjusted HR per SD, 1.21; 95% CI, 1.05-1.41; P=0.01) and IL-6 (adjusted HR per SD, 1.10; 95% CI, 1.02-1.19; P=0.008). Compared with the bottom quartile (tumor necrosis factor-α receptor 1 <2.24 ng/L), those in the top quartile of tumor necrosis factor-α receptor 1 (>3.63 ng/L) were at twice the risk of major vascular events after adjusting for demographics (partially adjusted HR, 1.98; 95% CI, 1.11-3.52), though the effect attenuated after adjusting for other risk factors and statin use (adjusted HR, 1.68; 95% CI, 0.93-3.04). Serum amyloid A, CD40 ligand, and monocyte chemoattractant protein 1 were not associated with prognosis. CONCLUSIONS: Among recent lacunar stroke patients, IL-6 and TNF receptor concentrations predict risk of recurrent vascular events, and they are associated with the effect of antiplatelet therapies. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00059306.

Representativeness comparisons of nurse and computer charting of heart rate across nursing-intensity protocols.

Clinical teams in acute inpatient settings can greatly benefit from automated charting technologies that continuously monitor patient vital status. NewYork-Presbyterian has designed and developed a real-time patient monitoring system that integrates vital signs sensors, networking, and electronic health records, to allow for automatic charting of patient status. We evaluate the representativeness (a combination of agreement, safety and timing) of a core vital sign across nursing intensity care protocols for preliminary feasibility assessment. Our findings suggest an automated way of summarizing heart rate provides representation of true heart rate status and can facilitate alternatives approaches to burdensome manual nurse charting of physiological parameters.

High-sensitivity C-reactive protein and interleukin-6-dominant inflammation and ischemic stroke risk: the northern Manhattan study.

BACKGROUND AND PURPOSE: Interleukin-6 (IL-6) is a proinflammatory cytokine with known autoregulatory feedback mechanisms. We hypothesized that elevated high-sensitivity C-reactive protein (hsCRP) relative to IL-6 confers an increased risk of ischemic stroke (IS), and low hsCRP relative to IL-6 a decreased risk, for individuals in the prospective, multiethnic, population-based Northern Manhattan Study (NOMAS). METHODS: Serum hsCRP and IL-6 were measured in NOMAS participants at baseline. We created a trichotomized predictor based on the dominant biomarker in terms of quartiles: hsCRP-dominant, IL-6-dominant, and codominant groups. Cox proportional hazards models were used to calculate hazard ratios and 95% confidence intervals for the association between inflammatory biomarker group status and risk of incident IS. RESULTS: Of 3298 participants, both hsCRP and IL-6 were available in 1656 participants (mean follow-up, 7.8 years; 113 incident IS). The hsCRP-dominant group had increased risk of IS (adjusted hazard ratio, 2.62; 95% confidence interval, 1.56-4.41) and the IL-6-dominant group had decreased risk (adjusted hazard ratio, 0.38; 95% confidence interval, 0.18-0.82) when compared with the referent group, after adjusting for potential confounders. Model fit was improved using the inflammation-dominant construct, over either biomarker alone. CONCLUSIONS: In this multiethnic cohort, when hsCRP-quartile was higher than IL-6 quartile, IS risk was increased, and conversely when IL-6 quartiles were elevated relative to hsCRP, IS risk was decreased. Construct validity requires confirmation in other cohorts.

C-reactive protein as a prognostic marker after lacunar stroke: levels of inflammatory markers in the treatment of stroke study.

BACKGROUND AND PURPOSE: Inflammatory biomarkers predict incident and recurrent cardiac events, but their relationship to stroke prognosis is uncertain. We hypothesized that high-sensitivity C-reactive protein (hsCRP) predicts recurrent ischemic stroke after recent lacunar stroke. METHODS: Levels of Inflammatory Markers in the Treatment of Stroke (LIMITS) was an international, multicenter, prospective ancillary biomarker study nested within Secondary Prevention of Small Subcortical Strokes (SPS3), a phase III trial in patients with recent lacunar stroke. Patients were assigned in factorial design to aspirin versus aspirin plus clopidogrel, and higher versus lower blood pressure targets. Patients had blood samples collected at enrollment and hsCRP measured using nephelometry at a central laboratory. Cox proportional hazard models were used to calculate hazard ratios (HRs) and 95% confidence intervals (95% CIs) for recurrence risks before and after adjusting for demographics, comorbidities, and statin use. RESULTS: Among 1244 patients with lacunar stroke (mean age, 63.3±10.8 years), median hsCRP was 2.16 mg/L. There were 83 recurrent ischemic strokes (including 45 lacunes) and 115 major vascular events (stroke, myocardial infarction, and vascular death). Compared with the bottom quartile, those in the top quartile (hsCRP>4.86 mg/L) were at increased risk of recurrent ischemic stroke (unadjusted HR, 2.54; 95% CI, 1.30-4.96), even after adjusting for demographics and risk factors (adjusted HR, 2.32; 95% CI, 1.15-4.68). hsCRP predicted increased risk of major vascular events (top quartile adjusted HR, 2.04; 95% CI, 1.14-3.67). There was no interaction with randomized antiplatelet treatment. CONCLUSIONS: Among recent lacunar stroke patients, hsCRP levels predict the risk of recurrent strokes and other vascular events. hsCRP did not predict the response to dual antiplatelets. CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrials.gov. Unique identifier: NCT00059306.

Tumour necrosis factor receptor 1 and mortality in a multi-ethnic cohort: the Northern Manhattan Study.

OBJECTIVE: to study the association between soluble tumour necrosis factor receptor 1 (sTNFR1) levels and mortality in the population-based Northern Manhattan Study (NOMAS). METHODS: NOMAS is a multi-ethnic, community-based cohort study with mean 8.4 years of follow-up. sTNFR1 was measured using ELISA. Cox proportional hazards models were used to calculate hazard ratios and 95% confidence intervals (HR, 95% CI) for the association of sTNFR1 with risk of all-cause mortality after adjusting for relevant confounders. RESULTS: sTNFR1 measurements were available in 1,862 participants (mean age 69.2 ± 10.2 years) with 512 all-cause deaths. Median sTNFR1 was 2.28 ng/ml. Those with sTNFR1 levels in the highest quartile (Q4), compared with those with sTNFR1 in the lowest quartile (Q1), were at an increased risk of all-cause mortality (adjusted HR: 1.8, 95% CI: 1.4-2.4) and non-vascular mortality (adjusted HR: 2.5, 95% CI: 1.5-3.6), but not vascular mortality (adjusted HR: 1.3, 95% CI: 0.9-1.9). There were interactions between sTNFR1 quartiles and medical insurance-status [likelihood ratio test (LRT) with 3 degrees of freedom, Pinteraction = 0.02] and alcohol consumption (LRT with 3 degrees of freedom, Pinteraction < 0.01) for all-cause mortality. In participants with no insurance or Medicaid, those with sTNFR1 in the top quartile had nearly a threefold increased risk of total mortality than the lowest quartile (adjusted HR: 2.9, 95% CI: 1.9-4.4). CONCLUSION: in this multi-ethnic cohort, sTNFR1 was associated with all-cause and non-vascular mortality, particularly among those of a lower socioeconomic status.

Infectious burden and carotid plaque thickness: the northern Manhattan study.

BACKGROUND AND PURPOSE: The overall burden of prior infections may contribute to atherosclerosis and stroke risk. We hypothesized that serological evidence of common infections would be associated with carotid plaque thickness in a multiethnic cohort. METHODS: Antibody titers to 5 common infectious microorganisms (ie, Chlamydia pneumoniae, Helicobacter pylori, cytomegalovirus, and herpesvirus 1 and 2) were measured among stroke-free community participants and a weighted index of infectious burden was calculated based on Cox models previously derived for the association of each infection with stroke risk. High-resolution carotid duplex Doppler studies were used to assess maximum carotid plaque thickness. Weighted least squares regression was used to measure the association between infectious burden and maximum carotid plaque thickness after adjusting for other risk factors. RESULTS: Serological results for all 5 infectious organisms were available in 861 participants with maximum carotid plaque thickness measurements available (mean age, 67.2+/-9.6 years). Each individual infection was associated with stroke risk after adjusting for other risk factors. The infectious burden index (n=861) had a mean of 1.00+/-0.35 SD and a median of 1.08. Plaque was present in 52% of participants (mean, 0.90+/-1.04 mm). Infectious burden was associated with maximum carotid plaque thickness (adjusted increase in maximum carotid plaque thickness 0.09 mm; 95% CI, 0.03 to 0.15 mm per SD increase of infectious burden). CONCLUSIONS: A quantitative weighted index of infectious burden, derived from the magnitude of association of individual infections with stroke, was associated with carotid plaque thickness in this multiethnic cohort. These results lend support to the notion that past or chronic exposure to common infections, perhaps by exacerbating inflammation, contributes to atherosclerosis. Future studies are needed to confirm this hypothesis and to define optimal measures of infectious burden as a vascular risk factor.

Private Practice Administrative Costs Influenced by Insurance Payer Mix.

BACKGROUND: Increased staffing and oncology drug costs per physician, combined with decreased drug revenue, have made private hematology-oncology practices susceptible to increased financial risk. We hypothesized that practices with a higher combined commercial insurance (CCI) mix would experience greater inefficiencies in insurance billing (IB) processes and higher IB administrative costs. METHODS: A cross-sectional survey was administered to a national pool of private hematology-oncology practices. Practices were identified through the ASCO online registry. Participants self-reported insurance information. T and Wilcoxon rank sum tests were used to compare high (50% or more) Medicare payer mix groups and high (50% or more) CCI payer mix groups for practice operation indicators. These tests were also used to compare denial processing cost per Medicare patient and CCI patient. RESULTS: Among the 33 practices that responded to the survey, the mean total IB administrative cost for high Medicare payer mix groups was $191,646.25 (standard deviation [SD], $173,031.63), significantly lower (P = .0454) than the mean for high CCI groups at $476,280.00 (SD, $475,408.57). The mean annual cost per IB support staff member was significantly higher (P = .0453) in the high CCI group at $49,778.67 (SD = $14,896.32) compared with the mean cost in the high Medicare group, which was $39,413.08 (SD, $12,068.17). Medicare patient denial processing cost was significantly lower (P = .0237) than that for CCI patients. CONCLUSION: Practices with a high Medicare payer mix experience both lower mean cost per FTE IB support staff member and total overall IB administrative cost. Processing denials for reimbursement for Medicare patients requires fewer practice resources than does processing for CCI patients.

NCI designated cancer center funding not influenced by organizational structure.

BACKGROUND: National Cancer Institutes (NCI) designated cancer centers use one of three organizational structures. The hypothesis of this study is that there are differences in the amount of annual NCI funding per faculty member based on a cancer center's organizational structure. The study also considers the impact of secondary factors (i.e., the existence of a clinical program, the region and the size of the city in which the cancer center is located) on funding and the number of Howard Hughes Medical Institute (HHMI) investigators at each cancer center. RESULTS: Of the 63 cancer centers, 44 use a matrix structure, 16 have a freestanding structure, and three have a Department of Oncology structure. Kruskal-Wallis tests reveal no statistically significant differences in the amount of funding per faculty member or the number of HHMI investigators between centers with a matrix, freestanding or Department of Oncology structure. METHODS: Online research and telephone interviews with each cancer center were used to gather information, including: organizational structure, the presence of a clinical program, the number of faculty members, and the number of Howard Hughes Medical Institute investigators. Statistical tests were used to assess the impact which organizational structure has on the amount of funding per faculty member and number of HHMI investigators. CONCLUSION: While the results seem to suggest that the organizational structure of a given cancer center does not impact the amount of NCI funding or number of HHMI investigators which it attracts, the existence of this relationship is likely masked by the small sample size in this study. Further studies may be appropriate to examine the effect organizational structure has on other measurements which are relevant to cancer centers, such as quality and quantity of research produced.

Tumor vascular permeabilization by vascular-targeting photosensitization: effects, mechanism, and therapeutic implications.

PURPOSE: Loss of vascular barrier function has been observed shortly following vascular-targeting photodynamic therapy. However, the mechanism involved in this event is still not clear, and the therapeutic implications associated with this pathophysiologic change have not been fully explored. EXPERIMENTAL DESIGN: The effect of vascular-targeting photodynamic therapy on vascular barrier function was examined in both s.c. and orthotopic MatLyLu rat prostate tumor models and endothelial cells in vitro, using photosensitizer verteporfin. Vascular permeability to macromolecules (Evans blue-albumin and high molecular weight dextran) was assessed with dye extraction (ex vivo) and intravital microscopy (in vivo) methods. Intravital microscopy was also used to monitor tumor vascular functional changes after vascular-targeting photodynamic therapy. The effects of photosensitization on monolayer endothelial cell morphology and cytoskeleton structures were studied with immunofluorescence staining. RESULTS: Vascular-targeting photodynamic therapy induced vascular barrier dysfunction in the MatLyLu tumors. Thus, tumor uptake of macromolecules was significantly increased following photodynamic therapy treatments. In addition to vascular permeability increase, blood cell adherence to vessel wall was observed shortly after treatment, further suggesting the loss of endothelial integrity. Blood cell adhesion led to the formation of thrombi that can occlude blood vessels, causing vascular shutdown. However, viable tumor cells were often detected at tumor periphery after vascular-targeting photodynamic therapy. Endothelial cell barrier dysfunction following photodynamic therapy treatment was also observed in vitro by culturing monolayer endothelial cells on Transwell inserts. Immunofluorescence study revealed microtubule depolymerization shortly after photosensitization treatment and stress actin fiber formation thereafter. Consequently, endothelial cells were found to retract, and this endothelial morphologic change led to the formation of intercellular gaps. CONCLUSIONS: Vascular-targeting photodynamic therapy permeabilizes blood vessels through the formation of endothelial intercellular gaps, which are likely induced via endothelial cell microtubule depolymerization following vascular photosensitization. Loss of endothelial barrier function can ultimately lead to tumor vascular shutdown and has significant implications in drug transport and tumor cell metastasis.