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Objective: To identify biological and clinical predictors of acute kidney injury in subjects with acute lung injury.Design: Secondary data analysis from a multicenter, randomized clinical trial.Setting: Intensive care units in ten university medical centers.Patients: A total of 876 patients enrolled in the first National Heart, Lung, and Blood Institute Acute Respiratory Distress Syndrome Clinical Network trial.Interventions: Study subjects were randomized to receive a low tidal volume ventilation strategy and pharmacologic therapy with ketoconazole or lisofylline in a factorial design.Measurements and Main Results: We tested the association of baseline levels of interleukin-6, interleukin-8, interleukin-10, von Willebrand factor, tumor necrosis factor-[alpha], type I and II soluble tumor necrosis factor receptors (sTNFR-I and -II), protein C, plasminogen activator inhibitor-1 (PAI-1), surfactant protein-A, surfactant protein-D, and intracellular adhesion molecule-1 with subsequent acute kidney injury. Of 876 study participants who did not have end-stage renal disease, 209 (24%) developed acute kidney injury, defined as a rise in serum creatinine of >50% from baseline over the first four study days. The 180-day mortality rate for subjects with acute kidney injury was 58%, compared with 28% in those without acute kidney injury (p < .001). Interleukin-6, sTNFR-I, sTNFR-II, and PAI-1 levels were independently associated with acute kidney injury after adjustment for demographics, interventions, and severity of illness. A combination of clinical and biological predictors had the best area under the receiver operating characteristic curve, and the contribution of sTNFR-I and PAI-1 to this model was highly significant (p = .0003).Conclusions: Elevations in PAI-1, interleukin-6, and the sTNFRs in subjects with acute kidney injury suggest that disordered coagulation, inflammation, and neutrophil-endothelial interactions play important roles in the pathogenesis of acute kidney injury. The combination of these biological and clinical risk factors may have important and additive value in predictive models for acute kidney injury. [ABSTRACT FROM AUTHOR]

Background: Young men who have sex with men and transgender women (YMSM/TGW) have disproportionately high HIV incidence and lower preexposure prophylaxis (PrEP) adherence. Point-of-care (POC) urine tenofovir (TFV) rapid assay (UTRA) testing permits real-time monitoring for nonadherence within clinical settings. We performed UTRA testing among PrEP users to examine the relationship between low PrEP adherence and future PrEP discontinuation, and the accuracy of POC testing compared to gold-standard liquid chromatography tandem mass spectrometry (LC/MS/MS)., Methods: YMSM/TGW participants ( n  = 100) were recruited during a daily PrEP visit. Logistic regression models analyzed the relationship between the primary predictor of urine POC assay results (cutoff 1,500 ng/ml) and the primary outcome of PrEP discontinuation, defined as no PrEP follow-up or prescription within 120 days., Results: Overall, 19% of participants had low urine TFV and 21% discontinued PrEP, while 11% of participants self-reported low PrEP adherence (<4 pills per week), which was only 43% sensitive/84% specific in predicting low TFV levels and was not associated with PrEP discontinuation. Low urine TFV level predicted PrEP discontinuation [adjusted odds ratio (AOR) 6.1; 95% confidence interval (CI): 1.4-11; P  = 0.005] and was 71% sensitive/90% specific for discontinuation after 120 days. Compared to LC/MS/MS, UTRA testing had a 98% positive and 100% negative predictive value., Conclusions: In a sample of YMSM/TGW on daily PrEP, POC UTRA testing predicted PrEP discontinuation more accurately than self-reported adherence, with high predictive values compared to LC/MS/MS. UTRA testing may be a clinical tool for directing preventive interventions towards those likelier to discontinue PrEP despite ongoing HIV vulnerability., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Background: Limited data are available on the long-term clinical and immunologic consequences of SARS-CoV-2 infection in people with HIV (PWH)., Methods: We measured SARS-CoV-2-specific humoral and cellular responses in people with and without HIV recovering from COVID-19 ( n  = 39 and n  = 43, respectively) using binding antibody, surrogate virus neutralization, intracellular cytokine staining, and inflammatory marker assays. We identified individuals experiencing postacute sequelae of SARS-CoV-2 infection (PASC) and evaluated immunologic parameters. We used linear regression and generalized linear models to examine differences by HIV status in the magnitude of inflammatory and virus-specific antibody and T-cell responses, as well as differences in the prevalence of PASC., Results: Among PWH, we found broadly similar SARS-CoV-2-specific antibody and T-cell responses as compared with a well matched group of HIV-negative individuals. PWH had 70% lower relative levels of SARS-CoV-2-specific memory CD8 + T cells ( P  = 0.007) and 53% higher relative levels of PD-1+ SARS-CoV-2-specific CD4 + T cells ( P  = 0.007). Higher CD4 + /CD8 + ratio was associated with lower PD-1 expression on SARS-CoV-2-specific CD8 + T cells (0.34-fold effect, P  = 0.02). HIV status was strongly associated with PASC (odds ratio 4.01, P  = 0.008), and levels of certain inflammatory markers (IL-6, TNF-alpha, and IP-10) were associated with persistent symptoms., Conclusion: We identified potentially important differences in SARS-CoV-2-specific CD4 + and CD8 + T cells in PWH and HIV-negative participants that might have implications for long-term immunity conferred by natural infection. HIV status strongly predicted the presence of PASC. Larger and more detailed studies of PASC in PWH are urgently needed., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Objective: Having primary care delivered through a medical home is believed to improve mental health care delivery to children. Children with attention-deficit/hyperactivity disorder (ADHD) are commonly treated in pediatric practices, yet little is known about ADHD treatment patterns in medical homes. Our objective was to assess for treatment variation depending on parent-perceived medical home (PPMH) status. We hypothesized that having a PPMH would be associated with receiving ADHD treatments recommended by clinical guidelines., Methods: We used the 2016 National Survey of Children's Health-a nationally representative cross-sectional survey of children in the United States. Analyses included an unweighted sample of 4,252, representing 5.4 million children aged 3 to 17 years with parent-reported ADHD. Child characteristics were analyzed using descriptive statistics. Associations between ADHD treatment types and PPMH status were assessed using a multinomial logistic regression, adjusting for child characteristics., Results: Having a PPMH was associated with increased prevalence odds of children's receipt of medications alone for ADHD (vs no treatment). The prevalence odds of receiving behavioral treatment alone (vs medications alone) for ADHD decreased by 43% when children had a PPMH (95% confidence interval, 0.38-0.85, p = 0.01). PPMH status was not associated with a statistically significant difference in prevalence odds of receiving combination treatment (vs medications alone) for pediatric ADHD., Conclusion: Having a PPMH was associated with children's receipt of ADHD medications alone, but not behavioral treatments. Our findings suggest that medical homes may need further improvement to ensure that children with ADHD receive treatments as recommended by clinical guidelines., Competing Interests: Disclosure: The authors declare no conflict of interest., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

To assess SARS-CoV-2 outcomes, we matched a municipal COVID-19 registry and clinic rosters from a municipal primary care network containing a large HIV clinic and assessed clinical outcomes by HIV status. The risk of severe COVID-19 was higher among people with HIV (PWH, adjusted relative risk = 1.84, 95% confidence interval = 1.05-3.25), while SARS-CoV-2 incidence was lower despite higher testing rates. SARS-CoV-2 vaccination campaigns should prioritize PWH to prevent severe COVID-19 disease given potentially higher risk., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Coronavirus disease-2019 (COVID-19) threatens to further worsen HIV outcomes among people experiencing homelessness. We conducted an interrupted time-series analysis of care engagement and viral suppression among unhoused individuals in the 'POP-UP' low-barrier, high-intensity HIV primary care program during COVID-19. Among 85 patients, care engagement and viral suppression did not decrease in the 5 months following implementation of San Francisco's 'shelter-in-place' ordinance. Low-barrier, in-person HIV care for homeless individuals may be important for maintaining HIV outcomes during COVID-19., (Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.)

: The COVID-19 pandemic is expected to hinder US End the HIV Epidemic goals. We evaluated viral suppression and retention-in-care before and after telemedicine was instituted, in response to shelter-in-place mandates, in a large, urban HIV clinic. The odds of viral nonsuppression were 31% higher postshelter-in-place (95% confidence interval = 1.08-1.53) in spite of stable retention-in-care and visit volume, with disproportionate impact on homeless individuals. Measures to counteract the effect of COVID-19 on HIV outcomes are urgently needed.

Objective: To evaluate the effects of HIV preexposure prophylaxis (PrEP) with tenofovir disoproxial fumurate (TDF)/emtricitabine (FTC) on kidney function and kidney tubular health., Design: The Iniciativa Profilaxis Pre-Exposicion open-label extension (iPrEx-OLE) study enrolled former PrEP trial participants to receive open-label TDF/FTC. This study included 123 iPrEx-OLE participants who demonstrated PrEP adherence., Methods: We compared estimated glomerular filtration rate calculated using serum creatinine (eGFRcr), serum cystatin C (eGFRcys), and in combination (eGFRcr-cys), and a panel of 14 urine biomarkers reflecting kidney tubular health before and 6 months after PrEP initiation., Results: At baseline, mean eGFRcr, eGFRcys, and eGFRcr-cys were 108.3, 107.0, and 111.1 ml/min per 1.73 m, respectively. Six months after PrEP initiation, eGFRcr declined by -4% (95% CI: -5.7 to -2.4%), eGFRcys declined by -3.3% (95% CI: -8.3 to 1.9%), and eGFRcr-cys declined by -4.1% (95% CI: -7.5 to -0.7%). From the urine biomarker panel, α1-microglobulin and β2-microglobulin increased by 22.7% (95% CI: 11.8--34.7%) and 14.1% (95% CI: -6.1 to 38.6%), whereas chitinase-3-like 1 protein and monocyte chemoattractant protein-1 decreased by -37.7% (95% CI: -53.0 to -17.3%) and -15.6% (95% CI: -31.6 to 4.2%), respectively. Ten of the 14 urine biomarkers, including albumin, had estimated changes of less than 12% with wide confidence intervals., Conclusion: Six months of PrEP with TDF/FTC was associated with decreases in eGFRcr and eGFRcys. We also observed for the first time changes in flour of 14 urine biomarkers reflecting kidney tubular health. These findings demonstrate that PrEP has direct effects on eGFR and the proximal tubule.

Objective: HIV prevention and treatment studies demonstrate that pharmacologic adherence metrics are more accurate than self-report. Currently available metrics use liquid-chromatography/tandem-mass-spectrometry (LC-MS/MS), which is expensive and laboratory-based. We developed a specific and sensitive antibody against tenofovir, the backbone of treatment and prevention, but conversion to a lateral flow assay (LFA) - analogous to a urine pregnancy test - is required for point-of-care testing. We describe the development of the first LFA to measure antiretroviral adherence in real-time., Methods: Previous work in a directly observed therapy study of providing tenofovir disoproxil fumarate (TDF) to HIV-noninfected volunteers at various simulated adherence patterns defined the appropriate cut-off for the LFA (1500 ng tenofovir/ml urine). We developed the LFA using a sample pad for urine; a conjugate pad coated with TFV-specific antibodies conjugated to colloidal gold nanoparticles; a nitrocellulose membrane striped with tenofovir-antigen (test line) and a control line; with an absorbent pad to draw urine across the reaction membrane., Results: We tested 300 urine samples collected from the directly observed therapy study by this LFA and the gold-standard method of LC-MS/MS. The LFA demonstrated 97% specificity (95% CI 93-99%) and 99% sensitivity (94-100%) compared with LC-MS/MS. The LFA accurately classified 98% of patients who took a dose within 24 h as adherent., Conclusion: We describe the development and validation of the first point-of-care assay to measure short-term adherence to HIV prevention and treatment in routine settings. The assay is low-cost, easy-to-perform and measures the breakdown product (tenofovir) of both TDF and tenofovir alafenamide (TAF). This assay has the potential to improve HIV and PrEP outcomes worldwide by triggering differentiated service delivery with further study merited.

Purpose of Review: This review considers statistical issues in the design and analysis of the studies used to develop long-acting formulations of antiretrovirals for pre-exposure prophylaxis (PrEP)., Recent Finding: An abundant pipeline of products is maturing. Accelerating their evaluation as clinical products requires abandonment of noninferiority standards. Randomized trials should be based on the comparison of principled but innovative estimates of background HIV risk and enrich enrollment for those who do not desire current PrEP products. At every stage of testing, innovative analyses can be applied to help inform and accelerate later studies., Summary: The development of new long-acting PrEP regimens can be accelerated by innovations in design, ingenuity in synthesizing data sources, and application of causal inference methods.

Objective: We examined the relationship between urine tenofovir (TFV) levels measured with a novel immunoassay, which permits point-of-care testing, with HIV seroconversion and objective adherence metrics in a large preexposure prophylaxis (PrEP) demonstration project., Design: Secondary analysis of stored specimens from an open-label PrEP cohort study., Methods: We examined the association between undetectable urine TFV levels and HIV seroconversion in iPrEx open-label extension using generalized estimating equations. We examined rank correlations between levels of TFV and emtricitabine in urine, dried blood spots (DBS), and hair and determined the sensitivity and specificity of undetectable urine TFV for predicting dosing cut-offs in DBS., Results: The median urinary TFV level was 15 000 ng/ml in those who remained HIV-negative (n = 105; interquartile range: 1000-45 000); 5500 in those who eventually seroconverted (n = 11; interquartile range: 1000-12 500); and all were undetectable at seroconversion (n = 9; P < 0.001). Decreasing strata of urine TFV levels were associated with future HIV seroconversion (P = 0.03). An undetectable urine TFV was 100% sensitive and 81% specific when compared with an undetectable DBS TFV-diphosphate level and 69% sensitive, but 94% specific when compared with low adherence by DBS (<2 doses/week)., Conclusion: Urine TFV detection by a novel antibody-based assay was associated with protection from HIV acquisition among individuals on PrEP. Urine TFV levels were correlated with hair and DBS levels and undetectable urine TFV was 100% sensitive in detecting nonadherence. By implementing the immunoassay into a point-of-care strip test, PrEP nonadherence could be detected in real-time, allowing rapid intervention.

Existing HIV care cascade metrics fail to capture whether viremia is equally distributed in a population or concentrated within groups. We applied the Lorenz curve, which has been used to describe disparities in the distribution of income and other resources, to the distribution of viremia in a safety-net HIV clinic in 2012. Among 1855 established clinic patients, 1% of the population held 50% of the virus and 10% of the population held 94% of virus.

Objective: Engagement in care is key to successful HIV treatment in resource-limited settings; yet little is known about the magnitude and determinants of reengagement among patients out of care. We assessed patient-reported reasons for not returning to clinic, identified latent variables underlying these reasons, and examined their influence on subsequent care reengagement., Design: We used data from the East Africa International Epidemiologic Databases to Evaluate AIDS to identify a cohort of patients disengaged from care (>3 months late for last appointment, reporting no HIV care in preceding 3 months) (n = 430) who were interviewed about reasons why they stopped care. Among the 399 patients for whom follow-up data were available, 104 returned to clinic within a median observation time of 273 days (interquartile range: 165-325)., Methods: We conducted exploratory and confirmatory factor analyses (EFA, CFA) to identify latent variables underlying patient-reported reasons, then used these factors as predictors of time to clinic return in adjusted Cox regression models., Results: EFA and CFA findings suggested a six-factor structure that lent coherence to the range of barriers and motivations underlying care disengagement, including poverty, transport costs, and interference with work responsibilities; health system 'failures,' including poor treatment by providers; fearing disclosure of HIV status; feeling healthy; and treatment fatigue/seeking spiritual alternatives to medicine. Factors related to poverty and poor treatment predicted higher rate of return to clinic, whereas the treatment fatigue factor was suggestive of a reduced rate of return., Conclusion: Certain barriers to reengagement appear easier to overcome than factors such as treatment fatigue. Further research will be needed to identify the easiest, least expensive interventions to reengage patients lost to HIV care systems. Interpersonal interventions may continue to play an important role in addressing psychological barriers to retention.

Purpose of Review: We discuss selected statistical issues in the design and analysis of preexposure prophylaxis (PrEP) trials. The general principles may inform thinking for other interventions in HIV prevention., Recent Findings: To date, four different designs have been used to determine the effectiveness of PrEP: randomized, double-blind, placebo-controlled; randomized, open-label, immediate or delayed access; nonrandomized comparison of HIV incidence according to the level of drug detected; comparison of the observed HIV incidence to the expected rate using historical control data. Open-label trials of PrEP, which assess public health effectiveness, complement the placebo-controlled trials which established the biological efficacy of TDF/FTC. Future trials of PrEP will be highly challenging to design since a no PrEP group is difficult to justify and the natural control regimen, TDF/FTC, is highly efficacious., Summary: Standard statistical paradigms for noninferiority trials should be reconsidered for evaluating alternative PrEP regimens.

Background: Advanced age is the most important risk factor for atrial fibrillation (AF); however, the mechanism remains unknown. Telomeres, regions of DNA that shorten with cell division, are considered reliable markers of biological aging. We sought to examine the association between leukocyte telomere length (LTL) and incident AF in a large population-based cohort using direct LTL measurements and genetic data. To further explore our findings, we compared atrial cell telomere length and LTL in cardiac surgery patients., Methods and Results: Mean LTL and the TERT rs2736100 single nucleotide polymorphism were assessed as predictors of incident AF in the Cardiovascular Health Study (CHS). Among the surgical patients, within subject comparison of atrial cell telomere length versus LTL was assessed. Among 1639 CHS participants, we observed no relationship between mean LTL and incident AF before and after adjustment for potential confounders (adjusted hazard ratio, 1.09; 95% confidence interval: 0.92-1.29; P=0.299); chronologic age remained strongly associated with AF in the same model. No association was observed between the TERT rs2736100 single nucleotide polymorphism and incident AF (adjusted hazard ratio: 0.95; 95% confidence interval: 0.88-1.04; P=0.265). In 35 cardiac surgery patients (26 with AF), atrial cell telomere length was longer than LTL (1.19 ± 0.20 versus 1.02 ± 0.25 [T/S ratio], P<0.001), a finding that remained consistent within the AF subgroup., Conclusions: Our study revealed no evidence of an association between LTL and incident AF and no evidence of relative atrial cell telomere shortening in AF. Chronological aging independent of biological markers of aging is the primary risk factor for AF., (© 2014 American Heart Association, Inc.)

Background: There is intense interest in the role of programmed death 1 (PD-1) in causing persistent T-cell dysfunction in HIV infection. However, the impact of HIV infection and antiretroviral treatment (ART) on the expression of PD-1 on T cells is still poorly defined., Methods: PD-1 was measured longitudinally in a cohort of recently HIV-infected individuals (n = 121) who started ART early (<6 months after infection) vs. later (≥2 years after infection). PD-1 was also measured cross-sectionally in a diverse cohort of chronically HIV-infected adults (n = 206)., Results: PD-1 expression levels were high on CD8⁺ T cells during early HIV infection. PD-1 levels increased on both CD4⁺ and CD8⁺ T cells populations in those who delayed therapy (11 and 10%/year, respectively). PD-1 levels declined and were similar in those treated early vs. late after 1 year of ART. In both cohorts, PD-1 expression on CD4⁺ T cells was associated with CD4⁺ T-cell activation (CD38⁺HLA-DR⁺) and inversely with CD4⁺ cell count. In contrast, PD-1 expression on CD8⁺ T cells was most strongly associated with CD8⁺ T-cell activation and with plasma viral load in viremic individuals., Conclusion: Across two large cohorts of untreated and treated individuals, we found consistent associations between HIV RNA levels, CD8⁺ T-cell activation and PD-1 expression on CD8⁺ T cells. In contrast, CD4⁺ T-cell counts and CD4⁺ T-cell activation were more consistent correlates of PD-1 expression on CD4⁺ T cells. PD-1 expression appears to be driven by both direct antigen and homeostatic pathways.

Objective: Tenofovir disoproxil fumarate (TDF) pre-exposure prophylaxis decreases sexual acquisition of HIV infection. We sought to evaluate the renal safety of TDF in HIV-uninfected persons., Design and Methods: The Iniciativa Profilaxis Pre-Exposición (iPrEx) study randomly assigned 2499 HIV-seronegative men and transgender women who have sex with men (MSM) to receive oral daily TDF coformulated with emtricitabine (FTC/TDF) or placebo. Serum creatinine and phosphorus during randomized treatment and after discontinuation were measured, and creatinine clearance (CrCl) was estimated by the Cockcroft-Gault equation. Indicators of proximal renal tubulopathy (fractional excretion of phosphorus and uric acid, urine protein, and glucose) were measured in a substudy., Results: There was a small but statistically significant decrease in CrCl from baseline in the active arm, compared to placebo, which was first observed at week 4 (mean change: -2.4 vs. -1.1 ml/min; P=0.02), persisted through the last on-treatment visit (mean change: +0.3 vs. +1.8 ml/min; P=0.02), and resolved after stopping pre-exposure prophylaxis (mean change: -0.1 vs. 0.0 ml/min; P=0.83). The effect was confirmed when stratifying by drug detection. The effect of FTC/TDF on CrCl did not vary by race, age, or history of hypertension. There was no difference in serum phosphate trends between the treatment arms. In the substudy, two participants receiving placebo had indicators of tubulopathy., Conclusions: In HIV-seronegative MSM, randomization to FTC/TDF was associated with a very mild nonprogressive decrease in CrCl that was reversible and managed with routine serum creatinine monitoring.

Objective: Multiple single biomarkers have been associated with poor outcomes in acute lung injury; however, no single biomarker has sufficient discriminating power to clearly indicate prognosis. Using both derivation and replication cohorts, we tested novel risk reclassification methods to determine whether measurement of multiple plasma biomarkers at the time of acute lung injury diagnosis would improve mortality prediction in acute lung injury., Design: Analysis of plasma biomarker levels and prospectively collected clinical data from patients enrolled in two randomized controlled trials of ventilator therapy for acute lung injury., Setting: Intensive care units of university hospitals participating in the National Institutes of Health Acute Respiratory Distress Syndrome Network., Patients: Subjects enrolled in a trial of lower tidal volume ventilation (derivation cohort) and subjects enrolled in a trial of higher vs. lower positive end-expiratory pressure (replication cohort)., Interventions: None., Measurements and Main Results: The plasma biomarkers were intercellular adhesion molecule-1, von Willebrand factor, interleukin-8, soluble tumor necrosis factor receptor-1, and surfactant protein-D. In the derivation cohort (n = 547), adding data on these biomarkers to clinical predictors (Acute Physiology and Chronic Health Evaluation III score) at the time of study enrollment improved the accuracy of risk prediction, as reflected by a net reclassification improvement of 22% (95% confidence interval 13% to 32%; p < .001). In the replication cohort (n = 500), the net reclassification improvement was 17% (95% confidence interval 7% to 26%; p < .001). A reduced set of three biomarkers (interleukin-8, soluble tumor necrosis factor receptor-1, and surfactant protein-D) had nearly equivalent prognostic value in both cohorts., Conclusions: When combined with clinical data, plasma biomarkers measured at the onset of acute lung injury can improve the accuracy of risk prediction. Combining three or more biomarkers may be useful for selecting a high-risk acute lung injury population for enrollment in clinical trials of novel therapies.

Background: Previous reports showed that in California during the early 1990s, operative mortality rates for esophageal, pancreatic, and hepatic cancers were inversely related to hospital volume. It is unknown whether this information has affected referral patterns or operative mortality rates., Objectives: Data were analyzed for the 10 years that followed the period covered in the initial studies to determine if: (a) the operative mortality rates had decreased; and (b) a greater proportion of patients with esophageal, pancreatic, and hepatic cancers were treated at high-volume centers., Methods: Hospital discharge data were obtained for 8901 patients who had resections for cancer of the esophagus, 2404 patients; pancreas, 5294 patients; and liver, 1203 patients in California between 1995 and 2004. Logistic regression models were used to calculate adjusted mortality rates at high- and low-volume centers by year. The data were compared with the published results for California during the years 1990-1994., Results: Operative mortality rates decreased for esophageal, pancreatic, and hepatic resections during the more recent 10 years. Concomitantly, the proportion of patients treated at high-volume centers increased, as did the number of high-volume centers. There was a substantial increase in the proportion of esophagectomies performed in high-volume hospitals, while the overall number of esophagectomies dropped by 22%. For the other 2 operations, total volume and the volume in high-volume hospitals increased greatly, and the volume in low-volume hospitals was about the same during the 3 periods. The mortality rates decreased at all levels of the volume range. Finally, the performance from one period to the next in individual hospitals was mostly similar, but an occasional outlier was also noted., Conclusions: More resections for esophageal, pancreatic, and hepatic cancer were performed at high volume centers, but mortality rates decreased for all hospital categories. The data suggest that modern hospitals act as complex adaptive systems, whose outputs are determined from the interactions between internal agents and are resistant to analysis by isolating and studying the individual contributions. It is tempting to attribute the desirable changes in these data (eg, more operations being done in high volume centers and better mortality rates at all levels) as consequences of pressures over the past few decades on hospitals to assume greater responsibility for their quality of care and to become more integrated internally.Thus, many factors appear to influence the volume-outcome relationships, and the identity and individual contributions of these influences may be immune to reductionist analysis. There is substantial evidence that high volume should be part of high quality for these complex operations. Nevertheless, measuring outcomes directly, rather than concentrating on their correlates, may be a more reliable index of hospital performance.

Background and Purpose: Postsynaptic density (PSD)-93 and PSD-95 are the major membrane-associated guanylate kinases (MAGUKs) at excitatory synapses of the brain linking the N-methyl-d-aspartate receptor (NMDAR) with neuronal nitric oxide synthase (nNOS), which contributes to cell death after neonatal hypoxia-ischemia (HI). We investigated whether deletion of PSD-93 would dissociate the NMDAR from nNOS and be neuroprotective., Methods: Postnatal day 7 wild-type (+/+), heterozygous (+/-), and homozygous (-/-) PSD-93 knockout mice were subjected to HI by permanent ligation of the right carotid artery, followed by exposure to 8% O2/92% N2 for 1 hour. Brains were scored 5 days later for damage with cresyl violet and iron stains. Western blot and coimmunoprecipitation were used to determine the expression and association of the major PSD proteins., Results: There was no significant difference between PSD-93 (-/-) and (+/+) mice in mortality or degree of brain injury. In the absence of PSD-93, PSD-95 still interacted with NR2B and nNOS. Under physiological conditions, PSD-95, nNOS, NR2A, and NR2B were unaltered in the (-/-) pups. However, at 24 hours after HI, protein expression of PSD-95, nNOS, and NR2A but not NR2B was markedly higher in the (-/-) than in the (+/+) pups. In (+/+) pups, HI resulted in decreased expression of NR2A but not NR2B in cortex and decreased NR2A and NR2B expression in hippocampus, but this reduction was not observed in (-/-) pups., Conclusions: PSD-93 is not essential for baseline synaptic function but may participate in regulation of NMDAR-associated signaling pathways after HI injury. Deletion of PSD-93 alone does not provide neuroprotection after neonatal HI, possibly a result, in part, of upregulation of PSD-95. MAGUKs may substitute for one another, allowing normal NMDAR function in the postnatal period.

Background: There is controversy over whether seizures, the most common manifestation of neonatal brain injury, may themselves damage the developing brain., Objective: To determine if neonatal seizures are independently associated with brain injury in newborns with perinatal asphyxia., Methods: Ninety term neonates were studied with MRI and single-voxel (1)H-MRS on median day of life 6 (range 1 to 13 days). The severity of MR abnormality in the (1)H-MRS regions of interest was scored using a validated scale. Seizure severity was scored based on seizure frequency and duration, EEG findings, and anticonvulsant administration. Multivariable linear regression tested the independent association of seizure severity with impaired cerebral metabolism measured by lactate/choline and compromised neuronal integrity measured by N-acetylaspartate/choline in both regions., Results: Clinical seizures occurred in 33 of 90 infants (37%). Seizure severity was associated with increased lactate/choline in both the intervascular boundary zone (p < 0.001) and the basal nuclei (p = 0.011) when controlling for potential confounders of MRI abnormalities and amount of resuscitation at birth. Each increase in seizure score was independently associated with a 21% increase in lactate/choline in the intervascular boundary zone (95% CI, 5.1-38.2%) and a 15% increase in the basal nuclei (95% CI, 0.1-31.7%). Seizure severity was independently associated with diminished N-acetylaspartate/choline in the intervascular boundary zone (p = 0.034)., Conclusion: The severity of seizures in human newborns with perinatal asphyxia is independently associated with brain injury and is not limited to structural damage detectable by MRI.