Search

Abstract Background Public health nutrition recommendations and clinical dietary interventions emphasize eating healthy food at home, implicitly requiring household foodwork. Household foodwork is defined as the physical and mental tasks a household does for eating meals and snacks. Because no tools exist to measure it, how much time people spend doing household foodwork and the foodwork barriers they experience remain unknown. The objective of the present research was to develop the first stand-alone household foodwork assessment tool. Methods Through informal interviews with partners with lived experience, clinicians, and researchers, a literature review, a stakeholder meeting of advisors, and a two-round electronic Delphi process including face/content validation by expert panelists (n = 21), we developed the 10-question household foodwork interactional assessment questionnaire (FIA-Q10). An optional accompanying module was developed to collect self-identified demographic data to provide context for understanding how social-structural positionality factors may interact to influence foodwork. Results The FIA-Q10 assesses the domains of household composition, frequency of eating at home, special diets within a household, foodwork stress intensity, foodwork barriers, desired supports related to foodwork, and time use for foodwork. The FIA-Q10 measures time use for four subdomains of foodwork among individuals and their households: (1) planning, (2) getting, (3) preparing/cooking, and (4) cleaning up food. In the second Delphi round, the FIA-Q10 scored 95% for language appropriateness, 67% for visual appropriateness, 95% for relevance, 95% for representativeness, and 95% for distribution. Suggested improvements were implemented. All Delphi panelists (100%) reported they would consider using the FIA-Q10. Conclusions The FIA-Q10’s development is the first step towards a standardized assessment of foodwork, enabling examination of challenges in foodwork that may impact nutrition and nutrition equity. Future research will focus on FIA-Q10 validation in multiple populations.

Current diagnostic and therapeutic approaches for gliomas have limitations hindering survival outcomes. We propose spectroscopic magnetic resonance imaging as an adjunct to standard MRI to bridge these gaps. Spectroscopic MRI is a volumetric MRI technique capable of identifying tumor infiltration based on its elevated choline (Cho) and decreased N-acetylaspartate (NAA). We present the clinical translatability of spectroscopic imaging with a Cho/NAA ≥ 5x threshold for delineating a biopsy target in a patient diagnosed with non-enhancing glioma. Then, we describe the relationship between the undertreated tumor detected with metabolite imaging and overall survival (OS) from a pilot study of newly diagnosed GBM patients treated with belinostat and chemoradiation. Each cohort (control and belinostat) were split into subgroups using the median difference between pre-radiotherapy Cho/NAA ≥ 2x and the treated T1-weighted contrast-enhanced (T1w-CE) volume. We used the Kaplan–Meier estimator to calculate median OS for each subgroup. The median OS was 14.4 months when the difference between Cho/NAA ≥ 2x and T1w-CE volumes was higher than the median compared with 34.3 months when this difference was lower than the median. The T1w-CE volumes were similar in both subgroups. We find that patients who had lower volumes of undertreated tumors detected via spectroscopy had better survival outcomes.

This paper investigates the impact of homogeneous-heterogeneous chemical reactions on the flow between the coaxial cylinders with heat generation/absorption. From an engineering perspective, in energy absorber design for the shrinking and expanding of a circular metal tube in the production of extruding materials by stretching cylinders designing with great care is necessary to regulate skin friction and heat transfer rate. Studying processes in confined geometries enhances the basic knowledge of chemical kinetics and fluid dynamics. Researchers may increase the chemical processes efficiency/heat transfer activities by designing systems with an optimized flow and analysing the effects of reactions on flow. Both cost reductions and higher-quality products may result from this optimization. This research may yield insights with far-reaching implications across multiple disciplines. The modelled equations are transformed into ordinary differential equations by employing apt similarity transformations and obtained equations are solved using the collocation method with Probabilists’ Hermite polynomial. Graphs illustrating the variation of velocity, thermal, and concentration profiles have been plotted using the influence of various parameters. The increase in curvature parameter causes the velocity and thermal profile upsurge. The rise in heat source/sink parameter improves the heat transport. As the heterogeneous and homogeneous parameters upsurge, the concentration profile decreases.

The k shortest paths problem finds applications in multiple fields. Of particular interest in the transportation field is the variant of finding k simple shortest paths (KSSP), which has a higher complexity. This research presents a novel label-setting algorithm for the multi-destination KSSP problem in directed networks that obviates repeated applications of the algorithm to each destination (necessary in existing deviation-based algorithms), resulting in a significant computational speedup. It is shown that the proposed algorithm is exact and flexible enough to handle several variants of the problem by appropriately modifying the termination condition. Theoretically, it is also shown to be faster than state-of-the-art algorithms in sparse and dense networks whenever the number of labels created is sub-polynomial in network size. A heuristic method and optimized data structures are proposed to improve the algorithm’s scalability and worst-case performance. The computational results show that the proposed heuristic provides two to three orders of magnitude computational time speedups (29–1416 times across different networks) with negligible loss in solution quality (maximum average deviation of 0.167% from the optimal solution). Finally, a practical application of the proposed method is illustrated to determine the gravity of an edge (relative structural importance) in a network.

Introduction: Gentamicin (GEN) is a nephrotoxic aminoglycoside antibiotic, Hinokitiol, also known as (sng yóu chn) in traditional Chinese medicine (TCM), is a natural substance derived from the wood of certain coniferous trees, whereas hinokitiol (HE) has anti-inflammatory and antioxidant effects. This study aims to determine the protective role of HE in GEN-induced kidney injury. Methods: Adult male Wistar rats were separated into three groups: one treated with GEN, one treated with GEN plus pre-treated with HE, and one treated with vehicle. The levels of creatinine, urea, malondialdehyde (MDA), and superoxide dismutase (SOD) in the blood were measured. Histopathological alterations in renal tissues were evaluated, and inflammatory markers (TNF- α, NF-κB) were detected. Results: GEN-induced nephrotoxicity raised plasma creatinine, urea, and MDA levels while decreasing SOD levels. The combination of HE and GEN considerably reduced these effects. Renal tissues from GEN-treated rats showed lymphoid infiltration and tubular atrophy, whereas these were significantly decreased in the HE pre-treatment group. HE pre-treatment substantially reduced elevated TNF-α and NF-κB in GEN-administered animals. Conclusion: The study shows that HE protects against GEN-induced kidney damage, attributed to decreased oxidative stress and inflammatory pathways. These findings point to the possible therapeutic utility of HE in the treatment of GEN-related nephrotoxicity.

There is a critical need for an inactivation method that completely inactivates pathogens at the time of sample collection while maintaining the nucleic acid quality required for diagnostic PCR testing. This inactivation method is required to alleviate concerns about transmission potential, minimize shipping complications and cost, and enable testing in lower containment laboratories, thereby enhancing disease diagnostics through improved turn-around time. This study evaluated a panel of 10 surrogate viruses that represent highly pathogenic animal diseases. These results showed that a commercial PrimeStore® molecular transport media (PSMTM) completely inactivated all viruses tested by >99.99%, as determined by infectivity and serial passage assays. However, the detection of viral nucleic acid by qRT-PCR was comparable in PSMTM and control-treated conditions. These results were consistent when viruses were evaluated in the presence of biological material such as sera and cloacal swabs to mimic diagnostic sample conditions for non-avian and avian viruses, respectively. The results of this study may be utilized by diagnostic testing laboratories for highly pathogenic agents affecting animal and human populations. These results may be used to revise guidance for select agent diagnostic testing and the shipment of infectious substances.

Histone deacetylase inhibitors (HDACis) are drugs that target the epigenetic state of cells by modifying the compaction of chromatin through effects on histone acetylation. Gliomas often harbor a mutation of isocitrate dehydrogenase (IDH) 1 or 2 that leads to changes in their epigenetic state presenting a hypermethylator phenotype. We postulated that glioma cells with IDH mutation, due to the presence of epigenetic changes, will show increased sensitivity to HDACis. This hypothesis was tested by expressing mutant IDH1 with a point alteration—converting arginine 132 to histidine—within glioma cell lines that contain wild-type IDH1. Glioma cells engineered to express mutant IDH1 produced D-2-hydroxyglutarate as expected. When assessed for response to the pan-HDACi drug belinostat, mutant IDH1-expressing glioma cells were subjected to more potent inhibition of growth than the corresponding control cells. Increased sensitivity to belinostat correlated with the increased induction of apoptosis. Finally, a phase I trial assessing the addition of belinostat to standard-of-care therapy for newly diagnosed glioblastoma patients included one patient with a mutant IDH1 tumor. This mutant IDH1 tumor appeared to display greater sensitivity to the addition of belinostat than the other cases with wild-type IDH tumors based on both standard magnetic resonance imaging (MRI) and advanced spectroscopic MRI criteria. These data together suggest that IDH mutation status within gliomas may serve as a biomarker of response to HDACis.

Accurate radiation therapy (RT) targeting is crucial for glioblastoma treatment but may be challenging using clinical imaging alone due to the infiltrative nature of glioblastomas. Precise targeting by whole-brain spectroscopic MRI, which maps tumor metabolites including choline (Cho) and N-acetylaspartate (NAA), can quantify early treatment-induced molecular changes that other traditional modalities cannot measure. We developed a pipeline to determine how spectroscopic MRI changes during early RT are associated with patient outcomes to provide insight into the utility of adaptive RT planning. Data were obtained from a study (NCT03137888) where glioblastoma patients received high-dose RT guided by the pre-RT Cho/NAA twice normal (Cho/NAA ≥ 2x) volume, and received spectroscopic MRI scans pre- and mid-RT. Overlap statistics between pre- and mid-RT scans were used to quantify metabolic activity changes after two weeks of RT. Log-rank tests were used to quantify the relationship between imaging metrics and patient overall and progression-free survival (OS/PFS). Patients with lower Jaccard/Dice coefficients had longer PFS (p = 0.045 for both), and patients with lower Jaccard/Dice coefficients had higher OS trending towards significance (p = 0.060 for both). Cho/NAA ≥ 2x volumes changed significantly during early RT, putting healthy tissue at risk of irradiation, and warranting further study into using adaptive RT planning.

Introduction Reversible Cerebral Vasoconstriction Syndrome (RCVS) is a clinico‐radiographical syndrome characterized by severe thunderclap headache and reversible multifocal arterial vasoconstriction1. RCVS can be spontaneous or related to a trigger such as vasoactive medication/supplements. There is no previous data on the association of weight loss patch formulation in the genesis of unexplained RCVS. Methods A woman in her 40s presented with five days of recurrent acute onset severe right frontal headaches after starting Thrive weight loss patch supplementation. Head CT showed right frontal lobe hemorrhage with bilateral SAHs (Figure1). Brain MRI redemonstrated hemorrhages, numerous scattered foci of restricted diffusion, and a large area of restricted diffusion in the left insular cortex (Figure 2). Cerebral angiogram showed diffuse multifocal narrowing with a ‘beads‐on‐a‐string’ appearance of the cerebral vasculature and no aneurysms (Figure 3). Thrive patch contains undisclosed amounts of sympathomimetics and vasoactive compounds. Given the history, clinical symptoms of recurrent thunderclap headaches, and angiographic findings, the diagnosis of RCVS was made. Brain MRA 3 months after discharge showed no areas of cerebrovascular focal stenosis (Figure 4). At 4 month follow up, she reported 90% improvement of her symptoms. Results We report a temporal relationship between RCVS in a woman in her 40s and usage of a Thrive weight loss patch, which contains green tea extract, L‐arginine, 5‐hydroxytryptophan (5‐HTP), and Yerba Mate. We believe this report represents the first case of RCVS triggered by a weight loss patch. Multiple compounds within the Thrive patch have vasoactive properties that may contribute to RCVS genesis. Epigallocatechin (component of green tea extract) and 5‐HTP are metabolic compounds with potent vasoactive properties. They are components of weight loss and SSRI/SNRI medications respectively. Numerous studies have documented a temporal relationship between their use and subsequent development of RCVS2,3. Resolution of RCVS is reported after their discontinuation. Only one other case in our literature review investigated a patch modality in a temporal relationship with RCVS. It reported development and resolution of RCVS six days after nicotine patch use and discontinuation4. While Thrive patch does not contain nicotine, this case provides a further avenue for exploration as to whether pharmacokinetics of a patch modality influences a patient’s presentation with RCVS, as all prior reports document oral ingestion of substances. Conclusion Clinicians should be aware of the role of weight loss patches in RCVS, and their use should be assessed in large RCVS cohorts to clarify the association described in this report.

Radiation therapy (RT) is a critical part of definitive therapy for pediatric high-grade glioma (pHGG). RT is designed to treat residual tumor defined on conventional MRI (cMRI), though pHGG lesions may be ill-characterized on standard imaging. Spectroscopic MRI (sMRI) measures endogenous metabolite concentrations in the brain, and Choline (Cho)/N-acetylaspartate (NAA) ratio is a highly sensitive biomarker for metabolically active tumor. We provide a preliminary report of our study introducing a novel treatment approach of whole brain sMRI-guided proton therapy for pHGG. An observational cohort (c1 = 10 patients) receives standard of care RT; a therapeutic cohort (c2 = 15 patients) receives sMRI-guided proton RT. All patients undergo cMRI and sMRI, a high-resolution 3D whole-brain echo-planar spectroscopic imaging (EPSI) sequence (interpolated resolution of 12 µL) prior to RT and at several follow-up timepoints integrated into diagnostic scans. Treatment volumes are defined by cMRI for c1 and by cMRI and Cho/NAA ≥ 2x for c2. A longitudinal imaging database is used to quantify changes in lesion and metabolite volumes. Four subjects have been enrolled (c1 = 1/c2 = 3) with sMRI imaging follow-up of 4–18 months. Preliminary data suggest sMRI improves identification of pHGG infiltration based on abnormal metabolic activity, and using proton therapy to target sMRI-defined high-risk regions is safe and feasible.

Glioblastoma (GBM) is a fatal disease, with poor prognosis exacerbated by difficulty in assessing tumor extent with imaging. Spectroscopic MRI (sMRI) is a non-contrast imaging technique measuring endogenous metabolite levels of the brain that can serve as biomarkers for tumor extension. We completed a three-site study to assess survival benefits of GBM patients when treated with escalated radiation dose guided by metabolic abnormalities in sMRI. Escalated radiation led to complex post-treatment imaging, requiring unique approaches to discern tumor progression from radiation-related treatment effect through our quantitative imaging platform. The purpose of this study is to determine true tumor recurrence timepoints for patients in our dose-escalation multisite study using novel methodology and to report on median progression-free survival (PFS). Follow-up imaging for all 30 trial patients were collected, lesion volumes segmented and graphed, and imaging uploaded to our platform for visual interpretation. Eighteen months post-enrollment, the median PFS was 16.6 months with a median time to follow-up of 20.3 months. With this new treatment paradigm, incidence rate of tumor recurrence one year from treatment is 30% compared to 60–70% failure under standard care. Based on the delayed tumor progression and improved survival, a randomized phase II trial is under development (EAF211).

Abstract It is well established that an elevated potassium level (hyperkalemia) is associated with a risk of adverse events including morbidity, mortality and healthcare system cost. Hyperkalemia is commonly encountered in many chronic conditions including kidney disease, diabetes and heart failure. Furthermore, hyperkalemia may result from the use of renin-angiotensin-aldosterone system inhibitors (RAASi), which are disease-modifying treatments for these conditions. Therefore, balancing the benefits of optimizing treatment with RAASi while mitigating hyperkalemia is crucial to ensure patients are optimally treated. In this review, we will briefly discuss the definition, causes, epidemiology and consequences of hyperkalemia. The majority of the review will be focused on management of hyperkalemia in the acute and chronic setting, emphasizing contemporary approaches and evolving data on the relevance of dietary restriction and the use of novel potassium binders.

Background: Individuals with chronic kidney disease (CKD) can develop metabolic acidosis which, in turn, is associated with faster progression of CKD and an increased need for dialysis. Oral sodium bicarbonate (the current standard of care therapy for metabolic acidosis) is poorly tolerated leading to low adherence. Base-producing or alkalizing Fruit and vegetables have potential as an alternative treatment for metabolic acidosis as they have been shown to reduce acid load arising from the diet. Objective: This trial will evaluate the feasibility of providing base-producing fruit and vegetables as a dietary treatment for metabolic acidosis, compared with oral sodium bicarbonate. Design: A 2-arm, open-label, dual-center, randomized controlled feasibility trial. Setting: Two Canadian sites: a nephrology clinic in Winnipeg, Manitoba, and a nephrology clinic in Halifax, Nova Scotia. Participants: Adult participants with G3-G5 CKD and metabolic acidosis. Measurements: Participants will undergo baseline measurements and attend 5 study visits over 12 months at which they will have a measurement of feasibility criteria as well as blood pressure, blood and urine biochemistry, 5-repetition chair stand test (STS5), and questionnaires to assess quality of life and symptoms. Furthermore, participants fill out Automated Self-Administered 24-hour recalls (ASA-24) in the beginning, middle, and end of trial. Methods: A total of 40 eligible participants will be randomized 1:1 to either base-producing fruit and vegetables (experimental) group or sodium bicarbonate (control) group, beginning from a daily dose of 1500 mg. Limitations: Using self-administered dietary assessments, lack of supervision over the consumption of study treatments and the possible disappointment of the control group for not receiving fruit and vegetables would be considered as limitations for this study. However, we are planning to undertake proper practices to overcome the possible limitations. These practices are discussed throughout the article in detail. Conclusions: This study will generate data on base-producing fruit and vegetables consumption as a dietary treatment for metabolic acidosis in CKD. The data will be used to design a future multi-center trial looking at slowing CKD progression in people with metabolic acidosis. Trial Registration: This study is registered on clinicaltrials.gov with the identifier NCT05113641.

Background: Prolonged warm ischemia time (WIT) and cold ischemia time (CIT) are independently associated with post-transplant graft failure; their combined impact has not been previously studied. We explored the effect of combined WIT/CIT on all-cause graft failure following kidney transplantation. Methods: The Scientific Registry of Transplant Recipients was used to identify kidney transplant recipients from January 2000 to March 2015 (after which WIT was no longer separately reported), and patients were followed until September 2017. A combined WIT/CIT variable (excluding extreme values) was separately derived for live and deceased donor recipients using cubic splines; for live donor recipients, the reference group was WIT 10 to 0 to

Background: Patients receiving maintenance hemodialysis frequently require ambulance transport to the emergency department (ambulance-ED transport). Identifying predictors of outcomes after ambulance-ED transport, especially the need for timely dialysis, is important to health care providers. Objective: The purpose of this study was to derive a risk-prediction model for urgent dialysis after ambulance-ED transport. Design: Observational cohort study Setting and Patients: All ambulance-ED transports among incident and prevalent patients receiving maintenance hemodialysis affiliated with a regional dialysis program (catchment area of approximately 750 000 individuals) from 2014 to 2018. Measurements: Patients’ vital signs (systolic blood pressure, oxygen saturation, respiratory rate, and heart rate) at the time of paramedic transport and time since last dialysis were utilized as predictors for the outcome of interest. The primary outcome was urgent dialysis (defined as dialysis in a monitored setting within 24 hours of ED arrival or dialysis within 24 hours with the first ED patient blood potassium level >6.5 mmol/L) for an unscheduled indication. Secondary outcomes included, hospitalization, hospital length of stay, and in-hospital mortality. Methods: A logistic regression model to predict outcomes of urgent dialysis. Discrimination and calibration were assessed using the C-statistic and Hosmer-Lemeshow test. Results: Among 878 ED visits, 63 (7.2%) required urgent dialysis. Hypoxemia (odds ratio [OR]: 4.04, 95% confidence interval [CI]: 1.75-9.33) and time from last dialysis of 24 to 48 hours (OR: 3.43, 95% CI: 1.05-11.9) and >48 hours (OR: 9.22, 95% CI: 3.37-25.23) were strongly associated with urgent dialysis. A risk-prediction model incorporating patients’ vital signs and time from last dialysis had good discrimination (C-statistic 0.8217) and calibration (Hosmer-Lemeshow goodness of fit P value .8899). Urgent dialysis patients were more likely to be hospitalized (63% vs 34%), but there were no differences in inpatient mortality or length of stay. Limitations: Missing data, requires external validation. Conclusion: We derived a risk-prediction model for urgent dialysis that may better guide appropriate transport and care for patients requiring ambulance-ED transport.

Background: There is little data modeling the impact of deemed consent legislation (eligible individuals who do not register their decision to decline to be a donor are presumed to consent after death) on outcomes for individuals with kidney failure. Objective: To estimate the change in life-years (LYs) and quality-adjusted life-years (QALYs) resulting from different changes in the rate of deceased donor kidney transplantation associated with deemed consent legislation and health system transformation. Design: Dynamic Decision Analytic Model. Setting: This modeling study included kidney failure patients in Atlantic Canada (all of whom receive their kidney transplants in Halifax, Nova Scotia). The adoption of deemed consent legislation was the intervention, and opt-in (the status quo) was the reference comparator. Patients: Prevalent kidney failure patients at the end of 2019 in all of Atlantic Canada (N = 3615) served as the starting population. Methods: We compared expected outcomes between the intervention and comparator. Changes in QALYs and total LYs were modeled under different changes to the proportion of patients receiving a deceased donor kidney transplant (from –10% to 20%) resulting from deemed consent relative to the status quo. Changes in QALYs and LYs were reported for 3 different time horizons (5, 10, and 30 years). Uncertainty around QALYs and total LYs was reported using 95% confidence intervals (CIs) constructed from a probabilistic sensitivity analysis using 1000 Monte Carlo Simulations. Results: The increase in QALYs ranged from 7 QALYs (95% CI: 5-10) with a 5% increase using a 5-year time frame to 882 QALYs (95% CI: 619-1144) with a 20% increase over a 30-year time frame. Parallel changes in total LYs were also observed. In contrast, decreases in deceased donor kidney transplantation resulted in a loss of QALYs (for example, –463 QALYs; 95% CI: –633 to –306 for a 10% decrease over a 30-year time frame). Using the most optimistic scenario (a 20% increase), there was an 18% increase in the cumulative number of deceased donor kidney transplant recipients over a 30-year observation period. Limitations: The results are subject to uncertainty depending on changes to the dialysis or transplant population that were not modeled and that may not be fully captured with probabilistic sensitivity analysis. Conclusions: Deemed consent legislation will lead to variable changes in QALYs and total LYs for the kidney failure population, depending on the degree to which deceased donor transplantation rates change and the time horizon of observation. This modeling study may serve as a baseline to monitor the future impact of deemed consent legislation.

Rajagopalan Venkatraman, Kandhan Karthik, Cherian Belinda, Ramamurthy Balaji Department of Anaesthesia, SRM Medical College Hospital and Research Centre, Potheri, Tamilnadu, 603203, IndiaCorrespondence: Rajagopalan VenkatramanDepartment of Anaesthesia, SRM Medical College Hospital and Research Centre, Potheri, 603203, Tamilnadu, IndiaTel +91 9894581455Email drvenkat94@gmail.comBackground and Aims: Ultrasound-guided (UG) mandibular nerve block is effective for providing postoperative analgesia in mandibular fracture surgeries. The pre-emptive nerve blockade prolongs the duration of postoperative analgesia and reduces the consumption of intraoperative opioids. The aim of this prospective, randomized, single-blinded study was to compare the efficacy of pre-emptive and postoperative UG mandibular nerve block for postoperative analgesia in mandibular fracture surgeries.Methods: Sixty patients scheduled for unilateral mandibular fracture surgeries were randomly divided into two groups by computer-generated random numbers and sealed envelope method: Group A received UG mandibular nerve block before surgical incision and group B received after surgery with ropivacaine 0.5% 10mL. The second anesthesiologist, who was blinded to the group involved, monitored the patient. The patients as well as the statistician were also blinded. The patients were started on patient-controlled analgesia (PCA) morphine with bolus 1mg and a lockout interval of 10min. The morphine consumption for 24h was recorded. The pain was assessed by the VAS score. The additional intraoperative fentanyl consumption and time for a request for rescue analgesic were recorded.Results: The total morphine consumption was reduced in group A (4.566± 0.717mg) than group B (5.93± 0.876mg) with a p-value of < 0.0001. The time for a request for rescue analgesic was also prolonged in group A (794.08± 89.561min) than group B (505.333± 3.159min). In group A, only four patients required an additional dose of fentanyl as against 11 patients in group B. The heart rate was also lower in group A 30min after the administration of the block and persisted for two hours intraoperatively.Conclusion: Pre-emptive ultrasound-guided mandibular nerve block reduces morphine consumption, prolongs the time for a request for rescue analgesic, reduces intraoperative fentanyl consumption, provides better control of intraoperative heart rate, and better pain scores postoperatively when compared to the postoperative mandibular nerve block.Keywords: mandibular fracture, mandibular nerve, postoperative pain, ultrasound-guided, visual analog scale

Extreme heat puts tremendous stress on human health and limits people’s ability to work, travel, and socialize outdoors. To mitigate heat in public spaces, thermal conditions must be assessed in the context of human exposure and space use. Mean Radiant Temperature (MRT) is an integrated radiation metric that quantifies the total heat load on the human body and is a driving parameter in many thermal comfort indices. Current sensor systems to measure MRT are expensive and bulky (6-directional setup) or slow and inaccurate (globe thermometers) and do not sense space use. This engineering systems paper introduces the hardware and software setup of a novel, low-cost thermal and visual sensing device (MaRTiny). The system collects meteorological data, concurrently counts the number of people in the shade and sun, and streams the results to an Amazon Web Services (AWS) server. MaRTiny integrates various micro-controllers to collect weather data relevant to human thermal exposure: air temperature, humidity, wind speed, globe temperature, and UV radiation. To detect people in the shade and Sun, we implemented state of the art object detection and shade detection models on an NVIDIA Jetson Nano. The system was tested in the field, showing that meteorological observations compared reasonably well to MaRTy observations (high-end human-biometeorological station) when both sensor systems were fully sun-exposed. To overcome potential sensing errors due to different exposure levels, we estimated MRT from MaRTiny weather observations using machine learning (SVM), which improved RMSE. This paper focuses on the development of the MaRTiny system and lays the foundation for fundamental research in urban climate science to investigate how people use public spaces under extreme heat to inform active shade management and urban design in cities.

Peer review aims to select articles for publication and to improve articles before publication. We believe that this process can be infused by kindness without losing rigor. In 2014, the founding editorial team of the Canadian Journal of Kidney Health and Disease (CJKHD) made an explicit commitment to treat authors as we would wish to be treated ourselves. This broader group of authors reaffirms this principle, for which we suggest the terminology “supportive review.”

Background: Glomerulonephritis (GN) is a leading cause of kidney failure and accounts for 20% of incident cases of end-stage kidney disease (ESKD) in Canada annually. Reversal of kidney injury and prevention of progression to kidney failure is possible; however, limited knowledge of underlying disease mechanisms and lack of noninvasive biomarkers and therapeutic targets are major barriers to successful therapeutic intervention. Multicenter approaches that link longitudinal clinical and outcomes data with serial biologic specimen collection would help bridge this gap. Objective: To establish a national, patient-centered, multidimensional web-based clinical database and federated virtual biobank to conduct human-based molecular and clinical research in GN in Canada. Design: Multicenter, prospective observational registry, starting in 2019. Setting: Nine participating Canadian tertiary care centers. Patients: Adult patients with a histopathologic pattern of injury consistent with IgA nephropathy, focal and segmental glomerulosclerosis, minimal change disease, membranous nephropathy, C3 glomerulopathy, and membranoproliferative GN recruited within 24 months of biopsy. Measurements: Initial visits include detailed clinical, histopathological, and laboratory data collection, blood, urine, and tonsil swab biospecimen collection, and a self-administered quality of life questionnaire. Follow-up clinical and laboratory data collection, biospecimen collection, and questionnaires are obtained every 6 months thereafter. Methods: Patients receive care as defined by their physician, with study visits scheduled every 6 months. Patients are followed until death, dialysis, transplantation, or withdrawal from the study. Key outcomes include a composite of ESKD or a 40% decline in estimated glomerular filtration rate (eGFR) at 2 years, rate of kidney function decline, and remission of proteinuria. Clinical and molecular phenotypical data will be analyzed by GN subtype to identify disease predictors and discover therapeutic targets. Limitations: Given the relative rarity of individual glomerular diseases, one of the major challenges is patient recruitment. Initial registry studies may be underpowered to detect small differences in clinically meaningful outcomes such as ESKD or death due to small sample sizes and short duration of follow-up in the initial 2-year phase of the study. Conclusions: The Canadian Glomerulonephritis Registry (CGNR) supports national collaborative efforts to study glomerular disease patients and their outcomes. Trial registration: NCT03460054.

Purpose of the program: This article provides guidance on optimizing the management of pediatric patients with end-stage kidney disease (ESKD) who will be or are being treated with any form of home or in-center dialysis during the COVID-19 pandemic. The goals are to provide the best possible care for pediatric patients with ESKD during the pandemic and ensure the health care team’s safety. Sources of information: The core of these rapid guidelines is derived from the Canadian Society of Nephrology (CSN) consensus recommendations for adult patients recently published in the Canadian Journal of Kidney Health and Disease ( CJKHD ). We also consulted specific documents from other national and international agencies focused on pediatric kidney health. Additional information was obtained by formal review of the published academic literature relevant to pediatric home or in-center hemodialysis. Methods: The Leadership of the Canadian Association of Paediatric Nephrologists (CAPN), which is affiliated with the CSN, solicited a team of clinicians and researchers with expertise in pediatric home and in-center dialysis. The goal was to adapt the guidelines recently adopted for Canadian adult dialysis patients for pediatric-specific settings. These included specific COVID-19-related themes that apply to dialysis in a Canadian environment, as determined by a group of senior renal leaders. Expert clinicians and nurses with deep expertise in pediatric home and in-center dialysis reviewed the revised pediatric guidelines. Key findings: We identified 7 broad areas of home dialysis practice management that may be affected by the COVID-19 pandemic: (1) peritoneal dialysis catheter placement, (2) home dialysis training, (3) home dialysis management, (4) personal protective equipment, (5) product delivery, (6) minimizing direct health care providers and patient contact, and (7) caregivers support in the community. In addition, we identified 8 broad areas of in-center dialysis practice management that may be affected by the COVID-19 pandemic: (1) identification of patients with COVID-19, (2) hemodialysis of patients with confirmed COVID-19, (3) hemodialysis of patients not yet known to have COVID-19, (4) management of visitors to the dialysis unit, (5) handling COVID-19 testing of patients and staff, (6) safe practices during resuscitation procedures in a pandemic, (7) routine hemodialysis care, and (8) hemodialysis care under fixed dialysis resources. We make specific suggestions and recommendations for each of these areas. Limitations: At the time when we started this work, we knew that evidence on the topic of pediatric dialysis and COVID-19 would be severely limited, and our resources were also limited. We did not, therefore, do formal systematic review or meta-analysis. We did not evaluate our specific suggestions in the clinical environment. Thus, this article’s advice and recommendations are primarily expert opinions and subject to the biases associated with this level of evidence. To expedite the publication of this work, we created a parallel review process that may not be as robust as standard arms’ length peer-review processes. Implications: We intend these recommendations to help provide the best care possible for pediatric patients prescribed in-center or home dialysis during the COVID-19 pandemic, a time of altered priorities and reduced resources.

Purpose: The Canadian Nephrology Trials Network (CNTN) was formed in 2014 to support Canadian researchers in developing, designing, and conducting prospective studies in nephrology. In response to the changing landscape and needs within the Canadian nephrology research community, an interest in further growth and development of the network was identified. In the following report, we describe the process undertaken to re-envision the network through the creation of 3 new committees and how the committees are facilitating change and growth within the CNTN for future sustainability. Sources of information: To understand areas for improvement and capacity building, the organization charged with overseeing the CNTN, Canadians Seeking Solutions and Innovations to Overcome Chronic Kidney Disease (Can-SOLVE CKD), began by conducting an environmental scan. As well, 2 informal surveys were sent to nephrology professionals (who were members of the CNTN and the Canadian Society of Nephrology) and patient partners (from Can-SOLVE CKD). Methods: In September 2018, 44 CNTN members and other stakeholders from across Canada (including patient partners and representatives from research funding agencies) convened for a 2-day visioning workshop in Mississauga, Ontario. The agenda for this workshop was largely based on the results from the informal surveys. CNTN leadership participated and chose other workshop participants through informal stakeholder mapping and purposeful recruitment. Patient partners were recruited to participate in the workshop through advertisement within the Can-SOLVE-CKD patient council. The survey results and discussion questions were presented to participants at the workshop who, in turn, discussed in large- and small-group session ways in which the CNTN might be expanded. Results: Surveys of patient partners indicated that they would like to see greater involvement of patients in the research process. Surveys of researchers indicated that they wanted more support and resources for coordinating prospective trials. The themes which emerged from the workshop discussions were peer review, engagement, and training. These themes were broadened and formally re-named to Scientific Operations, Communications and Engagement, and Capacity Building. A working committee, each co-led by a nephrologist with research experience and a patient partner, was created to advance each of these identified themes. An executive committee was created to provide overall strategic leadership and governance to the network. The Scientific Operations Committee conducts peer reviews; provides letters of endorsement after peer review; and holds semi-annual in-person meetings where researchers can present their proposals and obtain feedback from multiple stakeholders, including patients. The Communications and Engagement Committee publishes a quarterly newsletter, engages the community on Twitter, and reaches out to community sites and new nephrologists to engage them in research. The Capacity Building Committee conducts webinars to encourage patient partners to develop their own research questions and is developing a hub-and-spoke model to improve research collaboration. Limitations: We did not conduct formal stakeholder mapping. Only attendees of the visioning workshop provided input, and not everyone’s comment or opinion was included in the workshop report. Perspectives were limited to the sample of people who attended the workshop or were surveyed and may not reflect perspectives of all stakeholders in nephrology research in Canada. We did not use formal qualitative methodology to summarize the workshops. Implications: Renewed areas of focus and related committees within the CNTN could lead to an increased capacity for nephrology research, increased engagement and collaboration with researchers, a higher likelihood of funding with rigorous peer review, and more clinical trials and multicenter collaborative prospective research being conducted in Canada.

Background: Live donor (LD) kidney transplantation is the best option for patients with end-stage kidney disease (ESKD). However, this may not be the best option if a patient’s donor is older and considerably smaller in weight. Patient (A) with a less than ideal donor (Donor A) might enter into a live donor paired exchange (LDPE) program with the hopes of swapping for a better-quality organ. A second patient (B) who is in the LDPE may or may not benefit from this exchange with Donor A. Methods: This medical decision analysis examines the conditions that favor Patient A entering into the LDPE compared to directly accepting a kidney from their intended donor, as well as the circumstances where Patient B also benefits by accepting a lower-quality organ. Results: Under select circumstances, a paired exchange could benefit both Patients A and B. For example, a 30-year-old Patient A with a lower-quality donor might gain 1.20 1.52 1.84 quality adjusted life years (QALYs) by entering into a LDPE for a better-quality kidney, whereas a 60-year-old Patient B might gain 0.93 1.03 1.13 QALYs by accepting Donor A’s kidney rather than waiting longer in the LDPE. The net benefit (or loss) of entering the LDPE differs by recipient age, donor organ quality, likelihood of Patient B being transplanted in LDPE, and likelihood of Patient A finding an ideal donor in the LDPE. Conclusion: This study shows there are ways to increase live donor utilization and effectiveness that require further research and potentially changes to the LDPE process.

Background. This is the first time deemed consent, where the entire population of a jurisdiction is considered to have consented for donation unless they have registered otherwise, will be implemented in North America. While relatively common in other regions of the world—notably Western Europe—it is uncertain how this practice will influence deceased donation practices and attitudes in Canada. Methods. We describe a Health Canada funded program of research that will evaluate the implementation process and full impact of the deceased organ donation legislation and the health system transformation in Nova Scotia that includes opt-out consent. Results. There is a need to evaluate the impact of these changes to inform not only Nova Scotia and Atlantic Canada, but also other provincial, national, and international stakeholders. Conclusions. We establish a rigorous academic framework that we will use to evaluate this significant health system transformation.

Background. The limited donor pool and increasing recipient wait list require a reevaluation of kidney organ suitability for transplantation. Use of higher infectious risk organs that were previously discarded may help improve access to transplantation and reduce patient mortality without placing patients at a higher risk of poor posttransplant outcomes. There is very little data available regarding the safe use of kidney organs from deceased donors with varicella zoster virus infection at the time of organ retrieval. Case Presentation. Here, we report a case of successful transplantation of both kidneys from a deceased donor with active herpes zoster infection at the time of organ retrieval. Recipients were treated preemptively with acyclovir. At 4 months posttransplant, both kidney recipients experienced no infectious complications and were off dialysis with functioning transplant grafts. Conclusions. The use of kidney organs from donors with active herpes zoster infection appears to be a safe option to expand the kidney donor pool.

Background: Long-duration (7-8 hours) hemodialysis provides benefits compared with conventional thrice-weekly, 4-hour sessions. Nurse-administered, in-center nocturnal hemodialysis (INHD) may expand the population to whom an intensive dialysis schedule can be offered. Objective: The primary objective of this study was to determine predictors of INHD technique failure, disruptions, and technique survival. Design: This study used retrospective chart and database review methodology. Setting: This study was conducted at a single Canadian INHD program operating in Victoria, British Columbia, within a tertiary care hospital. Our program serves a catchment population of approximately 450 000 people. Patients/Sample/Participants: Forty-three consecutive incident INHD patients took part in the INHD program of whom 42 provided informed consent to participate in this study. Methods: We conducted a retrospective observational study including incident INHD patients from 2015 to 2017. The primary outcome was technique failure ≤6 months (TF ≤6). Secondary outcomes included technique survival and reasons for/predictors of INHD discontinuation or temporary disruption. Predictors of each outcome included demographics, comorbidities, and Clinical Frailty Scale (CFS) scoring. Results: Among 42 patients, mean (SD) age, dialysis vintage, CFS score, and follow-up were 63 (16) years, 46 (55) months, 4 (1), and 11 (9) months, respectively. 52% were aged ≥65 years. TF ≤6 occurred in 12 (29%) patients. One-year technique survival censored for transplants and home dialysis transitions was 60%. Discontinuation related to insomnia (32%), medical status change (27%), and vascular access (23%). In unadjusted Cox survival analysis, 1-point increases in CFS score associated with a higher risk of technique failure (hazard ratio: 2.04, 95% confidence interval [CI]: 1.26-3.31). In an adjusted analysis, higher frailty severity also associated with temporary INHD disruptions (incidence rate ratio: 2.64, 95% CI: 1.55-4.50, comparing CFS of ≥4 to 1-3). Limitations: The retrospective, observational design of this study resulted in limited ability to control for confounding factors. In addition, the relatively small number of events observed owing to a small sample size diminished statistical power to inform study conclusions. Use of a single physician to determine the clinical frailty score is another limitation. Finally, the use of a single center for this study limits generalizability to other programs and clinic settings. Conclusions: INHD is a sustainable modality, even among older patients. Higher frailty associates with INHD technique failure and greater missed treatments. Inclusion of a CFS threshold of ≤4 into INHD inclusion criteria may help to identify individuals most likely to realize the long-term benefits of INHD. Trial Registration: Due to the retrospective and observational design of this study, trial registration was not necessary.

Purpose of review: Strategies to mitigate muscle cramps are a top research priority for patients receiving hemodialysis. As hypomagnesemia is a possible risk factor for cramping, we reviewed the literature to better understand the physiology of cramping as well as the epidemiology of hypomagnesemia and muscle cramps. We also sought to review the evidence from interventional studies on the effect of oral and dialysate magnesium-based therapies on muscle cramps. Sources of information: Peer-reviewed articles. Methods: We searched for relevant articles in major bibliographic databases including MEDLINE and EMBASE. The methodological quality of interventional studies was assessed using a modified version of the Downs and Blacks criteria checklist. Key findings: The etiology of muscle cramps in patients receiving hemodialysis is poorly understood and there are no clear evidence-based prevention or treatment strategies. Several factors may play a role including a low concentration of serum magnesium. The prevalence of hypomagnesemia (concentration of

Purpose: To collate best practice recommendations on the management of patients receiving in-center hemodialysis during the COVID-19 pandemic, based on published reports and current public health advice, while considering ethical principles and the unique circumstances of Canadian hemodialysis units across the country. Sources of information: The workgroup members used Internet search engines to retrieve documents from provincial and local hemodialysis programs; provincial public health agencies; the Centers for Disease Control and Prevention; webinars and slides from other kidney agencies; and nonreviewed preprints. PubMed was used to search for peer-reviewed published articles. Informal input was sought from knowledge users during a webinar. Methods: Challenges in the care of hemodialysis patients during the COVID-19 pandemic were highlighted within the Canadian Senior Renal Leaders Forum discussion group. The Canadian Society of Nephrology (CSN) developed the COVID-19 rapid response team (RRT) to address these challenges. They identified a pan-Canadian team of clinicians and administrators with expertise in hemodialysis to form the workgroup. One lead was chosen who drafted the initial document. Members of the workgroup reviewed and discussed all recommendations in detail during 2 virtual meetings on April 7 and April 9. Disagreements were resolved by consensus. The document was reviewed by the CSN COVID-19 RRT, an ethicist, an infection control expert, a community nephrologist, and a patient partner. Content was presented during an interactive webinar on April 11, 2020 attended by 269 kidney health professionals, and the webinar and first draft of the document were posted online. Final revisions were made based on feedback received until April 13, 2020. CJKHD editors reviewed the parallel process peer review and edited the manuscript for clarity. Key findings: Recommendations were made under the following themes: (1) Identification of patients with COVID-19 in the dialysis unit, (2) hemodialysis of patients with confirmed COVID-19, (3) hemodialysis of patients not yet known to have COVID-19, (4) visitors; (5) testing for COVID-19 in the dialysis unit; (6) resuscitation, (6) routine hemodialysis care, (7) hemodialysis care under fixed dialysis resources. Limitations: Because of limitations of time and resources, and the large number of questions, formal systematic review was not undertaken. The recommendations are based on expert opinion and subject to bias. The parallel review process that was created may not be as robust as the standard peer review process. Implications: We hope that these recommendations provide guidance for dialysis unit directors, clinicians, and administrators on how to limit risk from infection and adverse outcomes, while providing necessary dialysis care in a setting of finite resources. We also identify a number of resource allocation priorities, which we hope will inform decisions at provincial funding agencies.

Background: Understanding how frailty affects patients listed for transplantation has been identified as a priority research need. Frailty may be associated with a high risk of death or wait-list withdrawal, but this has not been evaluated in a large multicenter cohort of Canadian wait-listed patients. Objective: The primary objective is to evaluate whether frailty is associated with death or permanent withdrawal from the transplant wait list. Secondary objectives include assessing whether frailty is associated with hospitalization, quality of life, and the probability of being accepted to the wait list. Design: Prospective cohort study. Setting: Seven sites with established renal transplant programs that evaluate patients for the kidney transplant wait list. Patients: Individuals who are being considered for the kidney transplant wait list. Measurements: We will assess frailty using the Fried Phenotype, a frailty index, the Short Physical Performance Battery, and the Clinical Frailty Scale at the time of listing for transplantation. We will also assess frailty at the time of referral to the wait list and annually after listing in a subgroup of patients. Methods: The primary outcome of the composite of time to death or permanent wait-list withdrawal will be compared between patients who are frail and those who are not frail and will account for the competing risks of deceased and live donor transplantation. Secondary outcomes will include number of hospitalizations and length of stay, and in a subset, changes in frailty severity over time, change in quality of life, and the probability of being listed. Recruitment of 1165 patients will provide >80% power to identify a relative hazard of ≥1.7 comparing patients who are frail to those who are not frail for the primary outcome (2-sided α = .05), whereas a more conservative recruitment target of 624 patients will provide >80% power to identify a relative hazard of ≥2.0. Results: Through December 2019, 665 assessments of frailty (inclusive of those for the primary outcome and all secondary outcomes including repeated measures) have been completed. Limitations: There may be variation across sites in the processes of referral and listing for transplantation that will require consideration in the analysis and results. Conclusions: This study will provide a detailed understanding of the association between frailty and outcomes for wait-listed patients. Understanding this association is necessary before routinely measuring frailty as part of the wait-list eligibility assessment and prior to ascertaining the need for interventions that may modify frailty. Trial Registration: Not applicable as this is a protocol for a prospective observational study.

Abstract Background Frailty is associated with poor outcomes for patients on dialysis and is traditionally measured using tools that assess physical impairment. Alternate measurement tools highlight cognitive and functional domains, requiring clinician, patient, and/or caregiver input. In this study, we compared frailty measures for incident dialysis patients that incorporate patient, clinician, and caregiver perspectives with an aim to contrast the measured prevalence of frailty using tools derived from different conceptual frameworks. Methods A prospective cohort study of incident dialysis patients was conducted between February 2014 and June 2015. Frailty was assessed at dialysis onset using: 1) modified definition of Fried Phenotype (Dialysis Morbidity Mortality Study definition, DMMS); 2) Clinical Frailty Scale (CFS); 3) Frailty Assessment Care Planning Tool (provides CFS grading, FACT-CFS); and 4) Frailty Index (FI). Measures were compared via correlation and sensitivity/specificity analyses. Results A total of 98 patients participated (mean age of 61 ± 14 years). Participants were primarily Caucasian (91%), male (58%), and the majority started on hemodialysis (83%). The median score for both the CFS and FACT-CFS was 4 (interquartile range of 3–5). The mean FI score was 0.31 (standard deviation ± 0.16). The DMMS identified 78% of patients as frail. The FACT-CFS demonstrated highest correlation (r = 0.71) with the FI, while the DMMS was most sensitive (97%, 100%) and a CFS ≥ 5 most specific (100%, 77%) at corresponding FI cutoff values (>0.21, >0.45). Conclusions Frailty assessments of incident dialysis patients that include clinician, caregiver and patient perspectives have moderate to strong correlation with the FI. At specified FI cutoff values, the FACT-CFS and DMMS are highly sensitive measures of frailty. The CFS and FACT-CFS may represent viable alternative screening tools in dialysis patients.

Background: Dialysis patients have reduced moderate to vigorous physical activity, and light physical activity. This has been shown in self-reported surveys and objective accelerometer studies. Less attention has been directed toward sedentary behavior, which is characterized by low energy expenditure (≤1.5 metabolic equivalents). Furthermore, locations where physical activity and sedentary behavior occur are largely unknown for dialysis patients. Objectives: The objectives of this study were (1) to determine the minutes per day of moderate to vigorous physical activity, light physical activity, and sedentary behavior for hemodialysis patients; (2) to describe differences in moderate to vigorous physical activity, light physical activity, and sedentary behavior comparing dialysis versus nondialysis days; and (3) to describe the locations where moderate to vigorous physical activity, light physical activity, and sedentary behavior occur using global positioning system (GPS) data. Design: Cross-sectional study. Setting: The study was performed at a tertiary care hospital in Nova Scotia, Canada. Patients: A total of 50 adult in-center hemodialysis patients consented to the study. Measurements: Physical activity and sedentary behavior were measured with an Actigraph-GT3X accelerometer. Location was determined using a Qstarz BT-Q1000X GPS receiver. Methods: Minutes of daily activity were described as was percentage of wear time for each activity level across different locations during waking hours. Physical activity intensity, quantity, and location were also analyzed according to dialysis vs nondialysis days. Results: Forty-three patients met requirements for accelerometer analysis, of whom 42 had GPS data. Median wear time was 836.5 min/day (interquartile range [IQR]: 788.3-918.3). Median minutes of daily wear time spent in sedentary behavior, light physical activity, and moderate to vigorous physical activity was 636 minutes (IQR: 594.1-730.1), 178 minutes (IQR: 144-222.1), and 1.6 minutes (IQR: 0.6-7.7), respectively. Proportion of daily wear time spent in sedentary behavior, light physical activity, and moderate to vigorous physical activity was 78.4% (IQR: 70.7-84.0), 21.5% (IQR: 16.0-26.9), and 0.2% (IQR: 0.1-1.1), respectively. Home was the dominant location for total linked accelerometer-GPS time (59.4%, IQR: 46.9-69.5) as well as for each prespecified level of activity. Significantly more sedentary behavior and less light physical activity occurred on dialysis days compared with nondialysis days ( P ≤ .01, respectively). Moderate to vigorous physical activity did not differ significantly between dialysis and nondialysis days. Limitations: Small sample size from a single academic center may limit generalizability. Difficult to engage population as less than half of eligible dialysis patients provided consent. Physical activity may have been underestimated as devices were not worn for all waking hours or aquatic activities, and hip-based accelerometers may not capture stationary exercise. Conclusions: Ambulatory, in-center hemodialysis patients exhibit substantial sedentary behavior and minimal physical activity across a limited range of locations. Given the sedentary tendencies of this population, focus should be directed on increasing physical activity at any location frequented. Home-based exercise programs may serve as a potential adjunct to established intradialytic-based therapies given the amount of time spent in the home environment.

Purpose of review: Many observational studies have demonstrated a survival benefit with home dialysis compared with in-center dialysis; however, results have been conflicting. The purpose of this review was to identify pitfalls and limitations in existing literature and examine the challenges of studying home and in-center dialysis populations. Sources of information: Original research articles were identified from MEDLINE using search terms “in-center hemodialysis,” “home hemodialysis,” “conventional hemodialysis,” “nocturnal hemodialysis,” and “short daily hemodialysis.” Methods: A focused review and critical appraisal of existing home versus in-center hemodialysis survival literature was conducted to identify potential causes for variability in the observed survival outcomes. Key findings: The controversy in existing literature stems from the challenges of randomizing patients to home versus in-center hemodialysis modalities, and therefore a reliance on observational comparisons for study. In many cases, these observational analyses have been limited by selection bias (variabilities in populations included, inclusion of both incident and prevalent cohorts, and variabilities in dialysis intensity), as well as residual confounding. Furthermore, the studies that do exist lack generalizability in many cases. Limitations: There are few randomized controlled trials examining the survival benefit of home versus in-center hemodialysis and existing observational studies are often limited by bias and reduced generalizability. These limitations comprise the body of this review. Implications: This review examines challenges surrounding survival comparisons with home versus in-center hemodialysis and identify important directions for future study.

Background: Dialysis patients who require ambulance transport to the emergency department (“ambulance-ED”) may subsequently require timely dialysis in a monitored setting (“urgent dialysis”). Objective: The purpose of this study was to develop and internally validate a risk prediction model for urgent dialysis based on patient characteristics at the time of paramedic assessment before ambulance-ED. Design: Cohort Study Setting: Region of Nova Scotia, Canada, covered by a single emergency medical services provider Patients: Thrice-weekly hemodialysis patients who initiated dialysis between 2009 and 2013 (follow-up to 2015) and experienced one or more ambulance-ED events. Measurements: The primary outcome (“urgent dialysis”) was defined as dialysis within 24 hours of an ambulance-ED in a monitored setting or dialysis within 24 hours of an ambulance-ED with an initial ED potassium of >6.5 mmol/L. Predictors of urgent dialysis based on paramedic assessment before ambulance-ED included presenting complaint, vital signs and time from last dialysis to ambulance dispatch. Methods: Associations with urgent dialysis were analyzed using logistic regression from which a risk prediction model was created. The model was internally validated using bootstrapping and model performance was assessed by discrimination and calibration. Results: Among 197 patients, there were 624 ambulance-ED events and 87 episodes of urgent dialysis. Weakness as a presenting complaint (odds ratio [OR]: 4.62, 95% confidence interval [CI]: 1.23-17.29), >24 hours since last dialysis (OR: 2.09, 95% CI: 1.15-3.81), and vital signs, including heart rate 160 mmHg, were associated with urgent dialysis after ambulance-ED. A risk prediction model incorporating these variables had very good discrimination (C-statistic: 0.81, 95% CI: 0.76-0.86). The negative predictive value was 93.6% using the optimal cut point. Of patients who were predicted to need urgent dialysis but were transported to a facility incapable of providing it, 31% were re-transported for urgent dialysis. Limitations: Findings of our study may not be generalizable to other centers where the practice of ambulance transfer and availability of monitored dialysis may differ, and data were lacking for potential missed dialysis sessions or changes in routine dialysis scheduling. Conclusions: Patient characteristics at the time of paramedic assessment are associated with urgent dialysis after ambulance-ED. This risk prediction model has the potential to guide dialysis patient transport to dialysis-capable facilities when needed.

Background. In kidney transplantation, nonimmunologic donor-recipient (D-R) pairing is generally not given the same consideration as immunologic matching. The aim of this study was to determine how nonimmunologic D-R pairing relates to independent donor and recipient factors, and to immunologic HLA match for predicting graft loss. Methods. Seven D-R pairings (race, sex, age, weight, height, cytomegalovirus serostatus, and HLA match) were assessed for their association with the composite outcome of death or kidney graft loss using a Cox regression-based forward stepwise selection model. The best model for predicting graft loss (including nonimmunologic D-R pairings, independent D-R factors, and/or HLA match status) was determined using the Akaike Information Criterion. Results. Twenty three thousand two hundred sixty two (29.9%) people in the derivation data set and 9892 (29.7%) in the validation data set developed the composite outcome of death or graft loss. A model that included both independent and D-R pairing variables best predicted graft loss. The c-indices for the derivation and validation models were 0.626 and 0.629, respectively. Size mismatch (MM) between donor and recipient (>30 kg [D < R} and >15 cm [D < R]) was associated with poor patient and graft survival even with 0 HLA MM, and conversely, an optimal D-R size pairing mitigated the risk of graft loss seen with 6 HLA MM. Conclusions. D-R pairing is valuable in predicting patient and graft outcomes after kidney transplant. D-R size matching could offset the benefit and harm seen with 0 and 6 HLA MM, respectively. This is a novel finding.