The Preserving Kidney Function in Children With CKD (PRESERVE) Study: Rationale, Design, and Methods

Rationale & Objective

PRESERVE seeks to provide new knowledge to inform shared decision-making regarding blood pressure (BP) management for pediatric chronic kidney disease (CKD). PRESERVE will compare the effectiveness of alternative strategies for monitoring and treating hypertension on preserving kidney function; expand the National Patient-Centered Clinical Research Network (PCORnet) common data model by adding pediatric- and kidney-specific variables and linking electronic health record data to other kidney disease databases; and assess the lived experiences of patients related to BP management.

Study Design

Multicenter retrospective cohort study (clinical outcomes) and cross-sectional study (patient-reported outcomes [PROs]).

Setting & Participants

PRESERVE will include approximately 20,000 children between January 2009-December 2022 with mild-moderate CKD from 15 health care institutions that participate in 6 PCORnet Clinical Research Networks (PEDSnet, STAR, GPC, PaTH, CAPRiCORN, and OneFlorida+). The inclusion criteria were ≥1 nephrologist visit and ≥2 estimated glomerular filtration rate (eGFR) values in the range of 30 to <90 mL/min/1.73 m2 separated by ≥90 days without an intervening value ≥90 mL/min/1.73 m2 and no prior dialysis or kidney transplant.

Exposures

BP measurements (clinic-based and 24-hour ambulatory BP); urine protein; and antihypertensive treatment by therapeutic class.

Outcomes

The primary outcome is a composite event of a 50% reduction in eGFR, eGFR of <15 mL/min/1.73 m2, long-term dialysis or kidney transplant. Secondary outcomes include change in eGFR, adverse events, and PROs.

Analytical Approach

Longitudinal models for dichotomous (proportional hazards or accelerated failure time) and continuous (generalized linear mixed models) clinical outcomes; multivariable linear regression for PROs. We will evaluate heterogeneity of treatment effect by CKD etiology and degree of proteinuria and will examine variation in hypertension management and outcomes based on socio-demographics.

Limitations

Causal inference limited by observational analyses.

Conclusions

PRESERVE will leverage the PCORnet infrastructure to conduct large-scale observational studies that address BP management knowledge gaps for pediatric CKD, focusing on outcomes that are meaningful to patients.

Plain-Language Summary

Hypertension is a major modifiable contributor to loss of kidney function in chronic kidney disease (CKD). The purpose of PRESERVE is to provide evidence to inform shared decision-making regarding blood pressure management for children with CKD. PRESERVE is a consortium of 16 health care institutions in PCORnet, the National Patient-Centered Clinical Research Network, and includes electronic health record data for >19,000 children with CKD. PRESERVE will (1) expand the PCORnet infrastructure for research in pediatric CKD by adding kidney-specific variables and linking electronic health record data to other kidney disease databases; (2) compare the effectiveness of alternative strategies for monitoring and treating hypertension on preserving kidney function; and (3) assess the lived experiences of patients and caregivers related to blood pressure management.

Patient-Reported Outcomes Over 24 Months in Pediatric CKD: Findings From the MyKidneyHealth Cohort Study

RATIONALE & OBJECTIVE

The lived experience of children with chronic kidney disease (CKD) is poorly characterized. We examined the associations between patient-reported outcome (PRO) scores measuring their fatigue, sleep health, psychological distress, family relationships, and global health with clinical outcomes over time in children, adolescents, and younger adults with CKD and investigated how the PRO scores of this group compare with those of other children, adolescents, and younger adults.

STUDY DESIGN

Prospective cohort study.

SETTING & PARTICIPANTS

212 children, adolescentss, and adults aged 8 to 21 years with CKD and their parents recruited from 16 nephrology programs across North America.

PREDICTORS

CKD stage, disease etiology, and sociodemographic and clinical variables.

OUTCOME

PRO scores over 2 years.

ANALYTICAL APPROACH

We compared PRO scores in the CKD sample with a nationally representative general pediatric population (ages 8 to 17 years). Change of PROs over time and association of sociodemographic and clinical variables with PROs were assessed using multivariable regression models.

RESULTS

For all time points, 84% of the parents and 77% of the children, adolescents, and younger adults completed PRO surveys . The baseline PRO scores for the participants with CKD revealed a higher burden of fatigue, sleep-related impairment, psychological distress, impaired global health, and poorer family relationships compared with the general pediatric population, with median score differences≥1 SD for fatigue and global health. The baseline PRO scores did not differ by CKD stage or glomerular versus nonglomerular etiology. Over 2 years, PROs were stable with a<1-point annual change on average on each measure and intraclass correlation coefficients ranging from 0.53 to 0.79, indicating high stability. Hospitalization and parent-reported sleep problems were associated with worse fatigue, psychological health, and global health scores (all P<0.04).

LIMITATIONS

We were unable to assess responsiveness to change with dialysis or transplant.

CONCLUSIONS

Children with CKD experience a high yet stable burden of impairment across numerous PRO measures, especially fatigue and global health, independent of disease severity. These findings underscore the importance of assessing PROs, including fatigue and sleep measures, in this vulnerable population.

PLAIN-LANGUAGE SUMMARY

Children with chronic kidney disease (CKD) have many treatment demands and experience many systemic effects. How CKD impacts the daily life of a child is poorly understood. We surveyed 212 children, adolescents, and younger adults with CKD and their parents over 24 months to assess the participants' well-being over time. Among children, adolescents, and younger adults with CKD we found a very high and persistent burden of psychological distress that did not differ by degree of CKD or type of kidney disease. The participants with CKD endorsed greater impairment in fatigue and global health compared with healthy children, adolescents, and younger adults, and parent-reported sleep problems were associated with poorer patient-reported outcome (PRO) scores across all domains. These findings emphasize the importance of including PRO measures, including fatigue and sleep measures, into routine clinical care to optimize the lived experience of children with CKD.

Psychosocial supports within pediatric nephrology practices: A pediatric nephrology research consortium survey

BACKGROUND

The landscape of available psychosocial services within pediatric nephrology care is poorly characterized. However, the effects of kidney disease on emotional health and health-related quality of life are well documented, as is the impact of social determinants of health on kidney disease outcomes. The objectives of this study were to assess pediatric nephrologists' perceptions of available psychosocial services and to elucidate inequities in access to psychosocial care.

METHODS

A web-based survey was distributed to members of the Pediatric Nephrology Research Consortium (PNRC). Quantitative analyses were performed.

RESULTS

We received responses from 49 of the 90 PNRC centers. With regards to dedicated services, social work was most commonly available (45.5-100%), followed by pediatric psychology (0-57.1%) and neuropsychology (0-14.3%), with no centers having embedded psychiatry. Availability of psychosocial providers was positively associated with nephrology division size, such that as center size increased, access to various psychosocial providers increased. Notably, the majority of respondents indicated that perceived need for psychosocial support exceeds that which is currently available, even at centers with higher levels of current support.

CONCLUSIONS

Within the US, there is wide variability in the availability of psychosocial services within pediatric nephrology centers despite a well-documented necessity for the provision of holistic care. Much work remains to better understand the variation in funding for psychosocial services and in utilization of psychosocial professionals in the pediatric nephrology clinic, and to inform key best practices for addressing the psychosocial needs of patients with kidney disease.

Food insecurity during COVID-19 in children with end-stage kidney disease: a pilot study

BACKGROUND

Food insecurity, an important social determinant of health among children, has become more common during the COVID-19 pandemic. Children with chronic diseases including end-stage kidney disease (ESKD) are at higher risk of food insecurity due to their complex care needs, medication burden, and dietary restrictions. No data exists describing food insecurity prevalence in pediatric ESKD patients during the COVID-19 pandemic.

METHODS

Food insecurity was assessed among families of children (age 0-18 years) with ESKD on chronic dialysis at two pediatric academic medical centers. Families were screened in April 2020 using the Hunger Vital Sign, a validated 2-question screening tool. We assessed impact of COVID-19 on food insecurity. We compared serum phosphorus "pre-COVID" (January/February 2020) to "during COVID" (April/May 2020).

RESULTS

A total of 29 families enrolled in this study. 62% (18/29) of children with ESKD lived in food insecure households, and of those, 72% (13/18) reported that COVID-19 had worsened their food insecurity status. During the COVID-19 pandemic, food insecure patients experienced greater rise in their serum phosphorus levels (1.1 mg/dL vs. 0 mg/dL, p = 0.03) and decreased likelihood of having adequate phosphorus control (50% vs. 11%, p = 0.03).

CONCLUSION

Food insecurity was common among children with ESKD on chronic dialysis during the COVID-19 pandemic. Children with food insecurity had a greater increase in their phosphorus levels during the pandemic than did food secure children. Further exploration into how food resources such as an onsite food pantry impacts food insecurity and phosphorus control in children with ESKD is essential.

Association Between Continuous Kidney Replacement Therapy Clearance and Outcome in Pediatric Patients With Hyperammonemia Not Due to Inborn Error of Metabolism

OBJECTIVES

To describe a single-center experience of pediatric patients with hyperammonemia not due to inborn errors of metabolism and determine the association between use of continuous kidney replacement therapy (CKRT) treatment and outcomes.

DESIGN

Retrospective cohort study.

SETTING

Tertiary-care children's hospital.

PATIENTS

All children less than 21 years old admitted to the hospital with hyperammonemia defined as an elevated ammonia levels (>100 µmol/L) not due to inborn error of metabolism.

INTERVENTIONS

None.

MEASURES AND MAIN RESULTS

Of 135 children with hyperammonemia, the most common reason for admission was infection in 57 of 135 (42%), congenital heart disease in 20 of 135 (14%), and bone marrow transplantation in 10 of 135 (7%). The overall mortality was 61% (82 of 135), which increased with degree of hyperammonemia (17 of 23 [74%] in those with ammonia >250 µmol/L). After multivariable regression, hyperammonemia severity was not associated with mortality (aOR, 1.4; 95% CI, 0.92-2.1; p = 0.11). Of the 43 patients (32%) receiving CKRT, 21 were prescribed standard clearance and 22 high clearance. The most common indications for CKRT were fluid overload in 17 of 43 (42%) and acute kidney injury or uremia in 16 of 43 (37%). Mean CKRT duration was 13 days. There was no difference between standard and high clearance groups in risk of death (76% vs 86%; p = 0.39), cerebral edema on CT scan (19% vs 27%; p = 0.52), nor decrease in ammonia levels after 24 or 48 hours of CKRT ( p = 0.20, p = 0.94). Among those receiving CKRT, we failed to find an association between high clearance and decreased risk of death in multivariable analysis (aOR, 1.2; 95% CI, 0.64-2.3; p = 0.55).

CONCLUSIONS

In our single-center retrospective study, we failed to find an association between clearance on CKRT and improved survival nor decreased cerebral edema on head imaging. In fact, we failed to find an association between ammonia level and mortality, after controlling for illness severity.

Food Insecurity During COVID-19 in Children with End-Stage Kidney Disease: A Pilot Study.. [PMID: 35378760 PMCID: PMC8978953 DOI: 10.21203/rs.3.rs-910466/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

Background

Food insecurity, an important social determinant of health among children, has become more common during the COVID-19 pandemic. Children with chronic diseases including end-stage kidney disease (ESKD) are at higher risk of food insecurity due to their complex care needs, medication burden, and dietary restrictions. No data exists describing food insecurity prevalence in pediatric ESKD patients during the COVID-19 pandemic.

Methods

Food insecurity was assessed among families of children (age 0–18 years) with ESKD on chronic dialysis at two pediatric academic medical centers. Families were screened in April 2020 using the Hunger Vital Sign, a validated 2-question screening tool. We assessed impact of COVID-19 on food insecurity. We compared serum phosphorus “pre-COVID” (January/February 2020) to “during COVID” (April/May 2020).

Results

A total of 29 families enrolled in this study. 62% (18/29) of children with ESKD lived in food insecure households, and of those, 72% (13/18) reported that COVID-19 had worsened their food insecurity status. During the COVID-19 pandemic, food insecure patients experienced greater rise in their serum phosphorus levels (p=0.03) and decreased likelihood of having adequate phosphorus control (p=0.03).

Conclusion

Food insecurity was common among children with ESKD on chronic dialysis during the COVID-19 pandemic. Children with food insecurity had a greater increase in their phosphorus levels during the pandemic than did food secure children. Further exploration into how food resources such as an onsite food pantry impacts food insecurity and phosphorus control in children with ESKD is essential.

Systemic Hypertension in Infants with Bronchopulmonary Dysplasia

PURPOSE OF REVIEW

Neonatal hypertension is increasingly recognized as improvements in neonatal intensive care have led to increased survival of premature infants. Among infants with bronchopulmonary dysplasia (BPD), the rates of hypertension are much higher than the general neonatal population. However, the etiology and pathophysiology of this increased risk of hypertension in neonates with lung disease remain unclear.

RECENT FINDINGS

Among infants with bronchopulmonary dysplasia, the rates of hypertension are much higher than the general neonatal population. New studies suggest outcomes in neonates with BPD with hypertension are usually good, with resolution of hypertension in most infants with lung disease. Several potential mechanisms of hypertension in this patient population have been recently proposed. This review focuses on the recent epidemiologic data on prevalence of hypertension in neonates with bronchopulmonary dysplasia, reviews the typical clinical course, and discusses available strategies for management of infants with bronchopulmonary dysplasia that develop hypertension.

High-fidelity laser-free universal control of trapped ion qubits

Universal control of multiple qubits-the ability to entangle qubits and to perform arbitrary individual qubit operations¹-is a fundamental resource for quantum computing², simulation³ and networking⁴. Qubits realized in trapped atomic ions have shown the highest-fidelity two-qubit entangling operations^5-7 and single-qubit rotations⁸ so far. Universal control of trapped ion qubits has been separately demonstrated using tightly focused laser beams^9-12 or by moving ions with respect to laser beams^13-15, but at lower fidelities. Laser-free entangling methods^16-20 may offer improved scalability by harnessing microwave technology developed for wireless communications, but so far their performance has lagged the best reported laser-based approaches. Here we demonstrate high-fidelity laser-free universal control of two trapped-ion qubits by creating both symmetric and antisymmetric maximally entangled states with fidelities of [Formula: see text] and [Formula: see text], respectively (68 per cent confidence level), corrected for initialization error. We use a scheme based on radiofrequency magnetic field gradients combined with microwave magnetic fields that is robust against multiple sources of decoherence and usable with essentially any trapped ion species. The scheme has the potential to perform simultaneous entangling operations on multiple pairs of ions in a large-scale trapped-ion quantum processor without increasing control signal power or complexity. Combining this technology with low-power laser light delivered via trap-integrated photonics^21,22 and trap-integrated photon detectors for qubit readout^23,24 provides an opportunity for scalable, high-fidelity, fully chip-integrated trapped-ion quantum computing.

State Readout of a Trapped Ion Qubit Using a Trap-Integrated Superconducting Photon Detector

We report high-fidelity state readout of a trapped ion qubit using a trap-integrated photon detector. We determine the hyperfine qubit state of a single ^{9}Be^{+} ion held in a surface-electrode rf ion trap by counting state-dependent ion fluorescence photons with a superconducting nanowire single-photon detector fabricated into the trap structure. The average readout fidelity is 0.9991(1), with a mean readout duration of 46  μs, and is limited by the polarization impurity of the readout laser beam and by off-resonant optical pumping. Because there are no intervening optical elements between the ion and the detector, we can use the ion fluorescence as a self-calibrated photon source to determine the detector quantum efficiency and its dependence on photon incidence angle and polarization.

Judging meaning: A domain-level difference between autistic and non-autistic adults

We tested whether autistic adults would show selective difficulties across several tests of inferencing and social understanding in the context of average-range core language ability. One-hundred and ninety-one participants completed an online battery, and data were analysed using confirmatory factor analysis. Results showed that vocabulary knowledge was separate from other measures, which collectively formed a 'receptive communication' factor. Autistic people underperformed on the 'receptive communication' factor but showed more advanced vocabulary knowledge than non-autistic participants. Lower performance among autistic adults on the test battery predicted face-to-face communication difficulties measured by self-report and researcher ratings, with moderate effect sizes. Follow-up analysis indicated three further findings. We hypothesized that differences would arise from an isolated 'theory of mind' difficulty in autistic people, but instead the data suggested more general information-processing differences when making judgements about communicative stimuli. Second, substantial group differences on a test of implied meaning were only partly explained at the factor level, suggesting that multiple cognitive influences underpinned these differences. Finally, autistic women tended to perform better than autistic men. Our results support the idea of a subtle domain-level difference in pragmatics in autistic people, while questioning the basis of this difference and highlighting substantial variability in skills across groups.

Coronavirus disease 2019 (COVID-19) in two pediatric patients with kidney disease on chronic immunosuppression: A case series

Coronavirus disease 2019 (COVID‐19) is a highly infectious disease caused by the severe acute respiratory syndrome coronavirus 2 virus (SARS‐CoV‐2). While children appear to experience less severe disease than adults, those with underlying conditions such as kidney disease may be more susceptible to infection. Limited data are present for children with kidney disease, and there are limited prior reports of pediatric hemodialysis patients with COVID‐19. This report describes the mild clinical disease course of COVID‐19 in two pediatric patients with chronic kidney disease, one on hemodialysis and both on chronic immunosuppression. We review treatment in these patients, as well as our measures to reduce transmission among our hemodialysis patients and staff.

Adiposity, Sex, and Cardiovascular Disease Risk in Children With CKD: A Longitudinal Study of Youth Enrolled in the Chronic Kidney Disease in Children (CKiD) Study

RATIONALE & OBJECTIVE

Traditional and nontraditional cardiovascular disease risk factors are highly prevalent in children with chronic kidney disease (CKD). We examined the longitudinal association of adiposity with cardiac damage among children with CKD and explored whether this association was modified by sex.

STUDY DESIGN

Prospective cohort study.

SETTING & PARTICIPANTS

Children with mild-to-moderate CKD enrolled in the Chronic Kidney Disease in Children (CKiD) Study at 49 pediatric nephrology centers across North America.

EXPOSURE

Age- and sex-specific body mass index (BMI) z score.

OUTCOME

Age- and sex-specific left ventricular mass index (LVMI) z score and left ventricular hypertrophy (LVH).

ANALYTICAL APPROACH

Longitudinal analyses using mixed-effects models to estimate sex-specific associations of BMI z scores with LVMI z score and with LVH, accounting for repeated measurements over time.

RESULTS

Among 725 children with 2,829 person-years of follow-up, median age was 11.0 years and median estimated glomerular filtration rate was 52.6mL/min/1.73m2. Nearly one-third of both boys and girls were overweight or obese, median LVMI z score was 0.18 (IQR: -0.67, 1.08), and 11% had LVH. Greater BMI z scores were independently associated with greater LVMI z scores and greater odds of LVH. For each 1-unit higher BMI z score, LVMI z score was 0.24 (95% CI, 0.17-0.31) higher in boys and 0.38 (95% CI, 0.29-0.47) higher in girls (Pinteraction = 0.01). For each 1-unit higher BMI z score, the odds of LVH was 1.5-fold (95% CI, 1.1-2.1) higher in boys and 3.1-fold (95% CI, 1.8-4.4) higher in girls (Pinteraction = 0.005).

LIMITATIONS

Not all children had repeated measurements. LVH is a surrogate and not a hard cardiac outcome. The observational design limits causal inference.

CONCLUSIONS

In children, adiposity is independently associated with the markers of cardiac damage, LVMI z score and LVH. This association is stronger among girls than boys. Pediatric overweight and obesity may therefore have a substantial impact on cardiovascular risk among children with CKD.

The Improving Renal Outcomes Collaborative: Blood Pressure Measurement in Transplant Recipients

BACKGROUND AND OBJECTIVES

Hypertension is highly prevalent in pediatric kidney transplant recipients and contributes to cardiovascular death and graft loss. Improper blood pressure (BP) measurement limits the ability to control hypertension in this population. Here, we report multicenter efforts from the Improving Renal Outcomes Collaborative (IROC) to standardize and improve appropriate BP measurement in transplant patients.

METHODS

Seventeen centers participated in structured quality improvement activities facilitated by IROC, including formal training in quality improvement methods. The primary outcome measure was the proportion of transplant clinic visits with appropriate BP measurement according to published guidelines. Prospective data were analyzed over a 12-week pre-intervention period and a 20-week active intervention period for each center and then aggregated as of the program-specific start date. We used control charts to quantify improvements across IROC centers. We applied thematic analysis to identify patterns and common themes of successful interventions.

RESULTS

We analyzed data from 5392 clinic visits. At baseline, BP was measured and documented appropriately at 11% of visits. Center-specific interventions for improving BP measurement included educating clinic staff, assigning specific team member roles, and creating BP tracking tools and alerts. Appropriate BP measurement improved throughout the 20-week active intervention period to 78% of visits.

CONCLUSIONS

We standardized appropriate BP measurement across 17 pediatric transplant centers using the infrastructure of the IROC learning health system and substantially improved the rate of appropriate measurement over 20 weeks. Accurate BP assessment will allow further interventions to reduce complications of hypertension in pediatric kidney transplant recipients.

Blood pressure in children with chronic kidney disease: lessons learned from the Chronic Kidney Disease in Children Cohort Study

Cardiovascular disease (CVD) is common among children and adolescents with chronic kidney disease (CKD) and end-stage kidney disease (ESRD). However, the early accrual of CVD risk factors in children with CKD has not been well studied. The Chronic Kidney Disease in Children (CKiD) Study, a multicenter, prospective cohort study of children with mild-to-moderate CKD at study entry counts among its primary aims investigation of the drivers of CVD risk in this population. As the most prevalent CVD risk factor in children with CKD, blood pressure (BP) has been a major focus of investigation for the CKiD Study Group. Over the first 15 years of the study, landmark publications have better defined the prevalence of hypertension, the frequency with which it is under-recognized and thus undertreated, and the consequences of elevated BP in this cohort. The purpose of this review is to summarize the contributions made by the CKiD Study in advancing knowledge of BP in this high-risk population, and to highlight areas in need of further study.

Asymptomatic Seroconversion of Immunoglobulins to SARS-CoV-2 in a Pediatric Dialysis Unit

This case series describes subclinical development of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies in some patients and health care workers in a pediatric dialysis unit after contact with a seropositive patient.

Assessment of Seroconversion to SARS-CoV-2 in a Cohort of Pediatric Kidney Transplant Recipients

Background: The occurrence of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the associated coronavirus disease 2019 (COVID-19) have profoundly affected adult kidney disease patients. In contrast, pediatric solid organ transplant recipients, including pediatric kidney transplant (KT) recipients, do not seem to be at particularly higher risk for SARS-CoV-2 infection or for severe COVID-19 disease. This patient population might be protected by certain mechanisms, such as the immunosuppressive medications with their anti-inflammatory properties or simply being well-versed in self-protection techniques. Assessing SARS-CoV-2 antibody serologies could potentially help understand why this patient population is apparently spared from severe SARS-CoV-2 clinical courses. Objective: To examine SARS-CoV-2 serologic status in a cohort of pediatric KT recipients. Methods: SARS-CoV-2 anti-spike IgG and IgM antibodies were measured by three different methods in pediatric KT recipients coming for routine clinic visits immediately post-confinement in May-June of 2020. The patients were considered seroconverted if SARS-CoV-2 antibodies were positive by 2/3 methods and weak positive/indeterminate if positive by 1/3. Results: Thirty-one patients were evaluated (about 1/3 of our institution's pediatric KT population). One patient seroconverted, while three were considered weak positive/indeterminate. None were symptomatic and none had nasopharyngeal PCR confirmed SARS-CoV-2 disease. Conclusions: Seroconversion to SARS-CoV-2 was rare in this population and likely reflects the social distancing practiced by these patients. The results will serve as a foundation for a future longitudinal study to evaluate the long-term emergence and persistence of antibodies in this population and may inform studies of response to a future vaccine.

Versatile laser-free trapped-ion entangling gates

We present a general theory for laser-free entangling gates with trapped-ion hyperfine qubits, using either static or oscillating magnetic-field gradients combined with a pair of uniform microwave fields symmetrically detuned about the qubit frequency. By transforming into a 'bichromatic' interaction picture, we show that eitherσ ^ ϕ ⊗ σ ^ ϕ orσ ^ z ⊗ σ ^ z geometric phase gates can be performed. The gate basis is determined by selecting the microwave detuning. The driving parameters can be tuned to provide intrinsic dynamical decoupling from qubit frequency fluctuations. Theσ ^ z ⊗ σ ^ z gates can be implemented in a novel manner which eases experimental constraints. We present numerical simulations of gate fidelities assuming realistic parameters.

Practice Variation in the Immediate Postoperative Care of Pediatric Kidney Transplantation: A National Survey

INTRODUCTION

Advances in organ allocation, surgical technique, immunosuppression, and long-term follow-up have led to a significant improvement in kidney transplant outcomes. Although there are clear recommendations for several aspects of kidney transplant management, there are no pediatric-specific guidelines for immediate postoperative care. The aim of this survey is to examine practice variations in the immediate postoperative care of pediatric kidney transplant patients.

METHODS

We surveyed medical directors of Pediatric Acute Lung Injury and Sepsis Investigators (PALISI)-affiliated pediatric intensive care units regarding center-specific immediate postoperative management of pediatric kidney transplantation.

RESULTS

The majority of PALISI centers admit patients to the pediatric intensive care unit postoperatively, and 97% of the centers involve a pediatric nephrologist in immediate postoperative care. Most patients undergo invasive hemodynamic monitoring; 97% of centers monitor invasive arterial blood pressure and 88% monitor central venous pressure. Most centers monitor serum electrolytes every 4 to 6 hours. Wide variation exists regarding blood pressure goal, fluid replacement type, frequency of obtaining kidney ultrasound, and use of prophylactic anticoagulation.

CONCLUSION

There is consistent practice across PALISI centers in regards to many aspects of immediate postoperative management of pediatric kidney transplantation. However, variation still exists in some management aspects that warrant further discussions to reach a national consensus.

The addition of tick-boxes related to tobacco cessation improves smoking-related documentation in the anaesthesia chart

The Australian and New Zealand College of Anaesthetists (ANZCA) 'Guidelines on Smoking as Related to the Perioperative Period (PS12)' recommends that anaesthetists should always ask about smoking, advise quitting and refer patients to their general practitioner (GP) or a telephone quit-line for quit support. In this study we evaluated the effect of adding tick-boxes for 'quit advice given' and 'referral to GP/Quitline' to anaesthesia charts of elective surgical patients to assess whether this intervention changed documentation of compliance with the ANZCA guideline. The anaesthesia charts of all smokers were reviewed for evidence of asking, advising and referring, over two three-month periods (n=999) separated by the intervention of placing a sticker to modify the preoperative charts of all elective patients which added tick-box prompts of advice and referral. No educational campaigns occurred to encourage tick-box use. No changes were made to non-elective charts. Evidence of advice to quit was 1.8% prior to, rising to 18.7% after, the intervention (P <0.001), while evidence of referral rose from 0.9% to 5.8%. There was negligible change in non-elective patients, who did not receive the intervention. The addition of tick-boxes improved the documentation of smoking cessation support, but as documented rates of quit support remained relatively low even after the intervention, tick-boxes alone cannot be relied upon to improve alignment of care with the ANZCA guidelines.

Post-traumatic stress symptoms in children and adolescents with chronic pain: A topical review of the literature and a proposed framework for future research

BACKGROUND AND OBJECTIVE

The co-occurrence of chronic pain and post-traumatic stress symptoms (PTSS) and post-traumatic stress disorder (PTSD) has gained increasing research attention. Studies on associations among pain and PTSS or PTSD in youth have largely been conducted in the context of acute injury or trauma. Less is known about the risk for co-occurrence with paediatric chronic pain. In this review, we (1) propose a conceptual framework to outline factors salient during childhood that may be associated with symptom severity, co-occurrence and mutual maintenance, (2) present relevant literature on PTSS in youth with acute and chronic pain and identify research gaps and (3) provide recommendations to guide paediatric research examining shared symptomatology.

DATABASES AND DATA TREATMENT

Electronic databases (PubMed and Google Scholar) were used to identify relevant articles using the search terms 'child, adolescent, paediatric, chronic pain, acute pain, post-traumatic stress symptoms and post-traumatic stress disorder'. Studies were retrieved and reviewed based on relevance to the topic.

RESULTS

Our findings revealed that existing biobehavioural and ecological models of paediatric chronic pain lack attention to traumatic events or the potential development of PTSS. Paediatric studies are also limited by lack of a conceptual framework for understanding the prevalence, risk and trajectories of PTSS in youth with chronic pain.

CONCLUSIONS

Our new developmentally informed framework highlights individual symptoms and shared contextual factors that are important when examining potential associations among paediatric chronic pain and PTSS. Future studies should consider bidirectional and mutually maintaining associations, which will be aided by prospective, longitudinal designs. WHAT DOES THIS REVIEW ADD?: This review presents relevant literature on pain and PTSS in youth and proposes a conceptual framework to examine factors salient during childhood that may be associated with symptom severity, comorbidity and mutual maintenance of chronic pain and PTSS in paediatric populations. We highlight dynamic factors that may change across children's development and provide recommendations to guide paediatric research examining potential associations among PTSS and chronic pain.

Pharmacologic Management of Pediatric Hypertension

Hypertension in children is common, and the prevalence of primary hypertension is increasing with the obesity epidemic and changing dietary choices. Careful measurement of blood pressure is important to correctly diagnose hypertension, as many factors can lead to inaccurate blood pressure measurement. Hypertension is diagnosed based on comparison of age-, sex-, and height-based norms with the average systolic and diastolic blood pressures on three separate occasions. In the absence of hypertensive target organ damage (TOD), stage I hypertension is managed first by diet and exercise, with the addition of drug therapy if this fails. First-line treatment of stage I hypertension with TOD and stage II hypertension includes both lifestyle changes and medications. First-line agents include angiotensin-converting enzyme (ACE) inhibitors, thiazide diuretics, and calcium-channel blockers. Hypertensive emergency with end-organ effects requires immediate modest blood pressure reduction to alleviate symptoms. This is usually accomplished with IV medications. Long-term reduction in blood pressure to normal levels is accomplished gradually. Specific medication choice for outpatient hypertension management is determined by the underlying cause of hypertension and the comparative adverse effect profiles, along with practical considerations such as cost and frequency of administration. Antihypertensive medication is initiated at a starting dose and can be gradually increased to effect. If ineffective at the recommended maximum dose, an additional medication with a complementary mechanism of action can be added.

Late-Occurring Vancomycin-Associated Acute Kidney Injury in Children Receiving Prolonged Therapy

Background: Acute kidney injury (AKI) in patients receiving vancomycin has been associated with trough concentrations ≥15 mg/L and longer therapy duration. The objective of this study was to determine the incidence and factors associated with late AKI in children receiving ≥8 days of vancomycin therapy. Methods: Children aged 30 days to 17 years who were admitted to our institution and received intravenous vancomycin for at least 8 days during January to December of 2007 and 2010 and had a suspected or proven gram-positive infection were included. Late AKI was categorized as AKI occurring after the first 7 days of therapy and within 48 hours following vancomycin discontinuation. The primary outcome was incidence of late AKI as determined by modified pRIFLE criteria. Results: One-hundred sixty-seven patients were included, with a median (interquartile range) age (years) and weight (kg) of 2 (1-7) and 12.5 (8.9-23.8). Late AKI was identified in 12.6% (21/167). A higher percentage of late AKI patients received concomitant treatment with intravenous acyclovir, amphotericin products, or piperacillin-tazobactam. Age <1 year was the only factor independently associated with late AKI development (odds ratio = 4.4; 95% confidence interval = 1.3-15.4). Conclusions: Late AKI occurred in nearly 13% of children receiving ≥8 days of vancomycin therapy. This study suggests that vancomycin trough concentrations are not associated with late AKI, but that age <1 year and concomitant administration of certain nephrotoxins may be factors associated with increased risk.

Cinacalcet administration by gastrostomy tube in a child receiving peritoneal dialysis

A 2-year-old male with chronic kidney disease with secondary hyperparathyroidism developed hypercalcemia while receiving calcitriol, without achieving a serum parathyroid hormone concentration within the goal range. Cinacalcet 15 mg (1.2 mg/kg), crushed and administered via gastrostomy tube, was added to the patient's therapy. This therapy was effective in achieving targeted laboratory parameters in our patient despite instructions in the prescribing information that cinacalcet should always be taken whole.

Are Elevated Vancomycin Serum Trough Concentrations Achieved Within the First 7 Days of Therapy Associated With Acute Kidney Injury in Children?

BACKGROUND

In 2008, the empiric vancomycin dosing recommendation in children at our institution was changed from 40 to 60 mg/kg per day. Subsequently, an increased incidence of acute kidney injury (AKI) in patients receiving vancomycin was suspected. The objective of this study was to evaluate AKI in children receiving vancomycin and to determine risk factors for AKI development.

METHODS

Medical records of patients aged 30 days through 17 years who received vancomycin for at least 72 hours between January and December 2007 (40 mg/kg per day) and January and December 2010 (60 mg/kg per day) were reviewed. Patients with cystic fibrosis, an elevated baseline serum creatinine, or without a serum creatinine concentration obtained after receipt of vancomycin were excluded. Acute kidney injury was defined using adapted pediatric RIFLE criteria as an increase in serum creatinine from baseline of 50% or more.

RESULTS

Acute kidney injury occurred in 19.4% of the 859 children included, with no difference between the 2007 and 2010 periods (18.8% vs 20%, respectively; P = .636). Intensive care unit admission (odds ratio [OR], 1.86; 95% confidence interval [CI], 1.20-2.94) and an initial vancomycin trough concentration ≥15 mg/L (OR, 2.18; 95% CI, 1.21-3.92) were determined to be significantly associated with AKI.

CONCLUSIONS

These results suggest an initial vancomycin serum trough concentration of ≥15 mg/L and intensive care unit admission are predictors of AKI in this pediatric population.

100-fold reduction of electric-field noise in an ion trap cleaned with in situ argon-ion-beam bombardment

Motional heating of trapped atomic ions is a major obstacle to their use as quantum bits in a scalable quantum computer. The detailed physical origin of this heating is not well understood, but experimental evidence suggests that it is caused by electric-field noise emanating from the surface of the trap electrodes. In this study, we have investigated the role of adsorbates on the electrodes by identifying contaminant overlayers, implementing an in situ argon-ion-beam cleaning treatment, and measuring ion heating rates before and after treating the trap electrodes' surfaces. We find a 100-fold reduction in heating rate after treatment. The experiments described here are sensitive to low levels of electric-field noise in the MHz frequency range. Therefore, this approach could become a useful tool in surface science that complements established techniques.

Prevalence and correlates of multiple cardiovascular risk factors in children with chronic kidney disease

BACKGROUND AND OBJECTIVES

Although prevalence of traditional cardiovascular risk factors (CVRF) has been described in children with CKD, the frequency with which these CVRF occur concomitantly and the clinical characteristics associated with multiple CVRF are unknown. This study determined the prevalence and characteristics of multiple CVRF in children in the Chronic Kidney Disease in Children study.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Using cross-sectional data from first follow-up visits, we determined the prevalence of four CVRF: hypertension (casual BP >95(th) percentile or self-reported hypertension with concurrent use of anti-hypertensive medication), dyslipidemia (triglycerides >130 mg/dl, HDL <40 mg/dl, non-HDL >160 mg/dl, or use of lipid-lowering medication), obesity (BMI >95(th) percentile), and abnormal glucose metabolism (fasting glucose >110 mg/dl, insulin >20 μIU/ml, or HOMA-IR >2.20, >3.61, or >3.64 for those at Tanner stage 1, 2 to 3, or 4 to 5, respectively) in 250 children (median age 12.2 years, 74% Caucasian, median iohexol-based GFR 45.2 ml/min per 1.73 m(2)).

RESULTS

Forty-six percent had hypertension, 44% had dyslipidemia, 15% were obese, and 21% had abnormal glucose metabolism. Thirty-nine percent, 22%, and 13% had one, two, and three or more CVRF, respectively. In multivariate ordinal logistic regression analysis, glomerular disease and nephrotic-range proteinuria were associated with 1.96 (95% confidence interval, 1.04 to 3.72) and 2.04 (95% confidence interval, 0.94 to 4.43) higher odds of having more CVRF, respectively.

CONCLUSIONS

We found high prevalence of multiple CVRF in children with mild to moderate CKD. Children with glomerular disease may be at higher risk for future cardiovascular events.

Familial neuroendocrine cell hyperplasia of infancy

BACKGROUND

Neuroendocrine cell hyperplasia of infancy (NEHI) is a recently described children's interstitial lung disease (chILD) disorder of unknown etiology. It manifests clinically with tachypnea, retractions, hypoxemia, and crackles. The characteristic radiographic appearance consists of pulmonary hyperexpansion and ground-glass densities on high-resolution computed tomography (HRCT). Lung histology shows hyperplasia of bombesin-immunopositive neuroendocrine cells within distal bronchioles and alveolar ducts without other identifiable lung pathology or developmental anomaly.

METHODS

We describe four families with multiple siblings diagnosed with NEHI. Cases were identified at three pediatric centers. Inclusion criteria included clinical findings consistent with NEHI, lung biopsy confirmation in the index case, and a diagnostic HRCT or biopsy in other siblings.

RESULTS

Each family had a proband diagnosed with NEHI based upon pathologic review, and at least one additional sibling diagnosed either by pathologic review or HRCT. All patients presented between 2 and 15 months of age. Both male and female children were affected. The majority of the patients underwent both HRCT and lung biopsy. There were no deaths among affected children. No environmental exposures or other potential etiologies were identified as a cause of presenting symptoms.

CONCLUSIONS

The familial occurrence of NEHI suggests the possibility of a genetic etiology for this disorder and highlights the importance of taking a complete family medical history for infants presenting with a suggestive clinical picture. Identification of familial NEHI patients allows for the opportunity to further our understanding of this disorder, its natural history, the phenotypic spectrum, and potential genetic causes.

Rates of evolution in seed plants: Net increase in diversity of chromosome numbers and species numbers through time

An approach was made to the problem of estimating rates of chromosomal evolution in plants. This was done by considering variability in chromosome number within genera whose ages are known approximately from fossil and biogeographic evidence. The relative increases in chromosome number diversity per lineage per unit time were as follows: herbaceous angiosperms, 100; woody angiosperms, 14; conifers, 2; and cycads, 0. Rates of increase in species diversity were estimated in an analogous way. These rates were strongly correlated with the karyotypic rates.These evolutionary rate differences between major groups of seed plants are largely explicable in terms of the breeding structures of populations. Herbs usually have small to moderate effective population sizes, and relatively high dispersability. By contrast, woody angiosperms and gymnosperms are usually obligate outbreeders with large effective population sizes and low dispersability. Thus the probability of fixing and dispersing new karyotypes or novel character ensembles is higher in herbs than in other seed plants.

High prevalence of the metabolic syndrome and associated left ventricular hypertrophy in pediatric renal transplant recipients

The goal of this study was to estimate prevalence of the metabolic syndrome and its association with cardiac abnormalities in children with kidney transplant. A multi-center retrospective review of demographic, clinical, laboratory, and echocardiographic parameters at time of and at one-yr post-transplant was conducted in 234 pediatric recipients between 2000 and 2006. Eighty-eight patients (37.6%) met criteria for metabolic syndrome. Among 55 overweight patients, 40% had metabolic syndrome. Among 51 obese patients, 74.5% had metabolic syndrome. A total of 181 (71.0%) patients had complete data at both time points: prevalence of metabolic syndrome at time of transplant was 18.8%, compared with 37.0% at one-yr post-transplant (p < 0.0001). Among 147 patients without metabolic syndrome at time of transplant, 41 (27.9%) had developed metabolic syndrome by one-yr post-transplant. A total of patients from four centers had routine echocardiogram at one-yr post-transplant. LVH was significantly more common in those with metabolic syndrome (55%) than in those without (32%) (OR 2.6, 95% CI 1.2-5.9).

IN CONCLUSION

metabolic syndrome is common at time of pediatric kidney transplant, and prevalence rises sharply at one-yr post-transplant. The presence of metabolic syndrome is strongly associated with LVH in these patients.

Home oxygen for children with acute bronchiolitis

A prospective randomised controlled pilot study was performed comparing home oxygen therapy with traditional inpatient hospitalisation for children with acute bronchiolitis. Children aged 3-24 months with acute bronchiolitis, still requiring oxygen supplementation 24 h after admission to hospital, were randomly assigned to receive oxygen supplementation at home with support from "hospital in the home" (HiTH) or to continue oxygen supplementation in hospital. 44 children (26 male, mean age 9.2 months) were recruited (HiTH n = 22) between 1 August and 30 November 2007. Only one child from each group was readmitted to hospital and there were no serious complications. Children in the HiTH group spent almost 2 days less in a hospital bed than those managed as traditional inpatients: HiTH 55.2 h (interquartile range (IQR) 40.3-88.9) versus in hospital 96.9 h (IQR 71.2-147.2) p = 0.001. Home oxygen therapy appears to be a feasible alternative to traditional hospital oxygen therapy in selected children with acute bronchiolitis.

Cardiovascular disease in CKD in children: update on risk factors, risk assessment, and management

In young adults with onset of chronic kidney disease in childhood, cardiovascular disease is the most common cause of death. The likely reason for increased cardiovascular disease in these patients is a high prevalence of traditional and uremia-related cardiovascular disease risk factors during childhood chronic kidney disease. Early markers of cardiomyopathy, such as left ventricular hypertrophy and left ventricular dysfunction, and early markers of atherosclerosis, such as increased carotid artery intima-media thickness, carotid arterial wall stiffness, and coronary artery calcification, frequently are found in this patient population. The purpose of this review is to provide an update of recent advances in the understanding and management of cardiovascular disease risks in this population.

Systematically missing confounders in individual participant data meta-analysis of observational cohort studies

One difficulty in performing meta-analyses of observational cohort studies is that the availability of confounders may vary between cohorts, so that some cohorts provide fully adjusted analyses while others only provide partially adjusted analyses. Commonly, analyses of the association between an exposure and disease either are restricted to cohorts with full confounder information, or use all cohorts but do not fully adjust for confounding. We propose using a bivariate random-effects meta-analysis model to use information from all available cohorts while still adjusting for all the potential confounders. Our method uses both the fully adjusted and the partially adjusted estimated effects in the cohorts with full confounder information, together with an estimate of their within-cohort correlation. The method is applied to estimate the association between fibrinogen level and coronary heart disease incidence using data from 154 012 participants in 31 cohorts.† Copyright © 2009 John Wiley & Sons, Ltd.

Evolutionary genetics of ruminant lysozymes

Comparative studies of mammalian lysozymes and their genes have contributed to knowledge of how new functions arise during evolution. The recruitment of lysozymes for functioning in the stomach fluid of ruminants has occurred in response to selection pressures that are partly known and on a time-scale that is known. A semiquantitative analysis of adaptive evolution is thus made possible by the ruminant lysozyme system. Large-scale production of lysozyme by the stomach lining entailed gene duplication as well as a change in gene expression. Remoulding of the lysozyme for working and lasting in the stomach fluid involved accelerated amino acid replacements, which may have been facilitated by intergenic recombination. The possibility that multigene families can accelerate adaptive evolution, by virtue of their capacity for bringing together functionally coupled substitutions, receives emphasis in this review.

Current kidney allocation rules and their impact on a pediatric transplant center

In 2005, kidney allocation rules in the United States were updated to enhance access to kidneys from young adult deceased donors (DDs) for pediatric recipients. We studied how this rule change affected transplant activity at our pediatric center. We retrospectively compared kidney transplant activity at our center since the rule change (until December 31, 2007) to before the change (n = 36 each), focusing on those recipients directly affected by it, that is, younger than 18 years. There were no significant differences in recipients' age, gender or ethnicity before versus after the rule change. Percentages of preemptive transplants and retransplants were similar in both groups, as was the percentage of sensitized patients. There was a significant decrease in overall, but not DD, mean donor age. Mean wait time for DD kidneys decreased for pediatric recipients. Increases were found in percentage of DD transplants and in mean HLA mismatches after the rule change. Patient and short-term graft survival were not significantly different. These data suggest that the allocation rule change was not only followed by improvement in overall access to kidney transplantation for children, but also by decreases in living donor transplants and HLA matching. Larger studies are needed to evaluate the long-term impact of the change.

Flow-mediated vasodilatation of the brachial artery in children with chronic kidney disease

We sought to determine flow-mediated vasodilatation (FMD) of the brachial artery and to assess the relationship of FMD with multiple demographic, clinical and biochemical parameters and cardiac and vascular structure and function in children with chronic kidney disease (CKD) stages 2-4. Forty-three patients, aged 6-20 years, with CKD [mean glomerular filtration rate (GFR) 47 +/- 21 ml/min per 1.73 m2 body surface area, range 16-89 ml/min per 1.73 m2] and 34 healthy age-matched controls were included and studied cross-sectionally between 2001 and 2005. The peak FMD was similar in the CKD and control subjects (mean 6.3% vs 6.7%, P = 0.85). However, abnormally low FMD (< 1.1%) was found in ten (23%) children with CKD. Among children with CKD, those with low FMD were younger, shorter, lighter, and had lower body mass index (BMI) than children with normal FMD, but the difference reached statistical significance only for weight and BMI. Serum triglyceride levels were significantly lower in those with low FMD; otherwise, the two groups were similar with respect to multiple clinical and biochemical parameters. Cardiac and vascular structure was similar in children with normal and low FMD. In conclusion, children with CKD stage 2-4 appear to have increased prevalence of decreased FMD of the brachial artery. However, our study identified few significant factors associated with low FMD in children with CKD.

Early and late results of combined mitral-aortic valve surgery

OBJECTIVE

This retrospective study was designed to assess the early morbidity and mortality as well as long-term mortality of combined aortic-mitral valve procedures at a single centre.

METHODS

Patients were identified by analysing the intensive care and perfusion databases, from 1989 to 2003, with 113 receiving aortic-mitral valve procedures. Eighty-four percent of patients received a mechanical bileaflet valve. Survival was assessed using a Kaplan-Meier method, and determinants of survival with the Cox proportional hazards model.

RESULTS

There were 57 men and 56 women, median age 59 (18-84) years. The 30-day mortality was 9% (n=10). This cohort contained a number of high risk patients, 38% were classified as New York Heart Association class IV, 33.5% had at least moderate ventricular impairment, 20% were redo procedures and 17% urgent procedures. Survival estimates at 5 and 10 years were 85% (0.76-0.90) and 65% (0.49-0.77), respectively. Multivariate pre-operative predictors of death included renal dysfunction (creatinine >200 micromol/L) and hypertension. Rheumatic aetiology was associated with improved survival.

CONCLUSION

This study shows acceptable short and long-term survival in patients undergoing combined aortic-mitral valve surgical procedures at a single centre. Renal impairment and hypertension were associated with a poorer long-term prognosis and rheumatic aetiology was associated with improved survival. Age, LVEF and NYHA class were not associated with a worse outcome. This may affect future decision making in light of an aging population.

Widespread vascular production of C-reactive protein (CRP) and a relationship between serum CRP, plaque CRP and intimal hypertrophy

OBJECTIVES

Evidence of local vascular production and a relationship between serum hsCRP levels and tissue expression of CRP in subjects with vascular disease would support a direct role for CRP in atherosclerosis.

METHODS AND RESULTS

Vascular tissue from subjects undergoing coronary artery bypass grafting surgery (CABGS) (n=28) and carotid endarterectomy (CEA) (n=25) were studied. Histological samples were assessed for intima-media ratio (IMR) and CRP by immunohistochemistry. CRP mRNA was quantified by real-time polymerase chain reaction. CRP mRNA was seen in all plaques, non-atherosclerotic artery and atrium but no difference in mRNA expression was seen between plaque and non-atherosclerotic tissue. Serum hsCRP correlated with IMR (r=0.64, p=0.001) in non-atherosclerotic arteries and with plaque CRP staining (r=0.57, p=0.009) independent of age, BMI, lipids, diabetes and blood pressure. In a separate patient series, serum hsCRP was measured in aortic and coronary sinus blood from subjects undergoing CABGS or angiography (n=54). There was a coronary circulation hsCRP gradient ([mean+/-S.E.M.] aortic CRP 4.3mg/l+/-0.8 versus coronary sinus 5.8+/-1.2mg/l, p<0.05).

CONCLUSIONS

Widespread vascular CRP mRNA expression, a correlation between serum hsCRP, intimal hypertrophy and plaque CRP, and a coronary hsCRP gradient suggest vascular secretion may contribute to serum CRP levels.

Plasma fibrinogen level and the risk of major cardiovascular diseases and nonvascular mortality: an individual participant meta-analysis

CONTEXT

Plasma fibrinogen levels may be associated with the risk of coronary heart disease (CHD) and stroke.

OBJECTIVE

To assess the relationships of fibrinogen levels with risk of major vascular and with risk of nonvascular outcomes based on individual participant data.

DATA SOURCES

Relevant studies were identified by computer-assisted searches, hand searches of reference lists, and personal communication with relevant investigators.

STUDY SELECTION

All identified prospective studies were included with information available on baseline fibrinogen levels and details of subsequent major vascular morbidity and/or cause-specific mortality during at least 1 year of follow-up. Studies were excluded if they recruited participants on the basis of having had a previous history of cardiovascular disease; participants with known preexisting CHD or stroke were excluded.

DATA EXTRACTION

Individual records were provided on each of 154,211 participants in 31 prospective studies. During 1.38 million person-years of follow-up, there were 6944 first nonfatal myocardial infarctions or stroke events and 13,210 deaths. Cause-specific mortality was generally available. Analyses involved proportional hazards modeling with adjustment for confounding by known cardiovascular risk factors and for regression dilution bias.

DATA SYNTHESIS

Within each age group considered (40-59, 60-69, and > or =70 years), there was an approximately log-linear association with usual fibrinogen level for the risk of any CHD, any stroke, other vascular (eg, non-CHD, nonstroke) mortality, and nonvascular mortality. There was no evidence of a threshold within the range of usual fibrinogen level studied at any age. The age- and sex- adjusted hazard ratio per 1-g/L increase in usual fibrinogen level for CHD was 2.42 (95% confidence interval [CI], 2.24-2.60); stroke, 2.06 (95% CI, 1.83-2.33); other vascular mortality, 2.76 (95% CI, 2.28-3.35); and nonvascular mortality, 2.03 (95% CI, 1.90-2.18). The hazard ratios for CHD and stroke were reduced to about 1.8 after further adjustment for measured values of several established vascular risk factors. In a subset of 7011 participants with available C-reactive protein values, the findings for CHD were essentially unchanged following additional adjustment for C-reactive protein. The associations of fibrinogen level with CHD or stroke did not differ substantially according to sex, smoking, blood pressure, blood lipid levels, or several features of study design.

CONCLUSIONS

In this large individual participant meta-analysis, moderately strong associations were found between usual plasma fibrinogen level and the risks of CHD, stroke, other vascular mortality, and nonvascular mortality in a wide range of circumstances in healthy middle-aged adults. Assessment of any causal relevance of elevated fibrinogen levels to disease requires additional research.

Production efficiency of ultracold feshbach molecules in bosonic and fermionic systems

We investigate the production efficiency of ultracold molecules in bosonic 85Rb and fermionic 40K when the magnetic field is swept across a Feshbach resonance. For adiabatic sweeps of the magnetic field, our novel model shows that the conversion efficiency of both species is solely determined by the phase space density of the atomic cloud, in contrast with a number of theoretical predictions. In the nonadiabatic regime our measurements of the 85Rb molecule conversion efficiency follow a Landau-Zener model.

Experimental investigation of early-time diffusion in the quantum kicked rotor using a Bose-Einstein condensate

We report measurements of the early-time momentum diffusion for the atom-optical delta-kicked rotor. In this experiment a Bose-Einstein condensate provides a source of ultracold atoms with an ultranarrow initial momentum distribution, which is then subjected to periodic pulses (or "kicks") using an intense far-detuned optical standing wave. We characterize the effect of varying the effective Planck's constant for the system, while keeping all other parameters fixed. The observed behavior includes both quantum resonances (ballistic energy growth) and antiresonances (re-establishment of the initial state). Our experimental results are compared with theoretical predictions.

A randomized control trial of the effect of negotiated telephone support on glycaemic control in young people with Type 1 diabetes

AIM

To evaluate changes in self-efficacy for self-management in young people with Type 1 diabetes participating in a "Negotiated Telephone Support" (NTS) intervention developed using the principles of problem solving and social learning theory.

METHODS

One-year RCT with 79 young people (male 39; mean age +/- sd 16.5 +/- 3.2 years, duration 6.7 +/- 4.4 years, HbA(1c) 8.6 +/- 1.5%) randomized into: Group 1 (control group), continued routine management, n = 28; Group 2, continued routine management with NTS, n = 25; Group 3, annual clinic with NTS, n = 26.

OUTCOME MEASURES

HbA(1c), self-efficacy, barriers to adherence, problem solving, and diabetes knowledge.

RESULTS

There were no differences between the groups at baseline. Participants in Groups 2 and 3 received an average of 16 telephone calls/year (range 5-19), median duration 9 min (2-30), with a median interval of 3 weeks (1-24) between calls. Significant correlations were found between age and average length of call (r = 0.44, P < 0.01) and frequency of contact (r = 0.36, P < 0.05). Social and school topics were discussed frequently. After 1 year, while the participants in the two intervention groups showed significant improvements in self-efficacy (P = 0.035), there was no difference in glycaemic control in the three groups. Barriers to insulin use adherence were a significant predictor of HbA(1c) (P < 0.001) after controlling for baseline.

CONCLUSIONS

NTS is an effective medium to deliver a simple theory-based psychological intervention to enhance self-efficacy for diabetes self-management. Reduced clinic attendance, combined with NTS, did not result in a deterioration of HbA(1c). Intensive personal support needs to be combined with intensive diabetes therapy to improve glycaemic control in this age group.

Time trends in the occurrence and outcome of acute myocardial infarction and coronary heart disease death between 1986 and 1996 (a New Jersey statewide study)

Most reports of the decrease in age-adjusted coronary heart disease (CHD) are based on databases with upper age cut-offs that exclude approximately half of the events. We report changes in rates of acute myocardial infarction (AMI) and of out-of-hospital coronary death between 1986 and 1996 among New Jersey residents > or =15 years old. Data on patients discharged with the diagnosis of AMI from nonfederal acute care hospitals in the state (n = 270,091) and all records in the New Jersey death registration files with CHD (n = 172,175) listed as the cause of death from 1986 to 1996 (total study n = 442,266) were analyzed. The rate of hospitalized AMI cases in the state remained essentially unchanged during these 11 years, whereas in-hospital and 30-day case fatality among all age groups and both sexes declined. Age-adjusted CHD rates showed a decrease in fatal events, a smaller decrease in total events, and a slight increase in nonfatal events. The proportion of fatal CHD events occurring out-of-hospital decreased especially among men. The median age at occurrence of events increased by 1 year. Despite a decrease in CHD mortality, the rate of nonfatal events increased, especially among persons > or =75 years old. Thus, the decrease in age-adjusted CHD mortality is not all due to treatment and true prevention of CHD, but the disease simply occurs at an older age.

Association of increased pulse pressure with the development of heart failure in SHEP. Systolic Hypertension in the Elderly (SHEP) Cooperative Research Group

The aim of this study was to assess the relationship between pulse pressure (PP) and the occurrence of heart failure (HF) in older persons with isolated systolic hypertension. Data from a prospective, multicenter, randomized, double-blind, placebo-controlled clinical trial were analyzed. A total of 4736 persons aged > or = 60 years with systolic blood pressure (SBP) between 160 and 219 mm Hg and diastolic blood pressure (DBP) < 90 mm Hg who participated in the Systolic Hypertension in the Elderly Program (SHEP) were studied. The main outcome measures were fatal and nonfatal HF. During 4.5 years average follow-up, fatal or nonfatal HF occurred in 160 of 4736 patients. The SBP, PP, and mean arterial pressure (MAP) were strong predictors of the development of HF (P < .0002). Cox proportional hazards regression using time-dependent covariates and controlling for MAP indicated that HF was inversely related to DBP (P = 0.002) and was directly related to pulse pressure (P = 0.002). Data were similar when patients who developed myocardial infarction during follow up were excluded. These data indicate that, in older persons with isolated systolic hypertension, high pulse pressure is associated with increased risk of heart failure independently of MAP and of the occurrence of acute myocardial infarction during follow-up.

Microsatellite isolation, linkage group identification and determination of recombination frequency in the peach-potato aphid, Myzus persicae (Sulzer) (Hemiptera: Aphididae)

Fifteen polymorphic microsatellite markers were used to establish linkage groups and relative rates of recombination in male and female Myzus persicae (Sulzer) (Hemiptera: Aphididae) (peach-potato aphid). We cloned nine markers from M. persicae and for these we report primer sequences and levels of allelic diversity and heterozygosity in four Australian M. persicae populations. Of the remaining six loci, four loci, also cloned from M. persicae, were obtained from G. Malarky (Natural History Museum, London) and two loci from Sitobion miscanthi were used. Additionally, the primer sequences of locus M77, a locus monomorphic in M. persicae but polymorphic in the closely related Myzus antirrhinii, are presented. Eleven of the 15 polymorphic markers were autosomal and four were X-linked. A linkage analysis was performed on a European pedigree of aphids containing five families with between seven and 11 offspring each. There was no linkage between any loci in females. In males, several pairwise comparisons yielded no recombinant offspring. With the exception of locus M40, these observations were supported in a linkage analysis performed on larger families produced from Australian M. persicae crosses. Locus M40 showed segregation consistent with involvement in a translocation between autosomes 1 and 3 in European samples but not in the Australian samples. From the Australian crosses we report an absence of recombination in males but high recombination rates in females. One X chromosome and four autosomal linkage groups were identified and tentatively assigned to chromosomes. The relevance of achiasmate meiosis to the evolution of sex is discussed.

Statistical issues in analyzing 24-hour dietary recall and 24-hour urine collection data for sodium and potassium intakes

Dietary recalls and urine assays provide different metrics for assessing sodium and potassium intakes. Means, variances, and correlations of data obtained from these two modes of measurement differ. Pooling of these data is not straightforward, and results from studies employing the different modes may not be comparable. To explore differences between these metrics, the authors used data from the Trial of Nonpharmacologic Intervention in the Elderly (TONE), which included repeated standardized 24-hour dietary recalls and 24-hour urine collections administered over 3 years of follow-up, to estimate sodium and potassium intakes. The authors examined data from 341 control participants assigned to usual care that were collected between August 1992 and December 1995. Dietary recalls yielded estimates of sodium intake that averaged 22% less than those from urine assays and estimates of potassium intake that averaged 16% greater than those from urine assays. Sodium intake estimates were less repeatable (r = 0.22 for diet; r = 0.30 for urine) than potassium intake estimates (r = 0.49 for diet; r = 0.50 for urine), making relations with outcomes more difficult to characterize. Overall, the performance of the two measurement modes was fairly similar across demographic subgroups. Errors in separate estimations of long term sodium and potassium intakes using short term data were strongly correlated, more strongly than the underlying long term intakes of these electrolytes. Because of the correlated measurement error, estimated regression coefficients for linear models including both electrolytes as predictors may be confounded such that the separate relations between these nutrients and outcomes such as blood pressure cannot be reliably estimated by common analytical strategies.