Hypertension and Kidney Function After Living Kidney Donation.

Importance: Recent guidelines call for better evidence on health outcomes after living kidney donation. Objective: To determine the risk of hypertension in normotensive adults who donated a kidney compared with nondonors of similar baseline health. Their rates of estimated glomerular filtration rate (eGFR) decline and risk of albuminuria were also compared. Design, Setting, and Participants: Prospective cohort study of 924 standard-criteria living kidney donors enrolled before surgery and a concurrent sample of 396 nondonors. Recruitment occurred from 2004 to 2014 from 17 transplant centers (12 in Canada and 5 in Australia); follow-up occurred until November 2021. Donors and nondonors had the same annual schedule of follow-up assessments. Inverse probability of treatment weighting on a propensity score was used to balance donors and nondonors on baseline characteristics. Exposure: Living kidney donation. Main Outcomes and Measures: Hypertension (systolic blood pressure [SBP] ≥140 mm Hg, diastolic blood pressure [DBP] ≥90 mm Hg, or antihypertensive medication), annualized change in eGFR (starting 12 months after donation/simulated donation date in nondonors), and albuminuria (albumin to creatinine ratio ≥3 mg/mmol [≥30 mg/g]). Results: Among the 924 donors, 66% were female; they had a mean age of 47 years and a mean eGFR of 100 mL/min/1.73 m2. Donors were more likely than nondonors to have a family history of kidney failure (464/922 [50%] vs 89/394 [23%], respectively). After statistical weighting, the sample of nondonors increased to 928 and baseline characteristics were similar between the 2 groups. During a median follow-up of 7.3 years (IQR, 6.0-9.0), in weighted analysis, hypertension occurred in 161 of 924 donors (17%) and 158 of 928 nondonors (17%) (weighted hazard ratio, 1.11 [95% CI, 0.75-1.66]). The longitudinal change in mean blood pressure was similar in donors and nondonors. After the initial drop in donors' eGFR after nephrectomy (mean, 32 mL/min/1.73 m2), donors had a 1.4-mL/min/1.73 m2 (95% CI, 1.2-1.5) per year lesser decline in eGFR than nondonors. However, more donors than nondonors had an eGFR between 30 and 60 mL/min/1.73 m2 at least once in follow-up (438/924 [47%] vs 49/928 [5%]). Albuminuria occurred in 132 of 905 donors (15%) and 95 of 904 nondonors (11%) (weighted hazard ratio, 1.46 [95% CI, 0.97-2.21]); the weighted between-group difference in the albumin to creatinine ratio was 1.02 (95% CI, 0.88-1.19). Conclusions and Relevance: In this cohort study of living kidney donors and nondonors with the same follow-up schedule, the risks of hypertension and albuminuria were not significantly different. After the initial drop in eGFR from nephrectomy, donors had a slower mean rate of eGFR decline than nondonors but were more likely to have an eGFR between 30 and 60 mL/min/1.73 m2 at least once in follow-up. Trial Registration: ClinicalTrials.gov Identifier: NCT00936078.

The effect of micro-particle curcumin on chronic kidney disease progression: the MPAC-CKD randomized clinical trial.

BACKGROUND: Curcumin is a commonly used herbal supplement with anti-inflammatory and anti-fibrotic properties. Animal studies and small human trials suggest that curcumin reduces albuminuria in patients with chronic kidney disease (CKD). Micro-particle curcumin is a new, more bioavailable formulation of curcumin. METHODS: To determine whether micro-particle curcumin versus placebo slows the progression of albuminuric CKD we conducted a randomized, double-blind, placebo-controlled trial with 6-month follow-up. We included adults with albuminuria [a random urine albumin-to-creatinine ratio >30 mg/mmol (265 mg/g) or a 24-h urine collection with more than 300 mg of protein] and an estimated glomerular filtration rate (eGFR) between 15 and 60 mL/min/1.73 m2 within the 3 months before randomization. We randomly allocated participants 1:1 to receive micro-particle curcumin capsules (90 mg/day) or matching placebo for 6 months. After randomization, the co-primary outcomes were the changes in albuminuria and the eGFR. RESULTS: We enrolled 533 participants, but 4/265 participants in the curcumin group and 15/268 in the placebo group withdrew consent or became ineligible. The 6-month change in albuminuria did not differ significantly between the curcumin and placebo groups [geometric mean ratio 0.94, 97.5% confidence interval (CI) 0.82 to 1.08, P = .32]. Similarly, the 6-month change in eGFR did not differ between groups (mean between-group difference -0.22 mL/min/1.73 m2, 97.5% CI -1.38 to 0.95, P = .68). CONCLUSIONS: Ninety milligrams of micro-particle curcumin daily did not slow the progression of albuminuric CKD over 6 months. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02369549.

Impact of Perioperative Complications on Living Kidney Donor Health-Related Quality of Life and Mental Health: Results From a Prospective Cohort Study.

BACKGROUND: Although living kidney donation is safe, some donors experience perioperative complications. OBJECTIVE: This study explored how perioperative complications affected donor-reported health-related quality of life, depression, and anxiety. DESIGN: This research was a conducted as a prospective cohort study. SETTING: Twelve transplant centers across Canada. PATIENTS: A total of 912 living kidney donors were included in this study. MEASUREMENTS: Short Form 36 health survey, Beck Depression Inventory and Beck Anxiety Inventory. METHODS: Living kidney donors were prospectively enrolled predonation between 2009 to 2014. Donor perioperative complications were graded using the Clavien-Dindo classification system. Mental and physical health-related quality of life was assessed with the 3 measurements; measurements were taken predonation and at 3- and 12-months postdonation. RESULTS: Seventy-four donors (8%) experienced a perioperative complication; most were minor (n = 67 [91%]), and all minor complications resolved before hospital discharge. The presence (versus absence) of a perioperative complication was associated with lower mental health-related quality of life and higher depression symptoms 3-month postdonation; neither of these differences persisted at 12-month. Perioperative complications were not associated with any changes in physical health-related quality of life or anxiety 3-month postdonation. LIMITATIONS: Minor complications may have been missed and information on complications postdischarge were not collected. No minimal clinically significant change has been defined for kidney donors across the 3 measurements. CONCLUSIONS: These findings highlight a potential opportunity to better support the psychosocial needs of donors who experience perioperative complications in the months following donation. TRIAL REGISTRATION: NCT00319579 and NCT00936078.

CONTEXTE: Bien que le don vivant d'un rein soit une procédure sécuritaire, certains donneurs souffrent tout de même de complications périopératoires. OBJECTIFS: Cette étude a examiné l'incidence des complications périopératoires sur la qualité de vie liée à la santé et les symptômes de dépression et d'anxiété rapportés par les donneurs. TYPE D'ÉTUDE: Étude de cohorte prospective. CADRE: Douze centers de transplantation à travers le Canada. SUJETS: 912 donneurs vivants d'un rein. MESURES: Un questionnaire abrégé de 36 questions sur l'état de santé, l'inventaire de dépression Beck et l'inventaire d'anxiété Beck. MÉTHODOLOGIE: Les donneurs ont été inscrits avant le don de façon prospective entre 2009 et 2014. Les complications périopératoires des donneurs ont été classées à l'aide du système de classification Clavien-Dindo. La qualité de vie liée à la santé physique et mentale a été évaluée à l'aide des trois outils de mesure; ces mesures ont été faites avant le don, puis 3 et 12 mois après le don. RÉSULTATS: Au total, 74 donneurs (8 %) ont souffert d'une complication périopératoire; la plupart étaient mineures (n = 67 [91 %]) et ont été résolues avant le congé de l'hôpital. La présence (par rapport à l'absence) d'une complication périopératoire a été associée à une plus faible qualité de vie liée à la santé mentale et à des symptômes de dépression plus graves 3 mois après le don; aucune de ces différences n'a persisté après 12 mois. Les complications périopératoires n'ont pas été associées à des changements dans la qualité de vie liée à la santé physique ou à l'anxiété 3 mois après le don. LIMITES: Certaines complications mineures ont pu être manquées. L'information sur les complications survenues après le congé n'a pas été recueillie. Dans les trois outils de mesure, aucune variation minimale cliniquement significative n'a été définie pour les donneurs d'un rein. CONCLUSION: Ces résultats soulignent une occasion de mieux répondre aux besoins psychosociaux des donneurs d'un rein qui présentent des complications périopératoires dans les mois suivant le don.

Three Statistical Approaches for Assessment of Intervention Effects: A Primer for Practitioners.

INTRODUCTION: Statistical methods to assess the impact of an intervention are increasingly used in clinical research settings. However, a comprehensive review of the methods geared toward practitioners is not yet available. METHODS AND MATERIALS: We provide a comprehensive review of three methods to assess the impact of an intervention: difference-in-differences (DID), segmented regression of interrupted time series (ITS), and interventional autoregressive integrated moving average (ARIMA). We also compare the methods, and provide illustration of their use through three important healthcare-related applications. RESULTS: In the first example, the DID estimate of the difference in health insurance coverage rates between expanded states and unexpanded states in the post-Medicaid expansion period compared to the pre-expansion period was 5.93 (95% CI, 3.99 to 7.89) percentage points. In the second example, a comparative segmented regression of ITS analysis showed that the mean imaging order appropriateness score in the emergency department at a tertiary care hospital exceeded that of the inpatient setting with a level change difference of 0.63 (95% CI, 0.53 to 0.73) and a trend change difference of 0.02 (95% CI, 0.01 to 0.03) after the introduction of a clinical decision support tool. In the third example, the results from an interventional ARIMA analysis show that numbers of creatinine clearance tests decreased significantly within months of the start of eGFR reporting, with a magnitude of drop equal to -0.93 (95% CI, -1.22 to -0.64) tests per 100,000 adults and a rate of drop equal to 0.97 (95% CI, 0.95 to 0.99) tests per 100,000 per adults per month. DISCUSSION: When choosing the appropriate method to model the intervention effect, it is necessary to consider the structure of the data, the study design, availability of an appropriate comparison group, sample size requirements, whether other interventions occur during the study window, and patterns in the data.

Living Kidney Donors' Financial Expenses and Mental Health.

BACKGROUND: Living kidney donors incur donation-related expenses, but how these expenses impact postdonation mental health is unknown. METHODS: In this prospective cohort study, the association between mental health and donor-incurred expenses (both out-of-pocket costs and lost wages) was examined in 821 people who donated a kidney at one of the 12 transplant centers in Canada between 2009 and 2014. Mental health was measured by the RAND Short Form-36 Health Survey along with Beck Anxiety Inventory and Beck Depression Inventory. RESULTS: A total of 209 donors (25%) reported expenses of >5500 Canadian dollars. Compared with donors who incurred lower expenses, those who incurred higher expenses demonstrated significantly worse mental health-related quality of life 3 months after donation, with a trend towards worse anxiety and depression, after controlling for predonation mental health-related quality of life and other risk factors for psychological distress. Between-group differences for donors with lower and higher expenses on these measures were no longer significant 12 months after donation. CONCLUSIONS: Living kidney donor transplant programs should ensure that adequate psychosocial support is available to all donors who need it, based on known and unknown risk factors. Efforts to minimize donor-incurred expenses and to better support the mental well-being of donors need to continue. Further research is needed to investigate the effect of donor reimbursement programs, which mitigate donor expenses, on postdonation mental health.

Safety of a Restrictive versus Liberal Approach to Red Blood Cell Transfusion on the Outcome of AKI in Patients Undergoing Cardiac Surgery: A Randomized Clinical Trial.

BACKGROUND: Safely reducing red blood cell transfusions can prevent transfusion-related adverse effects, conserve the blood supply, and reduce health care costs. Both anemia and red blood cell transfusion are independently associated with AKI, but observational data are insufficient to determine whether a restrictive approach to transfusion can be used without increasing AKI risk. METHODS: In a prespecified kidney substudy of a randomized noninferiority trial, we compared a restrictive threshold for red blood cell transfusion (transfuse if hemoglobin<7.5 g/dl, intraoperatively and postoperatively) with a liberal threshold (transfuse if hemoglobin<9.5 g/dl in the operating room or intensive care unit, or if hemoglobin<8.5 g/dl on the nonintensive care ward). We studied 4531 patients undergoing cardiac surgery with cardiopulmonary bypass who had a moderate-to-high risk of perioperative death. The substudy's primary outcome was AKI, defined as a postoperative increase in serum creatinine of ≥0.3 mg/dl within 48 hours of surgery, or ≥50% within 7 days of surgery. RESULTS: Patients in the restrictive-threshold group received significantly fewer transfusions than patients in the liberal-threshold group (1.8 versus 2.9 on average, or 38% fewer transfusions in the restricted-threshold group compared with the liberal-threshold group; P<0.001). AKI occurred in 27.7% of patients in the restrictive-threshold group (624 of 2251) and in 27.9% of patients in the liberal-threshold group (636 of 2280). Similarly, among patients with preoperative CKD, AKI occurred in 33.6% of patients in the restrictive-threshold group (258 of 767) and in 32.5% of patients in the liberal-threshold group (252 of 775). CONCLUSIONS: Among patients undergoing cardiac surgery, a restrictive transfusion approach resulted in fewer red blood cell transfusions without increasing the risk of AKI.

Effect of methylprednisolone on acute kidney injury in patients undergoing cardiac surgery with a cardiopulmonary bypass pump: a randomized controlled trial.

BACKGROUND: Perioperative corticosteroid use may reduce acute kidney injury. We sought to test whether methylprednisolone reduces the risk of acute kidney injury after cardiac surgery. METHODS: We conducted a prespecified substudy of a randomized controlled trial involving patients undergoing cardiac surgery with cardiopulmonary bypass (2007-2014); patients were recruited from 79 centres in 18 countries. Eligibility criteria included a moderate-to-high risk of perioperative death based on a preoperative score of 6 or greater on the European System for Cardiac Operative Risk Evaluation I. Patients (n = 7286) were randomly assigned (1:1) to receive intravenous methylprednisolone (250 mg at anesthetic induction and 250 mg at initiation of cardiopulmonary bypass) or placebo. Patients, caregivers, data collectors and outcome adjudicators were unaware of the assigned intervention. The primary outcome was postoperative acute kidney injury, defined as an increase in the serum creatinine concentration (from the preoperative value) of 0.3 mg/dL or greater (≥ 26.5 µmol/L) or 50% or greater in the 14-day period after surgery, or use of dialysis within 30 days after surgery. RESULTS: Acute kidney injury occurred in 1479/3647 patients (40.6%) in the methylprednisolone group and in 1426/3639 patients (39.2%) in the placebo group (adjusted relative risk 1.04, 95% confidence interval 0.96 to 1.11). Results were consistent across several definitions of acute kidney injury and in patients with preoperative chronic kidney disease. INTERPRETATION: Intraoperative corticosteroid use did not reduce the risk of acute kidney injury in patients with a moderate-to-high risk of perioperative death who had cardiac surgery with cardiopulmonary bypass. Our results do not support the prophylactic use of steroids during cardiopulmonary bypass surgery. Trial registration: ClinicalTrials.gov, no. NCT00427388.

Financial Costs Incurred by Living Kidney Donors: A Prospective Cohort Study.

BACKGROUND: Approximately 40% of the kidneys for transplant worldwide come from living donors. Despite advantages of living donor transplants, rates have stagnated in recent years. One possible barrier may be costs related to the transplant process that potential willing donors may incur for travel, parking, accommodation, and lost productivity. METHODS: To better understand and quantify the financial costs incurred by living kidney donors, we conducted a prospective cohort study, recruiting 912 living kidney donors from 12 transplant centers across Canada between 2009 and 2014; 821 of them completed all or a portion of the costing survey. We report microcosted total, out-of-pocket, and lost productivity costs (in 2016 Canadian dollars) for living kidney donors from donor evaluation start to 3 months after donation. We examined costs according to (1) the donor's relationship with their recipient, including spousal (donation to a partner), emotionally related nonspousal (friend, step-parent, in law), or genetically related; and (2) donation type (directed, paired kidney, or nondirected). RESULTS: Living kidney donors incurred a median (75th percentile) of $1254 ($2589) in out-of-pocket costs and $0 ($1908) in lost productivity costs. On average, total costs were $2226 higher in spousal compared with emotionally related nonspousal donors (P=0.02) and $1664 higher in directed donors compared with nondirected donors (P<0.001). Total costs (out-of-pocket and lost productivity) exceeded $5500 for 205 (25%) donors. CONCLUSIONS: Our results can be used to inform strategies to minimize the financial burden of living donation, which may help improve the donation experience and increase the number of living donor kidney transplants.

Effect of Coaching to Increase Water Intake on Kidney Function Decline in Adults With Chronic Kidney Disease: The CKD WIT Randomized Clinical Trial.

Importance: In observational studies, increased water intake is associated with better kidney function. Objective: To determine the effect of coaching to increase water intake on kidney function in adults with chronic kidney disease. Design, Setting, and Participants: The CKD WIT (Chronic Kidney Disease Water Intake Trial) randomized clinical trial was conducted in 9 centers in Ontario, Canada, from 2013 until 2017 (last day of follow-up, May 25, 2017). Patients had stage 3 chronic kidney disease (estimated glomerular filtration rate [eGFR] 30-60 mL/min/1.73 m2 and microalbuminuria or macroalbuminuria) and a 24-hour urine volume of less than 3.0 L. Interventions: Patients in the hydration group (n = 316) were coached to drink more water, and those in the control group (n = 315) were coached to maintain usual intake. Main Outcomes and Measures: The primary outcome was change in kidney function (eGFR from baseline to 12 months). Secondary outcomes included 1-year change in plasma copeptin concentration, creatinine clearance, 24-hour urine albumin, and patient-reported overall quality of health (0 [worst possible] to 10 [best possible]). Results: Of 631 randomized patients (mean age, 65.0 years; men, 63.4%; mean eGFR, 43 mL/min/1.73 m2; median urine albumin, 123 mg/d), 12 died (hydration group [n = 5]; control group [n = 7]). Among 590 survivors with 1-year follow-up measurements (95% of 619), the mean change in 24-hour urine volume was 0.6 L per day higher in the hydration group (95% CI, 0.5 to 0.7; P < .001). The mean change in eGFR was -2.2 mL/min/1.73 m2 in the hydration group and -1.9 mL/min/1.73 m2 in the control group (adjusted between-group difference, -0.3 mL/min/1.73 m2 [95% CI, -1.8 to 1.2; P = .74]). The mean between-group differences (hydration vs control) in secondary outcomes were as follows: plasma copeptin, -2.2 pmol/L (95% CI, -3.9 to -0.5; P = .01); creatinine clearance, 3.6 mL/min/1.73 m2 (95% CI, 0.8 to 6.4; P = .01); urine albumin, 7 mg per day (95% CI, -4 to 51; P = .11); and quality of health, 0.2 points (95% CI, -0.3 to 0.3; P = .22). Conclusions and Relevance: Among adults with chronic kidney disease, coaching to increase water intake compared with coaching to maintain the same water intake did not significantly slow the decline in kidney function after 1 year. However, the study may have been underpowered to detect a clinically important difference. Trial Registration: clinicaltrials.gov Identifier: NCT01766687.

Risk of Acute Kidney Injury in Patients Randomized to a Restrictive Versus Liberal Approach to Red Blood Cell Transfusion in Cardiac Surgery: A Substudy Protocol of the Transfusion Requirements in Cardiac Surgery III Noninferiority Trial.

BACKGROUND: When safe to do so, avoiding blood transfusions in cardiac surgery can avoid the risk of transfusion-related infections and other complications while protecting a scarce resource and reducing costs. This protocol describes a kidney substudy of the Transfusion Requirements in Cardiac Surgery III (TRICS-III) trial, a multinational noninferiority randomized controlled trial to determine whether the risk of major clinical outcomes in patients undergoing planned cardiac surgery with cardiopulmonary bypass is no greater with a restrictive versus liberal approach to red blood cell transfusion. OBJECTIVE: The objective of this substudy is to determine whether the risk of acute kidney injury is no greater with a restrictive versus liberal approach to red blood cell transfusion, and whether this holds true in patients with and without preexisting chronic kidney disease. DESIGN AND SETTING: Multinational noninferiority randomized controlled trial conducted in 73 centers in 19 countries (2014-2017). PATIENTS: Patients (~4800) undergoing planned cardiac surgery with cardiopulmonary bypass. MEASUREMENTS: The primary outcome of this substudy is perioperative acute kidney injury, defined as an acute rise in serum creatinine from the preoperative value (obtained in the 30-day period before surgery), where an acute rise is defined as ≥26.5 µmol/L in the first 48 hours after surgery or ≥50% in the first 7 days after surgery. METHODS: We will report the absolute risk difference in acute kidney injury and the 95% confidence interval. We will repeat the primary analysis using alternative definitions of acute kidney injury, including staging definitions, and will examine effect modification by preexisting chronic kidney disease (defined as a preoperative estimated glomerular filtration rate [eGFR] <60 mL/min/1.73 m2). LIMITATIONS: It is not possible to blind patients or providers to the intervention; however, objective measures will be used to assess outcomes, and outcome assessors will be blinded to the intervention assignment. RESULTS: Substudy results will be reported by the year 2018. CONCLUSIONS: This substudy will provide generalizable estimates of the risk of acute kidney injury of a restrictive versus liberal approach to red blood cell transfusion in the presence of anemia during cardiac surgery done with cardiopulmonary bypass. TRIAL REGISTRATION: www.clinicaltrials.gov; clinical trial registration number NCT 02042898.

CONTEXTE: En chirurgie cardiaque, éviter les transfusions sanguines, lorsque sécuritaire, contribue à réduire les risques d'infections transfusionnelles et de complications tout en préservant une ressource rare et en réduisant le coût des soins. Ce protocole décrit une étude secondaire qui examine le volet des risques d'insuffisance rénale aiguë (IRA) de l'étude TRICS-III (Transfusion Requirements in Cardiac Surgery III), un essai de non-infériorité multinational, contrôlé et à répartition aléatoire faisant état des exigences applicables à la transfusion sanguine en chirurgie cardiaque. Notre protocole vise plus particulièrement à déterminer si le risque d'atteintes rénales encouru par les patients subissant une chirurgie de pontages coronarien est plus ou moins grand selon que l'on préconise une approche restrictive ou libérale en matière de transfusion sanguine. OBJECTIF: L'objectif de notre étude est de déterminer si le risque d'IRA est plus ou moins grand selon que l'on préconise une approche restrictive ou libérale à l'égard de la transfusion sanguine; et, si c'est le cas, d'établir si ce risque différentiel perdure selon que le patient était ou non atteint d'insuffisance rénale chronique avant l'intervention. CADRE ET TYPE D'ÉTUDE: L'étude consiste en un essai multinational de non-infériorité, contrôlé et à répartition aléatoire, mené entre 2014 et 2017 au sein de 73 centres répartis dans 19 pays. PATIENTS: L'étude compte environ 4 800 patients ayant subi un pontage coronarien. MESURES: Le principal facteur observé est le développement d'une IRA périopératoire, telle que définie par une hausse marquée du taux de créatinine sérique par rapport à la valeur préopératoire (prélevée dans les 30 jours précédant l'intervention). Nous avons défini une « hausse marquée ¼ par un taux de créatinine atteignant au moins 26,5µmol/L dans les 48 heures postopératoires ou son augmentation d'au moins 50 % à l'intérieur des sept premiers jours. MÉTHODOLOGIE: Nous présenterons le risque différentiel absolu d'IRA dans un intervalle de confiance à 95 %. Nous répéterons l'analyse primaire en alternant les définitions de l'IRA (notamment en fonction des différents stades) et examinerons les éventuelles modifications de l'incidence chez des patients atteints d'une insuffisance rénale préexistante (définie par un DFGe préopératoire à moins de 60 ml/min/1,73 m2). LIMITES DE L'ÉTUDE: Il n'est évidemment pas possible de procéder à l'insu des patients ni des fournisseurs de soins lors de l'intervention. Toutefois, des mesures objectives seront utilisées pour évaluer les résultats, et les évaluateurs ne seront aucunement au courant de la répartition des cas. RÉSULTATS: Les résultats de cette étude secondaire seront présentés d'ici 2018. CONCLUSION: Cette étude secondaire fournira des estimations généralisables du risque de développer une IRA lors d'un pontage coronarien selon que, pour traiter l'anémie, l'approche à l'égard de la transfusion sanguine soit restrictive ou libérale.

Micro-Particle Curcumin for the Treatment of Chronic Kidney Disease-1: Study Protocol for a Multicenter Clinical Trial.

BACKGROUND: The progression to end-stage renal disease (ESRD) is the most important complication of chronic kidney disease (CKD). Patients with ESRD require dialysis or transplantation to survive, incur numerous complications, and have high mortality rates. Slowing the progression of CKD is an important goal. Unfortunately, even when current treatments are appropriately applied, patients with CKD still progress to ESRD. Current treatments do not address the inflammation and fibrosis that mediate progression to ESRD, but micro-particle curcumin, a natural health product, has both anti-inflammatory and anti-fibrotic properties and may be an effective treatment for patients with CKD. OBJECTIVE: Micro-particle curcumin for the treatment of CKD-1 (MPAC-CKD-1) will measure the effect of micro-particle curcumin on 2 important markers of CKD progression: albuminuria and estimated glomerular filtration rate (eGFR). Efficacy in either of these markers will justify a larger, international trial to investigate micro-particle curcumin's ability to lower the risk of ESRD in patients with CKD. DESIGN: MPAC-CKD-1 is a multicenter, double-blind prospective randomized controlled trial. SETTING: Four kidney disease clinics in Ontario, Canada (3 in London and 1 in Hamilton). PATIENTS: We will enroll patients with CKD, defined by an eGFR between 15 and 60 mL/min/1.73 m2 and a daily albumin excretion of more than 300 mg (or a random urine sample albumin-to-creatinine ratio more than 30 mg/mmol). MEASUREMENTS: We will measure changes in the co-primary outcomes of urinary albumin-to-creatinine ratio and eGFR at 3 months and 6 months. We will also measure compliance, safety parameters, and changes in health-related quality of life. METHODS: Participants will be randomly assigned to receive micro-particle curcumin 90 mg once daily or matching placebo for 6 months. We will enroll at least 500 patients to exclude clinically meaningful 6-month changes in these 2 co-primary outcomes (16% difference in albuminuria, and a 2.3 mL/min/1.73 m2 between-group difference in the 6-month change in eGFR, at a two-tailed alpha of 0.025, power of 0.80). RESULTS: Patient enrollment began on October 1, 2015, with 414 participants randomized as of July 2018. We expect to report the results in 2020. LIMITATIONS: MPAC-CKD-1 is not powered to assess outcomes such as the need for renal replacement therapy or death. CONCLUSIONS: MPAC-CKD-1 is a multicenter, double-blind prospective randomized controlled trial designed to test whether micro-particle curcumin reduces albuminuria and slows eGFR decline in patients with albuminuric CKD. MPAC-CKD-1 will also test the feasibility of this intervention and inform the need for a future larger scale trial (MPAC-CKD-2). TRIAL REGISTRATION: MPAC-CKD-1 is registered with U.S. National Institutes of Health at clinicaltrials.gov (NCT02369549). Protocol version 2.0, December 6, 2014.

CONTEXTE: La progression vers l'insuffisance rénale terminale (IRT) est la plus importante complication de l'insuffisance rénale chronique (IRC). Les patients atteints d'IRT dépendent de la dialyse ou de la transplantation pour survivre. Ces patients subissent de nombreuses complications et font face à des taux de mortalité très élevés. Ralentir la progression de la maladie est un objectif majeur. Malheureusement, même lorsque les traitements sont prodigués correctement, certains patients atteints de néphropathie chronique progressent vers l'IRT. Les traitements actuels ne parviennent pas à réduire l'inflammation et la fibrose qui médient cette progression. Les microparticules de curcumine, un produit de santé naturel qui possède des propriétés anti-inflammatoire et anti-fibrotiques, pourraient s'avérer un traitement efficace pour les patients atteints d'IRC. OBJECTIF: L'étude MPAC-CKD-1 mesurera l'effet des microparticules de curcumine sur deux marqueurs importants de la progression de la maladie : l'albuminurie et le débit de filtration glomérulaire estimé (DFGe). L'efficacité des microparticules de curcumine sur l'un ou l'autre de ces marqueurs justifiera la conduite d'un essai international à plus grande échelle qui étudiera leur capacité à réduire le risque de progression vers l'IRT chez les patients atteints d'IRC. TYPE D'ÉTUDE: L'étude MPAC-CKD-1 est un essai multicentrique prospectif, contrôlé, à répartition aléatoire et à double insu. CADRE: Quatre cliniques spécialisées en néphropathie de l'Ontario, au Canada (trois à London et une à Hamilton). SUJETS: Seront recrutés les patients atteints d'IRC dont le DFGe se situe entre 15 et 60 ml/min/1,73 m2 et l'excrétion d'albumine quotidienne à plus de 300 mg (ou dont un échantillon d'urine présente un rapport albumine/créatinine de plus de 30 mg/mmol). MESURES: Les changements dans les deux principaux résultats (DFGe et rapport albumine/créatinine urinaire) seront mesurés à trois mois et à six mois. Seront également mesurés la conformité, les paramètres relatifs à l'innocuité et les changements dans la qualité de vie du patient en lien avec sa santé. MÉTHODOLOGIE: Un traitement d'une durée de six mois (dose quotidienne de 90 mg de curcumine ou un placébo) sera attribué de façon aléatoire aux participants. Un minimum de 500 patients sera inclus à l'étude afin d'exclure les changements cliniquement significatifs survenant au cours des six mois pour les deux principaux résultats étudiés (une différence de 16 % de l'albuminurie et une différence de 2,3 ml/min/1,73 m2 du DFGe dans les six mois entre les deux groupes, avec un alpha bilatéral de 0,025 à la puissance 0,80). RÉSULTATS: Le recrutement des patients a débuté le 1er octobre 2015 et en date de juillet 2018, 414 participants avaient été répartis. La publication des résultats est prévue en 2020. LIMITES: L'étude MPAC-CKD-1 n'est pas conçue pour mesurer des résultats tels que le besoin de recourir à une thérapie de remplacement rénal ni pour répertorier le taux de mortalité. CONCLUSION: L'étude MPAC-CKD-1 est un essai multicentrique prospectif, contrôlé, à répartition aléatoire et à double insu, conçu pour mesurer l'effet des microparticules de curcumine chez les patients atteints d'IRC albuminurique. On veut pouvoir observer soit une réduction de l'albuminurie, soit un ralentissement du déclin du DFGe. L'étude MPAC-CKD-1 vise également à tester la faisabilité de cette intervention et à éclairer le besoin de procéder à un essai futur à plus grande échelle (MPAC-CKD-2).

Assessment of habitual physical activity in adolescents with type 1 diabetes.

OBJECTIVE: To evaluate habitual physical activity in a cohort of adolescents with type 1 diabetes in relation to similarly aged control subjects. METHODS: A cross-sectional case control study of 54 healthy adolescents and 66 patients with type 1 diabetes, 14 to 18 years of age, was conducted. Subjects were surveyed using the Habitual Activity Estimation Scale, a validated self-report instrument to assess activity levels in teens. Subjects' time was classified into categories ranging from inactive (lying down, resting) to very active (increased heart rate and diaphoresis). Active time, described in relative (%) and absolute hours per day was determined for each individual. Age, sex, weight, height and body mass index were recorded for all participants, and the charts of subjects with type 1 diabetes were reviewed for most recent levels of glycated hemoglobin, low-density lipoproteins, high-density lipoproteins, total cholesterol, triglycerides and blood pressure. A regression analysis was performed to determine factors associated with hours spent being active. RESULTS: Subjects with type 1 diabetes spent similar hours being very active (3.4 hours vs. 3.5 hours, p=0.49) but reported more time being inactive than controls (2.0 hours vs. 1.3 hours, p=0.002). In both groups, female gender was associated with more hours spent being active. Metabolic control as assessed by glycated hemoglobin worsened with activity. In the group with type 1 diabetes, more hours spent being active were associated with lower systolic blood pressure, lower serum triglyceride levels, lower total cholesterol and higher high-density lipoproteins, whereas inactivity correlated with higher low-density lipoproteins and total cholesterol. CONCLUSIONS: Adolescents with type 1 diabetes reported significantly more time being inactive than did healthy controls. In patients with type 1 diabetes, activity was associated with improved cardiovascular risk profile.

Kidney function after off-pump or on-pump coronary artery bypass graft surgery: a randomized clinical trial.

IMPORTANCE: Most acute kidney injury observed in the hospital is defined by sudden mild or moderate increases in the serum creatinine concentration, which may persist for several days. Such acute kidney injury is associated with lower long-term kidney function. However, it has not been demonstrated that an intervention that reduces the risk of such acute kidney injury better preserves long-term kidney function. OBJECTIVES: To characterize the risk of acute kidney injury with an intervention in a randomized clinical trial and to determine if there is a difference between the 2 treatment groups in kidney function 1 year later. DESIGN, SETTING, AND PARTICIPANTS: The Coronary Artery Bypass Grafting Surgery Off- or On-pump Revascularisation Study (CORONARY) enrolled 4752 patients undergoing first isolated coronary artery bypass graft (CABG) surgery at 79 sites in 19 countries. Patients were randomized to receive CABG surgery either with a beating-heart technique (off-pump) or with cardiopulmonary bypass (on-pump). From January 2010 to November 2011, 2932 patients (from 63 sites in 16 countries) from CORONARY were enrolled into a kidney function substudy to record serum creatinine concentrations during the postoperative period and at 1 year. The last 1-year serum creatinine concentration was recorded on January 18, 2013. MAIN OUTCOMES AND MEASURES: Acute kidney injury within 30 days of surgery (≥50% increase in serum creatinine concentration from prerandomization concentration) and loss of kidney function at 1 year (≥20% loss in estimated glomerular filtration rate from prerandomization level). RESULTS: Off-pump (n = 1472) vs on-pump (n = 1460) CABG surgery reduced the risk of acute kidney injury (17.5% vs 20.8%, respectively; relative risk, 0.83 [95% CI, 0.72-0.97], P = .01); however, there was no significant difference between the 2 groups in the loss of kidney function at 1 year (17.1% vs 15.3%, respectively; relative risk, 1.10 [95% CI, 0.95-1.29], P = .23). Results were consistent with multiple alternate continuous and categorical definitions of acute kidney injury or kidney function loss, and in the subgroup with baseline chronic kidney disease. CONCLUSIONS AND RELEVANCE: Use of off-pump compared with on-pump CABG surgery reduced the risk of postoperative acute kidney injury, without evidence of better preserved kidney function with off-pump CABG surgery at 1 year. In this setting, an intervention that reduced the risk of mild to moderate acute kidney injury did not alter longer-term kidney function. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00463294.

Availability of renal literature in six bibliographic databases.

BACKGROUND: When searching for renal literature, nephrologists must choose between several different bibliographic databases. We compared the availability of renal clinical studies in six major bibliographic databases. METHODS: We gathered 151 renal systematic reviews, which collectively contained 2195 unique citations referencing primary studies in the form of journal articles, meeting articles or meeting abstracts published between 1963 and 2008. We searched for each citation in three subscription-free bibliographic databases (PubMed, Google Scholar and Scirus) and three subscription-based databases (EMBASE, Ovid-MEDLINE and ISI Web of Knowledge). For the subscription-free databases, we determined which full-text journal articles were available free of charge via links to the article source. RESULTS: The proportion of journal articles contained within each of the six databases ranged from 96 to 97%; results were similar for meeting articles. Availability of meeting abstracts was poor, ranging from 0 to 37% (P < 0.01) with ISI Web of Knowledge containing the largest proportion [37%, 95% confidence interval (95% CI) 32-43%]. Among the subscription-free databases, free access to full-text articles was highest in Google Scholar (38% free, 95% CI 36-41%), and was only marginally higher (39%) when all subscription-free databases were searched. After 2000, free access to full-text articles increased to 49%. CONCLUSIONS: Over 99% of renal clinical journal articles are available in at least one major bibliographic database. Subscription-free databases provide free full-text access to almost half of the articles published after the year 2000, which may be of particular interest to clinicians in settings with limited access to subscription-based resources.

Effects of funding policy changes and health warnings on the use of erythropoiesis-stimulating agents.

PURPOSE: To characterize the effects of formulary changes and governmental safety warnings on use of erythropoiesis-stimulating agents (ESAs) in patients with cancer. PATIENTS AND METHODS: We conducted a cross-sectional time-series analysis using health administrative data from Ontario, Canada. From January 1997 to December 2009 we identified all ESA initiations among patients diagnosed with cancer. We explored the effects of two formulary changes that progressively liberalized coverage for ESAs, first by rescinding the requirement for blood transfusion in 2003 and then by removing all restrictions in 2007. We also explored the effect of US Food and Drug Administration and Health Canada warnings issued in the second quarter of 2007. To assess regional variability in ESA use, we determined prescription rates for each of Ontario's 14 regional cancer centers. RESULTS: After the first formulary change, the ESA initiation rate increased to 1.66 new users per 1,000 patients with cancer, 374% more than predicted (P < .001). After the second formulary change, the initiation rate increased to 3.97 new users per 1,000 patients with cancer, 73% more than predicted (P < .001). After the safety warnings, this rate declined 81% by study end (P < .001). We found significant regional variation in ESA use. CONCLUSION: Formulary access and safety warnings had significant impacts on the new use of ESA drugs in patients with cancer. This suggests that both are effective means of influencing the use of these drugs. Variable ESA prescription rates across our region may reflect a lack of consensus regarding their utility.

Coronary Artery Bypass Grafting Surgery Off- or On-pump Revascularisation Study (CORONARY): kidney substudy analytic protocol of an international randomised controlled trial.

INTRODUCTION: CORONARY is a large international randomised controlled trial comparing coronary artery bypass graft (CABG) surgery done with and without a bypass pump. Compared with on-pump, off-pump surgery may prevent acute kidney injury (AKI) in the short term and may better preserve kidney function 1 year following surgery. Secondary analyses may also clarify whether effects are similar in patients with and without pre-operative chronic kidney disease and whether AKI avoidance mediates preserved 1-year kidney function. METHODS AND ANALYSIS: With respect to the study schedule, the last of 4752 patients from 79 sites in 19 countries were randomised in November 2011 to cardiac surgery performed with an on-pump or off-pump procedure. The authors will use regression models to compare the groups in the outcome of peri-operative AKI (per cent change in serum creatinine, ≥50% increase in serum creatinine) and 1-year kidney function (per cent change in estimated glomerular filtration rate (eGFR), ≥20% eGFR loss 1 year after surgery). The authors will use interaction terms in regression models to determine if there is a differential impact of the intervention in those with and without pre-existing chronic kidney disease. The authors will use regression-based tests to determine the proportion of the total effect of surgery type (off-pump vs on-pump CABG) on 1-year eGFR that is mediated by peri-operative AKI. ETHICS AND DISSEMINATION: In the year 2009, the authors were competitively awarded a grant from the Canadian Institutes of Health Research to answer these kidney questions in CORONARY. Ethics approval was obtained for additional renal data collection in centres that agreed to study participation (>90% of participating centres). This collection began for patients enrolled after 1 January 2010. Remaining 1-year renal outcome data will be collected throughout 2012. Results will be reported in 2013. CLINICAL TRIAL REGISTRATION NUMBER: NCT 00463294.

Reporting of the estimated glomerular filtration rate was associated with increased use of angiotensin-converting enzyme inhibitors and angiotensin-II receptor blockers in CKD.

Many guidelines suggest that angiotensin-converting enzyme inhibitors and angiotensin-II receptor antagonists (collectively referred to as renin, angiotensin, aldosterone system blockers (RAAS blockers)) are the preferred treatment for hypertension in most patients with chronic kidney disease (CKD). Improving the recognition of CKD with the introduction of eGFR reporting was intended to have more patients recognized with and treated for this disease. To quantify this, we examined trends in RAAS-blocker use over an 88-month period before and after routine eGFR reporting in southwestern Ontario, Canada. An intervention analysis with seasonal time-series modeling on linked health administrative data for 45,361 ambulatory residents with CKD (eGFR stages 3-5) older than 65 years was performed with a primary outcome of RAAS-blocker usage. The reporting of eGFR was associated with a significant increase in the use of RAAS blockers, as the prescription rate was 571 per 1000 patients with CKD prior to reporting but improved to 607 per 1000 after reporting. There was a significant increase in RAAS-blocker use attributable to eGFR reporting of 19 per 1000 CKD patients. Since about 8% of the adult population has CKD, this equates to about 15,200 new patients receiving RAAS-blocker treatment by 1 year after the introduction of eGFR reporting in community laboratories. Thus, eGFR reporting contributes to improved, guideline-appropriate care of older patients with CKD.

Intensive hemodialysis associates with improved survival compared with conventional hemodialysis.

Patients undergoing conventional maintenance hemodialysis typically receive three sessions per week, each lasting 2.5-5.5 hours. Recently, the use of more intensive hemodialysis (>5.5 hours, three to seven times per week) has increased, but the effects of these regimens on survival are uncertain. We conducted a retrospective cohort study to examine whether intensive hemodialysis associates with better survival than conventional hemodialysis. We identified 420 patients in the International Quotidian Dialysis Registry who received intensive home hemodialysis in France, the United States, and Canada between January 2000 and August 2010. We matched 338 of these patients to 1388 patients in the Dialysis Outcomes and Practice Patterns Study who received in-center conventional hemodialysis during the same time period by country, ESRD duration, and propensity score. The intensive hemodialysis group received a mean (SD) 4.8 (1.1) sessions per week with a mean treatment time of 7.4 (0.87) hours per session; the conventional group received three sessions per week with a mean treatment time of 3.9 (0.32) hours per session. During 3008 patient-years of follow-up, 45 (13%) of 338 patients receiving intensive hemodialysis died compared with 293 (21%) of 1388 patients receiving conventional hemodialysis (6.1 versus 10.5 deaths per 100 person-years; hazard ratio, 0.55 [95% confidence interval, 0.34-0.87]). The strength and direction of the observed association between intensive hemodialysis and improved survival were consistent across all prespecified subgroups and sensitivity analyses. In conclusion, there is a strong association between intensive home hemodialysis and improved survival, but whether this relationship is causal remains unknown.

Validity of administrative database coding for kidney disease: a systematic review.

BACKGROUND: Information in health administrative databases increasingly guides renal care and policy. STUDY DESIGN: Systematic review of observational studies. SETTING & POPULATION: Studies describing the validity of codes for acute kidney injury (AKI) and chronic kidney disease (CKD) in administrative databases operating in any jurisdiction. SELECTION CRITERIA: After searching 13 medical databases, we included observational studies published from database inception though June 2009 that validated renal diagnostic and procedural codes for AKI or CKD against a reference standard. INDEX TESTS: Renal diagnostic or procedural administrative data codes. REFERENCE TESTS: Patient chart review, laboratory values, or data from a high-quality patient registry. RESULTS: 25 studies of 13 databases in 4 countries were included. Validation of diagnostic and procedural codes for AKI was present in 9 studies, and validation for CKD was present in 19 studies. Sensitivity varied across studies and generally was poor (AKI median, 29%; range, 15%-81%; CKD median, 41%; range, 3%-88%). Positive predictive values often were reasonable, but results also were variable (AKI median, 67%; range, 15%-96%; CKD median, 78%; range, 29%-100%). Defining AKI and CKD by only the use of dialysis generally resulted in better code validity. The study characteristic associated with sensitivity in multivariable meta-regression was whether the reference standard used laboratory values (P < 0.001); sensitivity was 39% lower when laboratory values were used (95% CI, 23%-56%). LIMITATIONS: Missing data in primary studies limited some of the analyses that could be done. CONCLUSIONS: Administrative database analyses have utility, but must be conducted and interpreted judiciously to avoid bias arising from poor code validity.