Paul Komenda - Academia.edu (original) (raw)

Papers by Paul Komenda

Research paper thumbnail of An Economic Assessment Model of Rural and Remote Satellite Hemodialysis Units

PloS one, 2015

Kidney Failure is epidemic in many remote communities in Canada. In-centre hemodialysis is provid... more Kidney Failure is epidemic in many remote communities in Canada. In-centre hemodialysis is provided within these settings in satellite hemodialysis units. The key cost drivers of this program have not been fully described. Such information is important in informing the design of programs aimed at optimizing efficiency in providing dialysis and preventative chronic kidney disease care in remote communities. We constructed a cost model based on data derived from 16 of Manitoba, Canada's remote satellite units. We included all costs for operation of the unit, transportation, treatment, and capital costs. All costs were presented in 2013 Canadian dollars. The annual per-patient cost of providing hemodialysis in the satellite units ranged from 80,372to80,372 to 80,372to215,918 per patient, per year. The median per patient, per year cost was 99,888(IQR99,888 (IQR 99,888(IQR89,057-$122,640). Primary cost drivers were capital costs related to construction, human resource expenses, and expenses for return to tertiary c...

Research paper thumbnail of Frailty and physical function in chronic kidney disease: the CanFIT study

Canadian journal of kidney health and disease, 2015

Frailty, a manifestation of unsuccessful aging, is highly prevalent in people with chronic kidney... more Frailty, a manifestation of unsuccessful aging, is highly prevalent in people with chronic kidney disease (CKD) and is associated with comorbid conditions in cross-sectional studies. Longitudinal studies investigating the progression of frailty in those with advanced non-dialysis CKD are lacking. Canadian Frailty Observation and Interventions Trial (CanFIT). To determine the natural history, prevalence of perceived and measured frailty and its association with dialysis treatment choices and adverse outcomes in patients with advanced CKD. Longitudinal observational study, designed to collect data from 600 participants over 2 years. Interprofessional non-dialysis CKD clinics at four tertiary health care centres in central Canada. People with CKD stage 4 and 5 (eGFR <30 ml/min/1.73 m(2)) who are not on dialysis at enrollment. Multiple Frailty Definitions: Short Physical Performance Battery (SPPB), Fried Frailty Criteria, Frailty Index. Dialysis start: In-Centre Hemodialysis, Home He...

Research paper thumbnail of Urinary, Plasma, and Serum Biomarkers’ Utility for Predicting Acute Kidney Injury Associated With Cardiac Surgery in Adults: A Meta-analysis

American Journal of Kidney Diseases, 2015

Early accurate detection of acute kidney injury (AKI) occurring after cardiac surgery may improve... more Early accurate detection of acute kidney injury (AKI) occurring after cardiac surgery may improve morbidity and mortality. Although several novel biomarkers have been developed for the early detection of AKI, their clinical utility in the critical intraoperative and immediate postoperative period remains unclear. Systematic review and meta-analysis. Adult patients having cardiac surgery. EMBASE, CINAHL, Cochrane Library, Scopus, and PubMed from January 1990 until January 2015 were systematically searched for cohort studies reporting the utility of novel biomarkers for the early diagnosis of AKI after adult cardiac surgery. Reviewers extracted data for study design, population, timing of biomarker measurement and AKI occurrence, biomarker performance (area under the receiver operating characteristic curve [AUROC]), and risk of bias. Novel urine, plasma, and serum AKI biomarkers, measured intraoperatively and in the early postoperative period (&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;24 hours). AKI was defined according to the RIFLE, AKIN, or 2012 KDIGO criteria. We found 28 studies reporting intraoperative and/or early postoperative measurement of urine (n=23 studies) or plasma or serum (n=12 studies) biomarkers. Only 4 of these studies measured biomarkers intraoperatively. Overall, intraoperative discrimination by the urine biomarkers neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury marker 1 (KIM-1) demonstrated AUROCs&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.70, whereas N-acetyl-β-d-glucosaminidase (NAG) and cystatin C had AUROCs&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.75. In the immediate 24-hour postoperative period, the urine biomarkers NGAL (16 studies), KIM-1 (6 studies), and liver-type fatty acid binding protein (6 studies) exhibited composite AUROCs of 0.69 to 0.72. The composite AUROCs for postoperative urine cystatin C, NAG, and interleukin 18 were ≤0.70. Similarly, the composite AUROCs for postoperative plasma NGAL (6 studies) and cystatin-C (5 studies) were &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.70. Heterogeneous AKI definitions. In adults, known urinary, plasma, and serum biomarkers of AKI possess modest discrimination at best when measured within 24 hours of cardiac surgery.

Research paper thumbnail of Chronic kidney disease and heart disease: after 179 years, do we yet understand the link?

Kidney international, 2015

A definitive understanding of the link between heart and kidney disease remains elusive. Bittenco... more A definitive understanding of the link between heart and kidney disease remains elusive. Bittencourt et al. explore the association between chronic kidney disease (CKD) status, severity of coronary lesions, and clinical outcome in more than 1500 consecutive adult subjects who underwent a clinically indicated coronary computed tomography angiography for the evaluation of the coronary disease. We discuss the implications of their findings in the context of our current understanding of the development of heart disease in CKD.

Research paper thumbnail of Cystatin C as a biomarker for estimating glomerular filtration rate

Current Opinion in Nephrology and Hypertension, 2015

Glomerular filtration rate (GFR) is rarely measured in clinical practice because of the complexit... more Glomerular filtration rate (GFR) is rarely measured in clinical practice because of the complexity of the measurement. As such, kidney function is typically estimated using validated study equations, which use readily available data including age, sex, race, and serum creatinine as filtration marker. Contemporary research suggests that cystatin C may be an improved alternative to creatinine for inclusion in GFR estimating equations. The purpose of this article is to evaluate the benefits and limitations of using cystatin C as a biomarker of filtration. Cystatin C has fewer non-GFR determinants, when compared with serum creatinine. Use of serum cystatin C avoids the limitations related to both diet and muscle mass that affect serum creatinine. Cystatin C may be more accurate than serum creatinine in estimating GFR, and is more strongly associated with all-cause mortality and cardiovascular events. Cystatin C has some advantages over serum creatinine in estimating GFR. The use of cystatin C as a confirmatory biomarker in deciding medication dosages or as a confirmatory test in patients with an uncertain diagnosis of chronic kidney disease may be beneficial.

Research paper thumbnail of The Authors Reply

Kidney International, 2010

Research paper thumbnail of A Microfluidic Platform for Evaluating Neutrophil Chemotaxis Induced by Sputum from COPD Patients

PloS one, 2015

Chronic Obstructive Pulmonary Disease (COPD) is a common lung disease characterized by breathing ... more Chronic Obstructive Pulmonary Disease (COPD) is a common lung disease characterized by breathing difficulty as a consequence of narrowed airways. Previous studies have shown that COPD is correlated with neutrophil infiltration into the airways through chemotactic migration. However, whether neutrophil chemotaxis can be used to characterize and diagnose COPD is not well established. In the present study, we developed a microfluidic platform for evaluating neutrophil chemotaxis to sputum samples from COPD patients. Our results show increased neutrophil chemotaxis to COPD sputum compared to control sputum from healthy individuals. The level of COPD sputum induced neutrophil chemotaxis was correlated with the patient's spirometry data. The cell morphology of neutrophils in a COPD sputum gradient is similar to the morphology displayed by neutrophils exposed to an IL-8 gradient, but not a fMLP gradient. In competing gradients of COPD sputum and fMLP, neutrophils chemotaxis and cell mo...

Research paper thumbnail of Secular trends in end-stage renal disease requiring dialysis in Manitoba, Canada: a population-based study

CMAJ open

End-stage renal disease (ESRD) requiring dialysis is expensive and is associated with disproporti... more End-stage renal disease (ESRD) requiring dialysis is expensive and is associated with disproportionately poor health outcomes and quality of life. Understanding regional long-term secular trends in the incidence and prevalence of dialysis will allow for the alignment of appropriate and efficient delivery of care. The primary objective of this study was to describe long-term secular and geographic trends in ESRD over a 22-year period in a single-provider Canadian health care setting. Using a previously validated case definition, we described the annual incidence and prevalence of ESRD in Manitoba from 1989 to 2010, stratified by age, sex and geographic location within the province. We searched more than 1.2 million records within the Manitoba Health repository. We identified 9489 patients in the Manitoba Health Physician Claims database with at least 1 claim for dialysis from 1989 through Mar. 31, 2010. Using the case definition of any 2 dialysis treatment claims, the total annual in...

Research paper thumbnail of Evaluating the implementation strategy for estimated glomerular filtration rate reporting in Manitoba: the effect on referral numbers, wait times, and appropriateness of consults

Canadian journal of kidney health and disease, 2014

Chronic kidney disease screening using estimated glomerular filtration rate (eGFR) reporting is s... more Chronic kidney disease screening using estimated glomerular filtration rate (eGFR) reporting is standard in many regions. With its implementation, many centres have had higher referral rates and increased wait times to see nephrologists. Manitoba began eGFR reporting in October 2010. We measured the effect of eGFR reporting on referral rates, wait times, and appropriateness of referrals after an educational intervention. An interrupted time series design was used. This study took place in Manitoba, Canada. All referrals to the Manitoba Renal Program in the period prior to eGFR reporting between April 1, 2010 and September 30, 2010 were compared with a post period between January 1, 2011 and June 30, 2011. Data on demographics, co-morbidities, referral numbers and wait times were compared between periods. Appropriateness of consults was also measured after eGFR implementation. Prior to eGFR reporting, primary care physicians underwent educational interventions on eGFR interpretation ...

Research paper thumbnail of Trends in Arteriovenous Fistula Use at Dialysis Initiation After Automated eGFR Reporting

Seminars in dialysis, Jan 12, 2015

The purpose of this study was to examine trends in the presence of an arteriovenous fistula (AVF)... more The purpose of this study was to examine trends in the presence of an arteriovenous fistula (AVF) at dialysis initiation before and after eGFR reporting. All incident dialysis patients from four Canadian provinces that implemented province-wide, automated laboratory reporting of eGFR with known vascular access at dialysis initiation were included in the study (N = 25,201) from 2001 to 2010. The primary outcome was the change in proportion of patients with an AVF at dialysis initiation using an interrupted time series and adjusted multilevel logistic regression models. AVF usage at dialysis initiation decreased gradually over the study period from 19.0% to 14.6%. After implementation of automated eGFR reporting, there was attenuation in the decline in AVF usage in models adjusted for case-mix, facility, and the downward trajectory in AVF use over time. The adjusted odds ratio for initiating dialysis with an AVF 1 year post-eGFR reporting compared to pre-eGFR reporting was more pronou...

Research paper thumbnail of The evaluation of a successful home hemodialysis program: establishing a prospective framework for quality

Clinical nephrology, 2009

A mounting body of clinical data and purported quality of life benefits has been primarily respon... more A mounting body of clinical data and purported quality of life benefits has been primarily responsible for a renewed interest in programs providing longer more frequent home hemodialysis. As novel forms of home hemodialysis (HHD) like nocturnal (nightly) home hemodialysis (NHD) move from strictly the academic "experimental" arenas to potentially the preferred renal replacement modality for patients, it will be necessary for programs to plan and evaluate standardized metrics for program quality. This will be essential for smaller, less experienced centers to gauge their outcomes against larger, more established programs. Driven by market forces primarily in the United States, conventional hemodialysis programs have begun to explore optimal strategies for reporting quality of care in their respective dialysis centers. Extrapolating this to home hemodialysis modalities the question remains which criteria do we use as measures of quality? The evidence is limited to small, obse...

Research paper thumbnail of Improving the Quality and Efficiency of Conventional In-center Hemodialysis

Seminars in Dialysis, 2015

There is substantial variability at international, national, and regional levels in how effective... more There is substantial variability at international, national, and regional levels in how effective dialysis providers are in the implementation of well-accepted interventions to deliver better health outcomes at reduced costs to payers. The growing number of dialysis patients within a finite pool of resources has led to searches for more efficient methods to provide patient care without compromising or diminishing quality. We review here some contemporary concepts surrounding quality improvement and operations research that may provide clinician administrators to both improve efficiency and quality in facility based hemodialysis units. The creation of balanced scorecards, utilization of process mapping techniques, and the application of LEAN principles may readily improve how hemodialysis care is delivered in an environment of increasing patient volumes and reduced operating resources.

Research paper thumbnail of Geographic and facility-level variation in the use of peritoneal dialysis in Canada: a cohort study

Research paper thumbnail of Cardiovascular remodeling during long-term nocturnal home hemodialysis

Clinical and Experimental Nephrology, 2014

Background Cardiovascular disease is the leading cause of morbidity and mortality in patients wit... more Background Cardiovascular disease is the leading cause of morbidity and mortality in patients with kidney failure. Nocturnal home hemodialysis (NHD) is a form of kidney replacement therapy whereby hemodialysis is performed for at least 6-h overnight, at least 4 days per week. Little is known about the effects of NHD on cardiovascular remodeling as assessed by transthoracic echocardiography (TTE) and cardiac magnetic resonance imaging (CMR). Objectives The primary objective of the study was to determine the long-term effects of NHD on cardiovascular remodeling using different imaging modalities over a oneyear follow-up. Methods and results A total of 11 patients were included in the study (6 males, mean age 48 ± 16 years) between 2009 and 2011 inclusive at a single tertiary care center. All patients underwent TTE and CMR at baseline and after 1 year of NHD. Left ventricular mass index decreased significantly at 1 year by both TTE (152 ± 7-129 ± 8 g/ m 2 , p \ 0.05) and CMR (162 ± 4-124 ± 4 g/m 2 , p \ 0.05). There was also a significant decrease in both left and right atrial volume as well as in right ventricular mass index over 1 year of follow-up. Diastolic dysfunction, graded from 0 to 4, improved from a baseline grade of 3.4 to 1.2 at 1-year follow-up. Conclusions Long-term nocturnal hemodialysis leads to favorable cardiovascular remodeling with a reduction in cavity dimensions, regression of left ventricular hypertrophy, and an improvement in diastolic function, as assessed by both TTE and CMR.

Research paper thumbnail of Cost-effective treatment modalities for reducing morbidity associated with chronic kidney disease

Expert review of pharmacoeconomics & outcomes research, Jan 8, 2015

Chronic kidney disease (CKD) is a worldwide health problem with increasing prevalence and inciden... more Chronic kidney disease (CKD) is a worldwide health problem with increasing prevalence and incidence. Guidelines suggest that early referral to a nephrologist to manage advanced stage (4+) patients with CKD is an effective treatment strategy, with earlier stage patients best managed through primary care physicians. Should patients with CKD progress to total kidney failure, several therapies are available that vary widely in costs. Kidney transplantation offers the lowest costs and highest quality of life, followed in ascending order of costs by peritoneal dialysis, home hemodialysis and facility-based hemodialysis. Earlier detection of CKD may prevent progression to kidney failure, and accurate risk prediction of end-stage kidney failure may improve clinical planning, outcomes and resource allocation.

Research paper thumbnail of Programmatic variation in home hemodialysis in Canada: results from a nationwide survey of practice patterns

Canadian Journal of Kidney Health and Disease, 2014

Background: Over 40% of patients with end stage renal disease in the United States were treated w... more Background: Over 40% of patients with end stage renal disease in the United States were treated with home hemodialysis (HHD) in the early 1970's. However, this number declined rapidly over the ensuing decades so that the overwhelming majority of patients were treated in-centre 3 times per week on a 3-4 hour schedule. Poor outcomes for patients treated in this fashion led to a renewed interest in home hemodialysis, with more intensive dialysis schedules including short daily (SDHD) and nocturnal (NHD). The relative infancy of these treatment schedules means that there is a paucity of data on 'how to do it'.

Research paper thumbnail of PATIENT AND FACILITY-LEVEL VARIATION IN THE TIMING OF DIALYSIS INITIATION ACROSS CANADA: CANADIAN KIDNEY KNOWLEDGE TRANSLATION AND GENERATION NETWORK (CANN-NET)

Research paper thumbnail of Current Issue Highlights

Research paper thumbnail of Mortality risk for women on chronic hemodialysis differs by age

Canadian Journal of Kidney Health and Disease, 2014

Background: Previous reports have demonstrated similar survival for men and women on hemodialysis... more Background: Previous reports have demonstrated similar survival for men and women on hemodialysis, despite women's increased survival in the general population.

Research paper thumbnail of The urea to creatinine ratio is predictive of worsening kidney function in ambulatory heart failure patients

Journal of Cardiac Failure, 2015

Background: Changes in kidney function in heart failure patients conveys important prognostic inf... more Background: Changes in kidney function in heart failure patients conveys important prognostic information. We investigated the association of the urea to creatinine (UCr) ratio, the fractional excretion of urea (FeUrea) and the fractional excretion of sodium (FeNa) and subsequent declines in kidney function in ambulatory heart failure patients.

Research paper thumbnail of An Economic Assessment Model of Rural and Remote Satellite Hemodialysis Units

PloS one, 2015

Kidney Failure is epidemic in many remote communities in Canada. In-centre hemodialysis is provid... more Kidney Failure is epidemic in many remote communities in Canada. In-centre hemodialysis is provided within these settings in satellite hemodialysis units. The key cost drivers of this program have not been fully described. Such information is important in informing the design of programs aimed at optimizing efficiency in providing dialysis and preventative chronic kidney disease care in remote communities. We constructed a cost model based on data derived from 16 of Manitoba, Canada's remote satellite units. We included all costs for operation of the unit, transportation, treatment, and capital costs. All costs were presented in 2013 Canadian dollars. The annual per-patient cost of providing hemodialysis in the satellite units ranged from 80,372to80,372 to 80,372to215,918 per patient, per year. The median per patient, per year cost was 99,888(IQR99,888 (IQR 99,888(IQR89,057-$122,640). Primary cost drivers were capital costs related to construction, human resource expenses, and expenses for return to tertiary c...

Research paper thumbnail of Frailty and physical function in chronic kidney disease: the CanFIT study

Canadian journal of kidney health and disease, 2015

Frailty, a manifestation of unsuccessful aging, is highly prevalent in people with chronic kidney... more Frailty, a manifestation of unsuccessful aging, is highly prevalent in people with chronic kidney disease (CKD) and is associated with comorbid conditions in cross-sectional studies. Longitudinal studies investigating the progression of frailty in those with advanced non-dialysis CKD are lacking. Canadian Frailty Observation and Interventions Trial (CanFIT). To determine the natural history, prevalence of perceived and measured frailty and its association with dialysis treatment choices and adverse outcomes in patients with advanced CKD. Longitudinal observational study, designed to collect data from 600 participants over 2 years. Interprofessional non-dialysis CKD clinics at four tertiary health care centres in central Canada. People with CKD stage 4 and 5 (eGFR <30 ml/min/1.73 m(2)) who are not on dialysis at enrollment. Multiple Frailty Definitions: Short Physical Performance Battery (SPPB), Fried Frailty Criteria, Frailty Index. Dialysis start: In-Centre Hemodialysis, Home He...

Research paper thumbnail of Urinary, Plasma, and Serum Biomarkers’ Utility for Predicting Acute Kidney Injury Associated With Cardiac Surgery in Adults: A Meta-analysis

American Journal of Kidney Diseases, 2015

Early accurate detection of acute kidney injury (AKI) occurring after cardiac surgery may improve... more Early accurate detection of acute kidney injury (AKI) occurring after cardiac surgery may improve morbidity and mortality. Although several novel biomarkers have been developed for the early detection of AKI, their clinical utility in the critical intraoperative and immediate postoperative period remains unclear. Systematic review and meta-analysis. Adult patients having cardiac surgery. EMBASE, CINAHL, Cochrane Library, Scopus, and PubMed from January 1990 until January 2015 were systematically searched for cohort studies reporting the utility of novel biomarkers for the early diagnosis of AKI after adult cardiac surgery. Reviewers extracted data for study design, population, timing of biomarker measurement and AKI occurrence, biomarker performance (area under the receiver operating characteristic curve [AUROC]), and risk of bias. Novel urine, plasma, and serum AKI biomarkers, measured intraoperatively and in the early postoperative period (&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;24 hours). AKI was defined according to the RIFLE, AKIN, or 2012 KDIGO criteria. We found 28 studies reporting intraoperative and/or early postoperative measurement of urine (n=23 studies) or plasma or serum (n=12 studies) biomarkers. Only 4 of these studies measured biomarkers intraoperatively. Overall, intraoperative discrimination by the urine biomarkers neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury marker 1 (KIM-1) demonstrated AUROCs&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.70, whereas N-acetyl-β-d-glucosaminidase (NAG) and cystatin C had AUROCs&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.75. In the immediate 24-hour postoperative period, the urine biomarkers NGAL (16 studies), KIM-1 (6 studies), and liver-type fatty acid binding protein (6 studies) exhibited composite AUROCs of 0.69 to 0.72. The composite AUROCs for postoperative urine cystatin C, NAG, and interleukin 18 were ≤0.70. Similarly, the composite AUROCs for postoperative plasma NGAL (6 studies) and cystatin-C (5 studies) were &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;0.70. Heterogeneous AKI definitions. In adults, known urinary, plasma, and serum biomarkers of AKI possess modest discrimination at best when measured within 24 hours of cardiac surgery.

Research paper thumbnail of Chronic kidney disease and heart disease: after 179 years, do we yet understand the link?

Kidney international, 2015

A definitive understanding of the link between heart and kidney disease remains elusive. Bittenco... more A definitive understanding of the link between heart and kidney disease remains elusive. Bittencourt et al. explore the association between chronic kidney disease (CKD) status, severity of coronary lesions, and clinical outcome in more than 1500 consecutive adult subjects who underwent a clinically indicated coronary computed tomography angiography for the evaluation of the coronary disease. We discuss the implications of their findings in the context of our current understanding of the development of heart disease in CKD.

Research paper thumbnail of Cystatin C as a biomarker for estimating glomerular filtration rate

Current Opinion in Nephrology and Hypertension, 2015

Glomerular filtration rate (GFR) is rarely measured in clinical practice because of the complexit... more Glomerular filtration rate (GFR) is rarely measured in clinical practice because of the complexity of the measurement. As such, kidney function is typically estimated using validated study equations, which use readily available data including age, sex, race, and serum creatinine as filtration marker. Contemporary research suggests that cystatin C may be an improved alternative to creatinine for inclusion in GFR estimating equations. The purpose of this article is to evaluate the benefits and limitations of using cystatin C as a biomarker of filtration. Cystatin C has fewer non-GFR determinants, when compared with serum creatinine. Use of serum cystatin C avoids the limitations related to both diet and muscle mass that affect serum creatinine. Cystatin C may be more accurate than serum creatinine in estimating GFR, and is more strongly associated with all-cause mortality and cardiovascular events. Cystatin C has some advantages over serum creatinine in estimating GFR. The use of cystatin C as a confirmatory biomarker in deciding medication dosages or as a confirmatory test in patients with an uncertain diagnosis of chronic kidney disease may be beneficial.

Research paper thumbnail of The Authors Reply

Kidney International, 2010

Research paper thumbnail of A Microfluidic Platform for Evaluating Neutrophil Chemotaxis Induced by Sputum from COPD Patients

PloS one, 2015

Chronic Obstructive Pulmonary Disease (COPD) is a common lung disease characterized by breathing ... more Chronic Obstructive Pulmonary Disease (COPD) is a common lung disease characterized by breathing difficulty as a consequence of narrowed airways. Previous studies have shown that COPD is correlated with neutrophil infiltration into the airways through chemotactic migration. However, whether neutrophil chemotaxis can be used to characterize and diagnose COPD is not well established. In the present study, we developed a microfluidic platform for evaluating neutrophil chemotaxis to sputum samples from COPD patients. Our results show increased neutrophil chemotaxis to COPD sputum compared to control sputum from healthy individuals. The level of COPD sputum induced neutrophil chemotaxis was correlated with the patient's spirometry data. The cell morphology of neutrophils in a COPD sputum gradient is similar to the morphology displayed by neutrophils exposed to an IL-8 gradient, but not a fMLP gradient. In competing gradients of COPD sputum and fMLP, neutrophils chemotaxis and cell mo...

Research paper thumbnail of Secular trends in end-stage renal disease requiring dialysis in Manitoba, Canada: a population-based study

CMAJ open

End-stage renal disease (ESRD) requiring dialysis is expensive and is associated with disproporti... more End-stage renal disease (ESRD) requiring dialysis is expensive and is associated with disproportionately poor health outcomes and quality of life. Understanding regional long-term secular trends in the incidence and prevalence of dialysis will allow for the alignment of appropriate and efficient delivery of care. The primary objective of this study was to describe long-term secular and geographic trends in ESRD over a 22-year period in a single-provider Canadian health care setting. Using a previously validated case definition, we described the annual incidence and prevalence of ESRD in Manitoba from 1989 to 2010, stratified by age, sex and geographic location within the province. We searched more than 1.2 million records within the Manitoba Health repository. We identified 9489 patients in the Manitoba Health Physician Claims database with at least 1 claim for dialysis from 1989 through Mar. 31, 2010. Using the case definition of any 2 dialysis treatment claims, the total annual in...

Research paper thumbnail of Evaluating the implementation strategy for estimated glomerular filtration rate reporting in Manitoba: the effect on referral numbers, wait times, and appropriateness of consults

Canadian journal of kidney health and disease, 2014

Chronic kidney disease screening using estimated glomerular filtration rate (eGFR) reporting is s... more Chronic kidney disease screening using estimated glomerular filtration rate (eGFR) reporting is standard in many regions. With its implementation, many centres have had higher referral rates and increased wait times to see nephrologists. Manitoba began eGFR reporting in October 2010. We measured the effect of eGFR reporting on referral rates, wait times, and appropriateness of referrals after an educational intervention. An interrupted time series design was used. This study took place in Manitoba, Canada. All referrals to the Manitoba Renal Program in the period prior to eGFR reporting between April 1, 2010 and September 30, 2010 were compared with a post period between January 1, 2011 and June 30, 2011. Data on demographics, co-morbidities, referral numbers and wait times were compared between periods. Appropriateness of consults was also measured after eGFR implementation. Prior to eGFR reporting, primary care physicians underwent educational interventions on eGFR interpretation ...

Research paper thumbnail of Trends in Arteriovenous Fistula Use at Dialysis Initiation After Automated eGFR Reporting

Seminars in dialysis, Jan 12, 2015

The purpose of this study was to examine trends in the presence of an arteriovenous fistula (AVF)... more The purpose of this study was to examine trends in the presence of an arteriovenous fistula (AVF) at dialysis initiation before and after eGFR reporting. All incident dialysis patients from four Canadian provinces that implemented province-wide, automated laboratory reporting of eGFR with known vascular access at dialysis initiation were included in the study (N = 25,201) from 2001 to 2010. The primary outcome was the change in proportion of patients with an AVF at dialysis initiation using an interrupted time series and adjusted multilevel logistic regression models. AVF usage at dialysis initiation decreased gradually over the study period from 19.0% to 14.6%. After implementation of automated eGFR reporting, there was attenuation in the decline in AVF usage in models adjusted for case-mix, facility, and the downward trajectory in AVF use over time. The adjusted odds ratio for initiating dialysis with an AVF 1 year post-eGFR reporting compared to pre-eGFR reporting was more pronou...

Research paper thumbnail of The evaluation of a successful home hemodialysis program: establishing a prospective framework for quality

Clinical nephrology, 2009

A mounting body of clinical data and purported quality of life benefits has been primarily respon... more A mounting body of clinical data and purported quality of life benefits has been primarily responsible for a renewed interest in programs providing longer more frequent home hemodialysis. As novel forms of home hemodialysis (HHD) like nocturnal (nightly) home hemodialysis (NHD) move from strictly the academic "experimental" arenas to potentially the preferred renal replacement modality for patients, it will be necessary for programs to plan and evaluate standardized metrics for program quality. This will be essential for smaller, less experienced centers to gauge their outcomes against larger, more established programs. Driven by market forces primarily in the United States, conventional hemodialysis programs have begun to explore optimal strategies for reporting quality of care in their respective dialysis centers. Extrapolating this to home hemodialysis modalities the question remains which criteria do we use as measures of quality? The evidence is limited to small, obse...

Research paper thumbnail of Improving the Quality and Efficiency of Conventional In-center Hemodialysis

Seminars in Dialysis, 2015

There is substantial variability at international, national, and regional levels in how effective... more There is substantial variability at international, national, and regional levels in how effective dialysis providers are in the implementation of well-accepted interventions to deliver better health outcomes at reduced costs to payers. The growing number of dialysis patients within a finite pool of resources has led to searches for more efficient methods to provide patient care without compromising or diminishing quality. We review here some contemporary concepts surrounding quality improvement and operations research that may provide clinician administrators to both improve efficiency and quality in facility based hemodialysis units. The creation of balanced scorecards, utilization of process mapping techniques, and the application of LEAN principles may readily improve how hemodialysis care is delivered in an environment of increasing patient volumes and reduced operating resources.

Research paper thumbnail of Geographic and facility-level variation in the use of peritoneal dialysis in Canada: a cohort study

Research paper thumbnail of Cardiovascular remodeling during long-term nocturnal home hemodialysis

Clinical and Experimental Nephrology, 2014

Background Cardiovascular disease is the leading cause of morbidity and mortality in patients wit... more Background Cardiovascular disease is the leading cause of morbidity and mortality in patients with kidney failure. Nocturnal home hemodialysis (NHD) is a form of kidney replacement therapy whereby hemodialysis is performed for at least 6-h overnight, at least 4 days per week. Little is known about the effects of NHD on cardiovascular remodeling as assessed by transthoracic echocardiography (TTE) and cardiac magnetic resonance imaging (CMR). Objectives The primary objective of the study was to determine the long-term effects of NHD on cardiovascular remodeling using different imaging modalities over a oneyear follow-up. Methods and results A total of 11 patients were included in the study (6 males, mean age 48 ± 16 years) between 2009 and 2011 inclusive at a single tertiary care center. All patients underwent TTE and CMR at baseline and after 1 year of NHD. Left ventricular mass index decreased significantly at 1 year by both TTE (152 ± 7-129 ± 8 g/ m 2 , p \ 0.05) and CMR (162 ± 4-124 ± 4 g/m 2 , p \ 0.05). There was also a significant decrease in both left and right atrial volume as well as in right ventricular mass index over 1 year of follow-up. Diastolic dysfunction, graded from 0 to 4, improved from a baseline grade of 3.4 to 1.2 at 1-year follow-up. Conclusions Long-term nocturnal hemodialysis leads to favorable cardiovascular remodeling with a reduction in cavity dimensions, regression of left ventricular hypertrophy, and an improvement in diastolic function, as assessed by both TTE and CMR.

Research paper thumbnail of Cost-effective treatment modalities for reducing morbidity associated with chronic kidney disease

Expert review of pharmacoeconomics & outcomes research, Jan 8, 2015

Chronic kidney disease (CKD) is a worldwide health problem with increasing prevalence and inciden... more Chronic kidney disease (CKD) is a worldwide health problem with increasing prevalence and incidence. Guidelines suggest that early referral to a nephrologist to manage advanced stage (4+) patients with CKD is an effective treatment strategy, with earlier stage patients best managed through primary care physicians. Should patients with CKD progress to total kidney failure, several therapies are available that vary widely in costs. Kidney transplantation offers the lowest costs and highest quality of life, followed in ascending order of costs by peritoneal dialysis, home hemodialysis and facility-based hemodialysis. Earlier detection of CKD may prevent progression to kidney failure, and accurate risk prediction of end-stage kidney failure may improve clinical planning, outcomes and resource allocation.

Research paper thumbnail of Programmatic variation in home hemodialysis in Canada: results from a nationwide survey of practice patterns

Canadian Journal of Kidney Health and Disease, 2014

Background: Over 40% of patients with end stage renal disease in the United States were treated w... more Background: Over 40% of patients with end stage renal disease in the United States were treated with home hemodialysis (HHD) in the early 1970's. However, this number declined rapidly over the ensuing decades so that the overwhelming majority of patients were treated in-centre 3 times per week on a 3-4 hour schedule. Poor outcomes for patients treated in this fashion led to a renewed interest in home hemodialysis, with more intensive dialysis schedules including short daily (SDHD) and nocturnal (NHD). The relative infancy of these treatment schedules means that there is a paucity of data on 'how to do it'.

Research paper thumbnail of PATIENT AND FACILITY-LEVEL VARIATION IN THE TIMING OF DIALYSIS INITIATION ACROSS CANADA: CANADIAN KIDNEY KNOWLEDGE TRANSLATION AND GENERATION NETWORK (CANN-NET)

Research paper thumbnail of Current Issue Highlights

Research paper thumbnail of Mortality risk for women on chronic hemodialysis differs by age

Canadian Journal of Kidney Health and Disease, 2014

Background: Previous reports have demonstrated similar survival for men and women on hemodialysis... more Background: Previous reports have demonstrated similar survival for men and women on hemodialysis, despite women's increased survival in the general population.

Research paper thumbnail of The urea to creatinine ratio is predictive of worsening kidney function in ambulatory heart failure patients

Journal of Cardiac Failure, 2015

Background: Changes in kidney function in heart failure patients conveys important prognostic inf... more Background: Changes in kidney function in heart failure patients conveys important prognostic information. We investigated the association of the urea to creatinine (UCr) ratio, the fractional excretion of urea (FeUrea) and the fractional excretion of sodium (FeNa) and subsequent declines in kidney function in ambulatory heart failure patients.