Differences in Antihypertensive Medication Prescription Profiles Between 2009 and 2021: A Retrospective Cohort Study of CARTaGENE

Background

Although blood pressure (BP) control is critical to prevent cardiovascular diseases, hypertension control rates in Canada are in decline.

Objective

To assess this issue, we sought to evaluate the differences in antihypertensive medication prescription profiles in the province of Quebec between 2009 and 2021.

Design

This is a retrospective cohort study.

Setting

We used data from the CARTaGENE population-based cohort linked to administrative health databases.

Patients

Participants with any drug claim in the 6 months prior to the end of follow-up were included.

Measurements

Guideline-recommended antihypertensive drug prescription profiles were assessed at the time of enrollment (2009-2010) and end of follow-up (March 2021).

Methods

Prescriptions practices from the 2 time periods were compared using Pearson's chi-square tests. A sensitivity analysis was performed by excluding participants in which antihypertensive drugs may not have been prescribed solely to treat hypertension (presence of atrial fibrillation/flutter, ischemic heart disease, heart failure, chronic kidney disease, or migraines documented prior to or during follow-up).

Results

Of 8447 participants included in the study, 31.4% and 51.3% filled prescriptions for antihypertensive drugs at the beginning and end of follow-up. In both study periods, guideline-recommended monotherapy was applied in most participants with hypertension (77.9% vs 79.5%, P = .3), whereas optimal 2 and 3-drug combinations were used less frequently (62.0% vs 61.4%, P = .77, 51.9% vs 46.7%, P = .066, respectively). Only the use of long-acting thiazide-like diuretics (9.5% vs 27.7%, P < .001) and spironolactone as a fourth-line agent (8.3% vs 15.9%, P = .054) increased with time but nonetheless remained infrequent. Results were similar in the sensitivity analysis.

Limitations

Specific indication of the prescribed antihypertensive medications and follow-up BP data was not available.

Conclusions

Application of hypertension guidelines for the choice of antihypertensive drugs remains suboptimal, highlighting the need for education initiatives. This may be an important step to raise BP control rates in Canada.

Is health-related quality of life trajectory associated with dialysis modality choice in advanced chronic kidney disease?

BACKGROUND

Patients with advanced chronic kidney disease have lower health-related quality of life (HRQOL) than the general population. There is uncertainty regarding patterns of HRQOL changes before dialysis initiation. This study aimed to characterise HRQOL trajectory and assess its potential association with intended dialysis modality.

METHODS

This prospective single-centre cohort study followed adults with an estimated glomerular filtration rate ≤15 mL/min/1.73 m2 for one year. Patients were allocated into one of two groups based on their intended treatment modality, 'home dialysis' (peritoneal dialysis or home haemodialysis (HD)) and 'other' (in-centre HD or conservative care). Follow-up was for up to 1 year or earlier if initiated on kidney replacement therapy or died. Kidney Disease Quality of Life - Short Form (KDQOL-SF) was completed every 6 months. Predictors of changes in KDQOL-SF components were modelled using mixed effect multivariable linear regressions.

RESULTS

One hundred and nine patients were included. At baseline, crude physical composite summary (PCS) (45 ± 10 vs. 39 ± 8) was higher in patients choosing home dialysis (n = 41), while mental composite summary (MCS) was similar in both groups. After adjustment, patients choosing home dialysis had an increase in MCS (B = 8.4 per year, p = 0.007) compared to those selecting in-centre HD/conservative care. This translates into an annual increase in MSC by 3 points for the 'home dialysis' group, compared to an annual decline by 5.4 points in the 'other' group. There was no difference in PCS trajectory through time.

CONCLUSIONS

Patients choosing home dialysis had improved MCS over time compared to those not selecting home dialysis. More work is needed to determine how differences in processes of care and/or unmeasured patient characteristics modulate this association.

Outcomes of Integrated Home Dialysis Care: Results From the Canadian Organ Replacement Register

RATIONALE & OBJECTIVE

The integrated home dialysis model proposes the initiation of kidney replacement therapy (KRT) with peritoneal dialysis (PD) and a timely transition to home hemodialysis (HHD) after PD ends. We compared the outcomes of patients transitioning from PD to HHD with those initiating KRT with HHD.

STUDY DESIGN

Observational analysis of the Canadian Organ Replacement Register (CORR).

SETTINGS & PARTICIPANTS

All patients who initiated PD or HHD within the first 90 days of KRT between 2005 and 2018.

EXPOSURE

Patients transitioning from PD to HHD (PD+HHD group) versus patients initiating KRT with HHD (HHD group).

OUTCOME

(1) A composite of all-cause mortality and modality transfer (to in-center hemodialysis or PD for 90 days) and (2) all hospitalizations (considered as recurrent events).

ANALYTICAL APPROACH

A propensity score analysis for which PD+HHD patients were matched 1:1 to (1) incident HHD patients ("incident-match" analysis) or (2) HHD patients with a KRT vintage at least equivalent to the vintage of PD+HHD patients at the transition time ("vintage-matched" analysis). Cause-specific hazards models (composite outcome) and shared frailty models (hospitalization) were used to compare groups.

RESULTS

Among 63,327 individuals in the CORR, 163 PD+HHD patients (median of 1.9 years in PD) and 711 HHD patients were identified. In the incident-match analysis, compared to the HHD patients, the PD+HHD group had a similar risk of the composite outcome (HR, 0.88 [95% CI, 0.58-1.32]) and hospitalizations (HR, 1.04 [95% CI, 0.76-1.41]). In the vintage-match analysis, PD+HHD patients had a lower hazard for the composite outcome (HR, 0.61 [95% CI, 0.40-0.94]) but a similar hospitalization risk (HR, 0.85 [95% CI, 0.59-1.24]).

LIMITATIONS

Risk of survivor bias in the PD+HHD cohort and residual confounding.

CONCLUSIONS

Controlling for KRT vintage, the patients transitioning from PD to HHD had better clinical outcomes than the incident HHD patients. These data support the use of integrated home dialysis for patients initiating home-based KRT.

PLAIN-LANGUAGE SUMMARY

The integrated home dialysis model proposes the initiation of dialysis with peritoneal dialysis (PD) and subsequent transition to home hemodialysis (HHD) once PD is no longer feasible. It allows patients to benefit from initial lifestyle advantages of PD and to continue home-based treatments after its termination. However, some patients may prefer to initiate dialysis with HHD from the outset. In this study, we compared the long-term clinical outcomes of both approaches using a large Canadian dialysis register. We found that both options led to a similar risk of hospitalization. In contrast, the PD-to-HHD model led to improved survival when controlling for the duration of kidney failure.

Impact of Successive Office Blood Pressure Measurements During a Single Visit on Cardiovascular Risk Prediction: Analysis of CARTaGENE

BACKGROUND

Multiple office blood pressure (BP) readings correlate more closely with ambulatory BP than single readings. Whether they are associated with long-term outcomes and improve cardiovascular risk prediction is unknown. Our objective was to assess the long-term impact of multiple office BP readings.

METHODS

We used data from CARTaGENE, a population-based survey comprising individuals aged 40 to 70 years. Three BP readings (BP1, BP2, and BP3) at 2-minute intervals were obtained using a semiautomated device. They were averaged to generate BP1-2, BP2-3, and BP1-2-3 for systolic BP (SBP) and diastolic BP. Cardiovascular events (major adverse cardiovascular event [MACE]: cardiovascular death, stroke, and myocardial infarction) during a 10-year follow-up were recorded. Associations with MACE were obtained using adjusted Cox models. Predictive performance was assessed with 10-year atherosclerotic cardiovascular disease scores and their associated C statistics.

RESULTS

In the 17 966 eligible individuals, 2378 experienced a MACE during follow-up. Crude SBP values ranged from 122.5 to 126.5 mm Hg. SBP3 had the strongest association with MACE incidence (hazard ratio, 1.10 [1.05-1.15] per SD) and SBP1 the weakest (hazard ratio, 1.06 [1.01-1.10]). All models including SBP1 (SBP1, SBP1-2, and SBP1-2-3) were underperformed. At a given SBP value, the excess MACE risk conferred by SBP3 was 2× greater than SBP1. In atherosclerotic cardiovascular disease scores, SBP3 yielded the highest C statistic, significantly higher than most other SBP measures. In contrast to SBP, all diastolic BP readings yielded similar results.

CONCLUSIONS

Cardiovascular risk prediction is improved by successive office SBP values, especially when the first reading is discarded. These findings reinforce the necessity of using multiple office BP readings.

Variability in Reporting eGFR at Dialysis Initiation in Canada: A Research Letter

Background

Estimated glomerular filtration rate (eGFR) at dialysis initiation is increasingly recognized as a key quality indicator (QI) for patients with end-stage kidney disease (ESKD). Specifically, guidelines recommend assessing deferral of dialysis initiation until symptoms arise or if the eGFR is ≤6 mL/min/1.73 m2. Despite the recognition of the importance of this QI, how eGFR at the time of dialysis initiation is defined, collected, and tracked at dialysis centers across Canada remains unknown.

Objectives

To identify how provincial renal programs define eGFR at dialysis initiation, to compare practice across Canadian provinces, and to determine if there is a consistent benchmark for deferred dialysis start.

Design

Cross-sectional survey distributed to the medical leads of each provincial renal program, administered from July 2021 to November 2021. Quebec was not included given it did not yet participate in Canadian Organ Replacement Register (CORR) data submission.

Setting

The survey was designed and distributed by the Canadian Society of Nephrology Quality Improvement & Implementation Science Committee (CSN-QUIS) Indicator Working Group.

Methods

The survey asked respondents on how eGFR is defined, collected, reported, and perceived barriers to QI data collection. The National Senior Renal Leaders Forum helped identify the key provincial medical leads to disseminate the survey for completion.

Results

Surveys were distributed to the medical leads of the 9 provincial renal programs that participate in CORR. In total, there were 8 responses. Five provinces submit eGFR for all new dialysis starts and 3 provinces only submit this information for chronic patients. There is variation in determining when a patient with acute kidney injury requiring dialysis is classified as a chronic patient. Four provinces use a 30-day trigger, 3 provinces use a 90-day trigger, and the patient's nephrologist makes this determination in 1 province. The creatinine used for the eGFR at dialysis initiation was the value measured on the first dialysis session (ie, day 0) for 5 provinces; the last outpatient clinic creatinine value in 2 provinces, and 1 province did not have a standard definition. Three provinces did not have a benchmark target for eGFR at dialysis initiation, 1 province had a target of <9.5 mL/min/1.73 m2, 3 provinces had a target of <10 mL/min/1.73 m2, 1 province had a target of <15 mL/min/1.73 m2. All 8 responding provincial medical leads support the establishment of a national benchmark for this measure.

Limitations

This survey was restricted to provincial medical leads and therefore is unable to determine practice at individual dialysis sites. The survey was not anonymous, so it may be subject to conformity bias.

Conclusions

There is wide variability in how eGFR at dialysis initiation is measured and reported across Canada. Additionally, there is no consensus on a benchmark target for an intent-to-defer dialysis strategy. Standardization of target eGFR at dialysis initiation may facilitate national reporting and quality improvement initiatives.

Kidney Biopsy Findings Among Allogenic Hematopoietic Stem Cell Transplant Recipients With Kidney Injury: A Case Series

Rationale and Objective

The incidence of kidney disease is high in patients after allogeneic hematopoietic cell transplantation (aHCT). Although rarely performed, kidney biopsy may be useful to make a precise diagnosis because several mechanisms and risk factors can be involved, and to adjust the treatment accordingly. This case series aimed to report the spectrum of biopsy findings from patients with kidney injury after aHCT.

Study Design

Single-center retrospective case series.

Setting and Participants

All individuals who underwent a native kidney biopsy, among all adult patients who received aHCT in a tertiary hospital in Montreal (Canada) from January 1, 2010, to December 31, 2020, were identified, and the clinical data were extracted from their medical records.

Results

A total of 17 patients were included. Indications for biopsy included acute kidney injury (n=6), chronic kidney disease (n=5), nephrotic syndrome (n=4), and subnephrotic proteinuria (n=2). Pathologic findings from the kidney biopsy were heterogenous: 10 patients showed evidence of thrombotic microangiopathy (TMA), 5 of acute tubular injury, and 4 of membranous nephropathy. Cases of acute interstitial nephritis, BK virus nephropathy, immune complex nephropathy, focal and segmental glomerulosclerosis, minimal change disease, and karyomegalic-like interstitial nephritis were also described.

Limitations

There was no systematic kidney biopsy performed for all patients with kidney injury after aHCT. Only a small proportion of patients with kidney damage underwent biopsy, making the results less generalizable.

Conclusions

Kidney biopsy is useful in patients with kidney disease after aHCT to make a precise diagnosis and tailor therapy accordingly. This series is one of the few published studies describing pathologic findings of biopsies performed after aHCT in the context of acute kidney injury and chronic kidney disease. TMA was widely present on biopsy even when there was no clinical suspicion of such a diagnosis, suggesting that the current clinical criteria for a diagnosis of TMA are not sensitive enough for kidney-limited TMA.

CENtral blood pressure Targeting: a pragmatic RAndomized triaL in advanced Chronic Kidney Disease (CENTRAL-CKD): A Clinical Research Protocol

Background

Emerging data favor central blood pressure (BP) over brachial cuff BP to predict cardiovascular and kidney events, as central BP more closely relates to the true aortic BP. Considering that patients with advanced chronic kidney disease (CKD) are at high cardiovascular risk and can have unreliable brachial cuff BP measurements (due to high arterial stiffness), this population could benefit the most from hypertension management using central BP measurements.

Objective

To assess the feasibility and efficacy of targeting central BP as opposed to brachial BP in patients with CKD G4-5.

Design

Pragmatic multicentre double-blinded randomized controlled pilot trial.

Setting

Seven large academic advanced kidney care clinics across Canada.

Patients

A total of 116 adults with CKD G4-5 (estimated glomerular filtration rate [eGFR] < 30 mL/min) and brachial cuff systolic BP between 120 and 160 mm Hg. The key exclusion criteria are 1) ≥ 5 BP drugs, 2) recent acute kidney injury, myocardial infarction, stroke, heart failure or injurious fall, 3) previous kidney replacement therapy.

Methods

Double-blind randomization to a central or a brachial cuff systolic BP target (both < 130 mm Hg) as measured by a validated central BP device. The study duration is 12 months with follow-up visits every 2 to 4 months, based on local practice. All other aspects of CKD management are at the discretion of the attending nephrologist.

Outcomes

Primary Feasibility: Feasibility of a large-scale trial based on predefined components. Primary Efficacy: Carotid-femoral pulse wave velocity at 12 months. Others: Efficacy (eGFR decline, albuminuria, BP drugs, and quality of life); Events (major adverse cardiovascular events, CKD progression, hospitalization, mortality); Safety (low BP events and acute kidney injury).

Limitations

May be challenging to distinguish whether central BP is truly different from brachial BP to the point of significantly influencing treatment decisions. Therapeutic inertia may be a barrier to successfully completing a randomized trial in a population of CKD G4-5. These 2 aspects will be evaluated in the feasibility assessment of the trial.

Conclusion

This is the first trial to evaluate the feasibility and efficacy of using central BP to manage hypertension in advanced CKD, paving the way to a future large-scale trial.

Trial registration

clinicaltrials.gov (NCT05163158).

Single-Bolus Tinzaparin Anticoagulation in Extended Hemodialysis Session: A Feasibility Study

Key Points

A single bolus of tinzaparin is effective for 8-hour hemodialysis session. Eight-hour simulation sessions with anti-Xa monitoring are useful to adjust tinzaparin dose.

Background

Few studies have assessed the use of low-molecular weight heparins for anticoagulation during extended hemodialysis (HD) sessions. This study aimed to evaluate the efficacy of a single bolus of tinzaparin for anticoagulation of the extracorporeal circuit and dialyzer in 8-hour HD sessions.

Methods

This single-center study included all patients who underwent a single 8-hour simulation session as part of their nocturnal home HD training between 2009 and 2020. Tinzaparin was delivered as a single-bolus injection at time 0 with dosing on the basis of doubling of standard 4-hour session dose. Tinzaparin efficacy was examined using visual observations (score 1–4) of the dialyzer and venous bubble trap at the end of dialysis and using anti-Xa measured at 15 and 30 minutes and 1, 2, 4, 6, and 8 hours after HD start.

Results

Forty-seven patients were included. The mean tinzaparin dose was 107±20 IU/kg. Anti-Xa levels peaked at 15 minutes with 1.3±0.4 IU/ml and progressively declined reaching 0.9±0.3 IU/ml at 1 hour, 0.4±0.21 IU/ml at 4 hours, and 0.15±0.15 IU/ml at 8 hours. After the 8-hour session, none of the patients had severe clotting of their dialyzer or venous chamber. Moderate blood clotting was observed in the dialyzer of 6 patients (20%) and in the venous chamber of 22 patients (61%). On the basis of the simulation results, tinzaparin dose was increased in 27 patients (58%) with a mean home-discharge dose of 123±28 IU/kg.

Conclusions

This study shows that anti-Xa levels stabilized rapidly after administration of tinzaparin for 8-hour HD. Administration of a single-bolus tinzaparin at the start of an 8-hour dialysis session seemed effective, although dose adjustment may be required.

A third SARS-CoV-2 mRNA vaccine dose in people receiving hemodialysis overcomes B cell defects but elicits a skewed CD4+ T cell profile

Cellular immune defects associated with suboptimal responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mRNA vaccination in people receiving hemodialysis (HD) are poorly understood. We longitudinally analyze antibody, B cell, CD4⁺, and CD8⁺ T cell vaccine responses in 27 HD patients and 26 low-risk control individuals (CIs). The first two doses elicit weaker B cell and CD8⁺ T cell responses in HD than in CI, while CD4⁺ T cell responses are quantitatively similar. In HD, a third dose robustly boosts B cell responses, leads to convergent CD8⁺ T cell responses, and enhances comparatively more T helper (T_H) immunity. Unsupervised clustering of single-cell features reveals phenotypic and functional shifts over time and between cohorts. The third dose attenuates some features of T_H cells in HD (tumor necrosis factor alpha [TNFα]/interleukin [IL]-2 skewing), while others (CCR6, CXCR6, programmed cell death protein 1 [PD-1], and HLA-DR overexpression) persist. Therefore, a third vaccine dose is critical to achieving robust multifaceted immunity in hemodialysis patients, although some distinct T_H characteristics endure.

Lived Experiences of Hemodialysis Health Care Workers during the COVID-19 Pandemic: A Qualitative Study from the Quebec Renal Network

Key Points

Hemodialysis workers' well-being and work were affected by the COVID-19 pandemics. Effective communication strategies and taking into account psychological distress are ways to mitigate the challenges faced by health care workers.

Background

The COVID-19 pandemic has disrupted health systems and created numerous challenges in hospitals worldwide for patients and health care workers (HCWs). Hemodialysis centers are at risk of COVID-19 outbreaks given the difficulty of maintaining social distancing and the fact that hemodialysis patients are at higher risk of being infected with COVID-19. During the COVID-19 pandemic, HCWs have had to face many challenges and stressors. Our study was designed to gain HCWs' perspectives on their experiences of the impacts of the COVID-19 pandemic in hemodialysis units.

Methods

Semistructured interviews were conducted with 22 HCWs (nurses, nephrologists, pharmacists, social workers, patient attendants, and security agents) working in five hemodialysis centers in Montreal, between November 2020 and May 2021. The content of the interviews was analyzed using thematic analysis.

Results

Four themes were identified during the interviews. The first was the impact of COVID-19 on work organization, regarding which participants reported an increased workload, a need for a consistent information strategy, and positive innovations such as telemedicine. The second theme was challenges associated with communicating and caring for dialysis patients during the pandemic. The third theme was psychological distress experienced by hemodialysis staff and the psychosocial impact of COVID-19 on their personal lives. The fourth theme was recommendations made by participants for future public health emergencies, such as maintaining public health measures, ensuring an adequate supply of protective equipment, and developing a consistent communication strategy.

Conclusions

During the first and second waves of the COVID-19 pandemic, HCWs working in hemodialysis units faced multiple challenges that affected their well-being and their work. To minimize challenges for HCWs in hemodialysis during a future pandemic, the health care system should provide an adequate supply of protective equipment, develop effective communication strategies, and take into account the psychological distress related to HCWs' professional and personal lives.

Cardiovascular Effects of Home Dialysis Therapies: A Scientific Statement From the American Heart Association

Cardiovascular disease is the leading cause of morbidity and mortality in patients with end-stage kidney disease. Currently, thrice-weekly in-center hemodialysis for 3 to 5 hours per session is the most common therapy worldwide for patients with treated kidney failure. Outcomes with thrice-weekly in-center hemodialysis are poor. Emerging evidence supports the overarching hypothesis that a more physiological approach to administering dialysis therapy, including in the home through home hemodialysis or peritoneal dialysis, may lead to improvement in several cardiovascular risk factors and cardiovascular outcomes compared with thrice-weekly in-center hemodialysis. The Advancing American Kidney Health Initiative, which has a goal of increasing the use of home dialysis, is aligned with the American Heart Association's 2024 mission to champion a full and healthy life and health equity. We conclude that incorporation of interdisciplinary care models to increase the use of home dialysis therapies in an equitable manner will contribute to the ultimate goal of improving outcomes for patients with kidney failure and cardiovascular disease.

Prediction of Cardiovascular Events by Pulse Waveform Parameters: Analysis of CARTaGENE

Background Waveform parameters provide approximate data about aortic wave reflection. However, their association with cardiovascular events remains controversial and their role in cardiovascular prediction is unknown. Methods and Results We analyzed participants aged between 40 and 69 from the population-based CARTaGENE cohort. Baseline pulse wave analysis (central pulse pressure, augmentation index) and wave separation analysis (forward pressure, backward pressure, reflection magnitude) parameters were derived from radial artery tonometry. Associations between each parameter and major adverse atherosclerotic events (MACE; cardiovascular death, stroke, myocardial infarction) were obtained using adjusted Cox models. The incremental predictive value of each parameter compared with the 10-year atherosclerotic cardiovascular disease score alone was assessed using hazard ratios, c-index differences, continuous net reclassification indexes, and integrated discrimination indexes. From 17 561 eligible patients, 2315 patients had a MACE during a median follow-up of 10.1 years. Central pulse pressure, forward pressure, and backward pressure, but not augmentation index and reflection magnitude, were significantly associated with MACE after full adjustment. All parameters except forward pressure statistically improved MACE prediction compared with the atherosclerotic cardiovascular disease score alone. The greatest prediction improvement was seen with augmentation index and reflection magnitude but remained small in magnitude. These 2 parameters enhanced predictive performance more strongly in patients with low baseline atherosclerotic cardiovascular disease scores. Up to 5.7% of individuals were reclassified into a different risk stratum by adding waveform parameters to atherosclerotic cardiovascular disease scores. Conclusions Some waveform parameters are independently associated with MACEs in a population-based cohort. Augmentation index and reflection magnitude slightly improve risk prediction, especially in patients at low cardiovascular risk.

Assisted Peritoneal Dialysis Implementation: A Pilot Program From a Large Dialysis Unit in Quebec

Background:

Kidney failure prevalence is increasing in older patients for whom dialysis initiation can be challenging. Assisted peritoneal dialysis (PD), where PD is performed with the help of a healthcare worker, can facilitate PD for frailer patients who may not be candidate otherwise.

Objectives:

This study aimed to assess the feasibility of implementing the first pilot assisted PD program in Quebec (Canada) and to evaluate the characteristics and outcomes of the PD cohort before and after assisted PD availability.

Design:

Observational retrospective cohort study.

Setting and Population:

All adult patients initiating PD between 2015 and 2020 in a single-center dialysis unit were included.

Measurements:

Incidence, characteristics, and outcomes of patients with PD were compared between (1) the “pre” (2015-2017) and the “post” assisted PD era (2018-2020) and (2) patients with assisted PD and independent PD in the more recent period.

Methods:

The primary outcome was peritonitis rate over the first year. Secondary outcomes included hospitalization, transfers to in-center hemodialysis (HD) and mortality.

Results:

Overall, 124 patients initiated PD with an annual incidence of 17 ± 3 patients during the “pre” and 24 ± 8 patients during the “post” assisted PD era (P = .18). First-year peritonitis rate was similar over the 2 eras. Years of PD initiation and use of assisted PD were not associated with risk peritonitis (over total follow-up) after adjustment. Adjusted hazard of transfer to HD or death was higher during the “post” era (hazard ratio [HR]: 2.77; 95% confidence interval [CI]: 1.42-5.58). Seventeen patients received assisted PD including 13 (18%) of the 72 patients initiated between 2018 and 2020. Patients with assisted PD were older than those with independent PD (72 [64-84] vs. 59 [47-67], P = .006) and received assistance for 0.8 (0.4-1.5) years. When comparing assisted and independent cohorts, there were no differences in crude rates of peritonitis or hospitalization.

Limitations:

Single-center study with small sample size.

Conclusion:

This study shows the feasibility of implementing an assisted PD program, with favorable overall outcomes including similar rates of peritonitis during the first year after PD initiation.

Accuracy Difference of Noninvasive Blood Pressure Measurements by Sex and Height

IMPORTANCE

Women are at higher risk of cardiovascular events than men with similar blood pressure (BP). Whether this discrepancy in risk is associated with the accuracy of brachial cuff BP measurements is unknown.

OBJECTIVES

To examine the difference in brachial cuff BP accuracy in men and women compared with invasively measured aortic BP and to evaluate whether noninvasive central BP estimation varies with sex.

DESIGN, SETTING, AND PARTICIPANTS

This cross-sectional study enrolled 500 participants without severe aortic stenosis or atrial fibrillation from January 1 to December 31, 2019, who were undergoing nonurgent coronary angiography at a tertiary care academic hospital.

EXPOSURES

Simultaneous measurements of invasive aortic BP and noninvasive BP.

MAIN OUTCOMES AND MEASURES

Sex differences in accuracy were determined by calculating the mean difference between the noninvasive measurements (brachial and noninvasive central BP) and the invasive aortic BP (reference). Linear regression and mediation analyses were performed to identify mediators between sex and brachial cuff accuracy.

RESULTS

This study included 500 participants (145 female [29%] and 355 male [71%]; 471 [94%] White; mean [SD] age, 66 [10] years). Baseline characteristics were similar for both sexes apart from body habitus. Despite similar brachial cuff systolic BP (SBP) (mean [SD], 124.5 [17.7] mm Hg in women vs 124.4 [16.4] in men; P = .97), invasive aortic SBP was higher in women (mean [SD], 130.9 [21.7] in women vs 124.7 [20.1] mm Hg in men; P < .001). The brachial cuff was relatively accurate compared with invasive aortic SBP estimation in men (mean [SD] difference, -0.3 [11.7] mm Hg) but not in women (mean [SD] difference, -6.5 [12.1] mm Hg). Noninvasive central SBP (calibrated for mean and diastolic BP) was more accurate in women (mean [SD] difference, 0.6 [15.3] mm Hg) than in men (mean [SD] difference, 8.3 [14.2] mm Hg). This association of sex with accuracy was mostly mediated by height (3.4 mm Hg; 95% CI, 1.1-5.6 mm Hg; 55% mediation).

CONCLUSIONS AND RELEVANCE

In this cross-sectional study, women had higher true aortic SBP than men with similar brachial cuff SBP, an association that was mostly mediated by a shorter stature. This difference in BP measurement may lead to unrecognized undertreatment of women and could partly explain why women are at greater risk for cardiovascular diseases for a given brachial cuff BP than men. These findings may justify the need to study sex-specific BP targets or integration of sex-specific parameters in BP estimation algorithms.

Lived Experiences of Patients Receiving Hemodialysis during the COVID-19 Pandemic: A Qualitative Study from the Quebec Renal Network

Background

Hemodialysis patients have faced unique challenges during the COVID-19 pandemic. They face high risk of death if infected and have unavoidable exposure to others when they come to hospital three times weekly for their life-saving treatments. The objective of this study was to gain a better understanding of the scope and magnitude of the effects of the pandemic on the lived experience of patients receiving in-center hemodialysis.

Methods

We conducted semi-structured interviews with 22 patients who were undergoing dialysis treatments in five hemodialysis centers in Montreal from November 2020 to May 2021. Interviews were transcribed and then analyzed using thematic content analysis.

Results

Most participants reported no negative effects of the COVID-19 pandemic on their hemodialysis care. Several patients had negative feelings related to forced changes in their dialysis schedules, and this was especially pronounced for indigenous patients in a shared living situation. Some patients were concerned about contracting COVID-19, especially during public transportation, whereas others expressed confidence that the physical distancing and screening measures implemented at the hospital would protect them and their loved ones. Some participants reported that masks negatively affected their interactions with health care workers, and for many others, the pandemic was associated with feelings of loneliness. Finally, some respondents reported some positive effects of the pandemic, including use of telemedicine and creating a sense of solidarity.

Conclusions

Patients undergoing hemodialysis reported no negative effects on their medical care but faced significant disruptions in their routines and social interactions due to the COVID-19 pandemic. Nevertheless, they showed great resilience in their ability to adapt to the new reality of their hemodialysis treatments. We also show that studies focused on understanding the lived experiences of indigenous patients and patients from different ethnic backgrounds are needed in order reduce inequities in care during public health emergencies.

Accessing hemodialysis clinics during the COVID-19 pandemic

Transportation is a key element of access to healthcare. The COVID-19 pandemic posed unique and unforeseen challenges to patients receiving hemodialysis who rely on three times weekly transportation to receive their life-saving treatments, but there is little data on the problems they faced. This study explores the attitudes, fears, and concerns of hemodialysis patients during the pandemic with a focus on their travel to/from dialysis treatments. A mixed methods travel survey was distributed to hemodialysis patients from three urban centers in Montréal, Canada, during the pandemic (n = 43). The survey included closed questions that were analysed through descriptive statistics as well as open-ended questions that were assessed through thematic analysis. Descriptive statistics show that hemodialysis patients are more fearful of contracting COVID-19 in transit than they are at the treatment center. Patients taking paratransit, public transportation, and taxis are more fearful of COVID-19 while traveling than those who drive, who are driven, or who walk to the clinic. In the open-ended questions, patients reported struggling with confusing COVID-19 protocols in public transport, including conflicting information on whether paratransit taxis allowed one or multiple passengers. Paratransit was the most used travel mode to access treatment (n = 30), with problems identified in the open-ended questions, such as long and unreliable pickup windows, and extended travel times. To limit COVID-19 exposure and stress for paratransit users, agencies should consider sitting one patient per paratransit taxi, clearly communicating COVID-19 protocols online and in the vehicles, and tracking vehicles for more efficient pickups.

Mortality Trends after Transfer from Peritoneal Dialysis to Hemodialysis

Introduction

Transition to hemodialysis (HD) is a common outcome in peritoneal dialysis (PD), but the associated mortality risk is poorly understood. This study sought to identify rates of and risk factors for mortality after transitioning from PD to HD.

Methods

Patients with incident PD (between 2000 and 2014) who transferred to HD for ≥1 day were identified, using data from Australia and New Zealand Dialysis and Transplantation registry (ANZDATA), Canadian Organ Replacement Register (CORR), Europe Renal Association (ERA) Registry, and the United States Renal Dialysis System (USRDS). Crude mortality rates were calculated for the first 180 days after transfer. Separate multivariable Cox models were built for early (<90 days), medium (90–180 days), and late (>180 days) periods after transfer.

Results

Overall, 6683, 5847, 21,574, and 80,459 patients were included from ANZDATA, CORR, ERA Registry, and USRDS, respectively. In all registries, crude mortality rate was highest during the first 30 days after a transfer to HD declining thereafter to nadir at 4 to 6 months. Crude mortality rates were lower for patients transferring in the most recent years (than earlier). Older age, PD initiation in earlier cohorts, and longer PD vintage were associated with increased risk of death, with the strongest associations during the first 90 days after transfer and attenuating thereafter. Mortality risk was lower for men than women <90 days after transfer, but higher after 180 days.

Conclusion

In this multinational study, mortality was highest in the first month after a transfer from PD to HD and risk factors varied by time period after transfer. This study highlights the vulnerability of patients at the time of modality transfer and the need to improve transitions.

Qualitative and Quantitative Dosage of the Anti M-Type Phospholipase A2 Receptor Autoantibody: One-Year Experience in Quebec's Reference Center

Background:

Quantification of the M-type phospholipase A2 receptor antibodies (anti-PLA2R) is now an essential tool for diagnosis and management of primary membranous nephropathy (MN). Since October 2018, Hôpital Maisonneuve-Rosemont (HMR) has been designated as Quebec’s reference center for serum anti-PLA2R antibody testing by the Institut National d’Excellence en Santé et Services Sociaux (INESSS), the regulatory body on drugs and tests usage in Quebec.

Objectives:

To describe the 2-step method of serum qualitative and quantitative anti-PLA2R antibody testing during its first year of use in Quebec and analyze its diagnostic value in the province’s population.

Design:

Retrospective cohort study.

Setting:

Single-center academic teaching hospital in Quebec, Canada.

Patients:

All patients who had a serum anti-PLA2R antibody test analyzed at HMR from October 1, 2018, to October 1, 2019, were included in the study.

Measurements:

Serum anti-PLA2R antibodies were screened by indirect immunofluorescence tests. If results were positive or undetermined, it was followed by a quantitative enzyme-linked immunosorbent assay (ELISA) test. Both tests were based on a commercial kit developed by the same company.

Methods:

We calculated sensitivity, specificity, predictive value, and likelihood ratio for both tests, using kidney biopsy findings performed at HMR as the gold standard.

Results:

In Quebec, a total of 1690 tests were performed among 1025 patients during the study year. A small proportion of these patients (8%) were followed at HMR. Patients tested at HMR and in the rest of Quebec had similar characteristics. Test validity was only characterized for patients tested at HMR. Sensitivity and specificity were, respectively, 58% and 100% for the qualitative test, and 71% and 100% for the quantitative test. The combined net sensitivity was 42% and the net specificity 100%. The net positive and negative predictive value were 100% and 84% respectively, whereas the net negative likelihood ratio was 0.58.

Limitations:

As the detailed analysis was only possible in the small proportion of patients clinically followed at HMR, there is a possible selection bias. Another potential selection bias was the focus on patients who were selected to have a kidney biopsy, probably because of more severe disease, higher probability of glomerulonephritis, or lesser number of comorbidities. Given the retrospective nature of this study, there was no systematic kidney biopsy or serum PLA2R antibody testing performed. Finally, we were unable to provide detailed information on the timing between immunosuppressive therapy and anti-PLA2R results.

Conclusions:

Serum anti-PLA2R antibody testing was widely used in Quebec during its first year of availability. A 2-step approach, using a qualitative test first, followed by a quantitative test if the results are positive or undetermined, appears efficient to avoid useless quantitative testing in negative patients and to better characterize undetermined results on immunofluorescence.

Trial registration:

Due to the retrospective nature of this study, no trial registration was performed.

Home versus In-Center Dialysis and Day of the Week Hospitalization: A Cohort Study

Background

The dialysis treatment day after the 2-day interdialytic interval (Monday/Tuesday) is associated with a heightened risk of hospitalization for patients on in-center hemodialysis (ICHD). In this national cohort study, we sought to characterize hospitalizations by day of the week for patients receiving ICHD, home HD (HHD), and peritoneal dialysis (PD) and to identify whether there were differences in the probability of a Monday/Tuesday admission for each modality type.

Methods

Patients on maintenance dialysis in Canada were analyzed from 2005 to 2014 using the Canadian Organ Replacement Register. Patients on hemodialysis were categorized as those receiving ICHD, HHD, frequent ICHD, or frequent HHD (the latter two included short daily and nocturnal HD). Hospitalizations were attributed to the previous treatment if they occurred within 30 days of a treatment change. Differences in the proportion of patients experiencing a Monday/Tuesday admission with all other days of the week were compared using a generalized linear model with binomial distribution and reported using adjusted odds ratios (OR) with 95% CIs.

Results

Overall, 27,430 individuals experienced 111,748 hospitalization episodes. Rates per 1000 patient days were 3.76, 2.98, 2.71, 2.16, and 2.13 for each of frequent ICHD, ICHD, PD, HHD, and frequent HHD, respectively. Compared with those on ICHD, only patients receiving frequent HHD (OR, 0.89; 95% CI, 0.81 to 0.97) and PD (OR, 0.95; 95% CI, 0.93 to 0.97) had a lower odds of experiencing a Monday/Tuesday admission. The OR was lower when restricted to hospitalization episodes for cardiovascular reasons comparing frequent HHD with ICHD (OR, 0.68; 95% CI, 0.48 to 0.96).

Conclusion

In this nationally representative cohort, we identified that the probability of a Monday/Tuesday admission was lower for frequent HHD and PD compared with ICHD, most notably for hospitalizations due to cardiovascular causes. Gaining a better understanding of the reasons behind this observation may help to develop future strategies to reduce overall and cause-specific hospitalization for patients receiving dialysis.

Infection control measures to prevent outbreaks of COVID-19 in Quebec hemodialysis units: a cross-sectional survey

BACKGROUND

Limited space and resources are potential obstacles to infection prevention and control (IPAC) measures in in-centre hemodialysis units. We aimed to assess IPAC measures implemented in Quebec's hemodialysis units during the spring of 2020, describe the characteristics of these units and document the cumulative infection rates during the first year of the COVID-19 pandemic.

METHODS

For this cross-sectional survey, we invited leaders from 54 hemodialysis units in Quebec to report information on the physical characteristics of the unit and their perceptions of crowdedness, which IPAC measures were implemented from Mar. 1 to June 30, 2020, and adherence to and feasibility of appropriate IPAC measures. Participating units were contacted again in March 2021 to collect information on the number of COVID-19 cases in order to derive the cumulative infection rate of each unit.

RESULTS

Data were obtained from 38 of the 54 units contacted (70% response rate), which provided care to 4485 patients at the time of survey completion. Fourteen units (37%) had implemented appropriate IPAC measures by 3 weeks after Mar. 1, and all 38 units had implemented them by 6 weeks after. One-third of units were perceived as crowded. General measures, masks and screening questionnaires were used in more than 80% of units, and various distancing measures in 55%-71%; reduction in dialysis frequency was rare. Data on cumulative infection rates were obtained from 27 units providing care to 4227 patients. The cumulative infection rate varied from 0% to 50% (median 11.3%, interquartile range 5.2%-20.2%) and was higher than the reported cumulative infection rate in the corresponding region in 23 (85%) of the 27 units.

INTERPRETATION

Rates of COVID-19 infection among hemodialysis recipients in Quebec were elevated compared to the general population during the first year of the pandemic, and although hemodialysis units throughout the province implemented appropriate IPAC measures rapidly in the spring of 2020, many units were crowded and could not maintain physical distancing. Future hemodialysis units should be designed to minimize airborne and droplet transmission of infection.

Multicenter registry analysis comparing survival on home hemodialysis and kidney transplant recipients in Australia and New Zealand

BACKGROUND

In the era of organ shortage, home hemodialysis (HHD) has been identified as the possible preferential bridge to kidney transplantation. Data are conflicting regarding the comparability of HHD and transplantation outcomes. This study aimed to compare patient and treatment survival between HHD patients and kidney transplant recipients.

METHODS

The Australia and New Zealand Dialysis and Transplant Registry was used to include incident HHD patients on Day 90 after initiation of kidney replacement therapy and first kidney-only transplant recipients in Australia and New Zealand from 1997 to 2017. Survival times were analyzed using the Kaplan-Meier product-limit method comparing HHD patients with subtypes of kidney transplant recipients using the log-rank test. Adjusted analyses were performed with multivariable Cox proportional hazards regression models for time to all-cause mortality. Time-to-treatment failure or death was assessed as a composite secondary outcome.

RESULTS

The study compared 1411 HHD patients with 4960 living donor (LD) recipients, 6019 standard criteria donor (SCD) recipients and 2427 expanded criteria donor (ECD) recipients. While LD and SCD recipients had reduced risks of mortality compared with HHD patients [LD adjusted hazard ratio (HR) = 0.57, 95% confidence interval (CI) 0.46-0.71; SCD HR = 0.65 95% CI 0.52-0.79], the risk of mortality was comparable between ECD recipients and HHD patients (HR = 0.90, 95% CI 0.73-1.12). LD, SCD and ECD kidney recipients each experienced superior time-to-treatment failure or death compared with HHD patients.

CONCLUSIONS

This large registry study showed that kidney transplant offers a survival benefit compared with HHD but that this advantage is not significant for ECD recipients.

Risk of hospitalization, technique failure, and death with increased training duration in 3-days-a-week home hemodialysis

INTRODUCTION

Quality training is a core component of successful home hemodialysis (HHD) and training duration varies significantly between dialysis centers as well as at the patient level. This study aimed to assess the adverse outcomes associated with HHD training duration.

METHODS

All HHD patients successfully trained in a single dialysis center between January 2005 and July 2017 were included. A multivariable multiple-events (Andersen-Gill) survival model was built to evaluate the association between training time and main adverse events, including hospitalizations, technique failure, and death on HHD. Potential confounding factors were defined a priori (age, diabetes, coronary artery disease, and year of training start). Adjusted risk of vascular interventions (arteriovenous fistula angioplasties and central venous catheter replacements) was assessed as the secondary outcome in a negative binomial regression.

FINDINGS

Forty-eight patients were included in the study. Median HHD training duration was 86 (67-108) days, using a thrice weekly training schedule. Over a follow-up median time of 2.0 (0.7-3.3) years, three patients died while on HHD, 10 had a definitive transfer to HD, and 18 experienced a least 1 hospitalization (38 hospitalizations in total). Training duration was associated with a higher risk of hospitalization, technique failure, and death in unadjusted (hazard ratio [HR] 1.16 per month, 95% confidence interval [CI] 1.08-1.24) and adjusted multiple events model (HR 1.21, 95% CI 1.04-1.43). Risk of vascular access intervention was also significantly higher with increased training time (adjusted incidence rate ratio 1.31, 95% CI 1.03-1.64, per training month).

DISCUSSION

In this single-center observational study, HHD training duration was associated with a higher risk of adverse events including, death, technique failure, hospitalizations, and vascular access intervention. Enhanced clinical follow-up and home support should be offered to these more vulnerable patients to mitigate this heightened risk.

Short-term antibody response after 1 dose of BNT162b2 vaccine in patients receiving hemodialysis

BACKGROUND:

Patients receiving in-centre hemodialysis are at high risk of exposure to SARS-CoV-2 and death if infected. One dose of the BNT162b2 SARS-CoV-2 vaccine is efficacious in the general population, but responses in patients receiving hemodialysis are uncertain.

METHODS:

We obtained serial plasma from patients receiving hemodialysis and health care worker controls before and after vaccination with 1 dose of the BNT162b2 mRNA vaccine, as well as convalescent plasma from patients receiving hemodialysis who survived COVID-19. We measured anti–receptor binding domain (RBD) immunoglobulin G (IgG) levels and stratified groups by evidence of previous SARS-CoV-2 infection.

RESULTS:

Our study included 154 patients receiving hemodialysis (135 without and 19 with previous SARS-CoV-2 infection), 40 controls (20 without and 20 with previous SARS-CoV-2 infection) and convalescent plasma from 16 patients. Among those without previous SARS-CoV-2 infection, anti-RBD IgG was undetectable at 4 weeks in 75 of 131 (57%, 95% confidence interval [CI] 47% to 65%) patients receiving hemodialysis, compared with 1 of 20 (5%, 95% CI 1% to 23%) controls (p < 0.001). No patient with nondetectable levels at 4 weeks developed anti-RBD IgG by 8 weeks. Results were similar in non-immunosuppressed and younger individuals. Three patients receiving hemodialysis developed severe COVID-19 after vaccination. Among those with previous SARS-CoV-2 infection, median anti-RBD IgG levels at 8 weeks in patients receiving hemodialysis were similar to controls at 3 weeks (p = 0.3) and to convalescent plasma (p = 0.8).

INTERPRETATION:

A single dose of BNT162b2 vaccine failed to elicit a humoral immune response in most patients receiving hemodialysis without previous SARS-CoV-2 infection, even after prolonged observation. In those with previous SARS-CoV-2 infection, the antibody response was delayed. We advise that patients receiving hemodialysis be prioritized for a second BNT162b2 dose at the recommended 3-week interval.

Outcome measures for technique survival reported in peritoneal dialysis: A systematic review

BACKGROUND

Peritoneal dialysis (PD) technique survival is an important outcome for patients, caregivers and health professionals, however, the definition and measures used for technique survival vary. We aimed to assess the scope and consistency of definitions and measures used for technique survival in studies of patients receiving PD.

METHOD

MEDLINE, EMBASE and CENTRAL databases were searched for randomised controlled studies (RCTs) conducted in patients receiving PD reporting technique survival as an outcome between database inception and December 2019. The definition and measures used were extracted and independently assessed by two reviewers.

RESULTS

We included 25 RCTs with a total of 3645 participants (41-371 per trial) and follow up ranging from 6 weeks to 4 years. Terminology used included 'technique survival' (10 studies), 'transfer to haemodialysis (HD)' (8 studies) and 'technique failure' (7 studies) with 17 different definitions. In seven studies, it was unclear whether the definition included transfer to HD, death or transplantation and eight studies reported 'transfer to HD' without further definition regarding duration or other events. Of those remaining, five studies included death in their definition of a technique event, whereas death was censored in the other five. The duration of HD necessary to qualify as an event was reported in only four (16%) studies. Of the 14 studies reporting causes of an event, all used a different list of causes.

CONCLUSION

There is substantial heterogeneity in how PD technique survival is defined and measured, likely contributing to considerable variability in reported rates. Standardised measures for reporting technique survival in PD studies are required to improve comparability.

Survival comparisons in home hemodialysis: Understanding the present and looking to the future

A number of studies have compared relative survival for home hemodialysis patients (including longer hours/more frequent schedules) and other forms of renal replacement therapy. While informative, many of these studies have been limited by issues pertaining to their observational design including selection bias and residual confounding. Furthermore the few randomized controlled trials that have been conducted have been underpowered to detect a survival difference. Finally, in the face of a growing recognition of the value of patient-important outcomes beyond survival, the focus of comparisons between dialysis modalities may be changing. In this review, we will discuss the determinants of survival for patients receiving home hemodialysis and address the various studies that have compared relative survival for differing home hemodialysis schedules to each of in-center hemodialysis, peritoneal dialysis and transplantation. We will conclude this review by discussing whether there is an ongoing role for survival analyses in home hemodialysis.

Physical Infrastructure and Integrated Governance Structure for Home Hemodialysis

In view of the growing enthusiasm for home dialysis use, new dialysis centers may build or expend their home hemodialysis program in the next few years. This review will discuss the main challenges faced by small and large home hemodialysis programs in terms of physical spaces, human resource, training considerations, and overall governance. We will elaborate on the inclusion of home hemodialysis in the kidney replacement therapy care continuum, with a specific interest for collaboration and transition between peritoneal dialysis and home hemodialysis programs.

Sodium-glucose cotransporter protein-2 (SGLT-2) inhibitors and glucagon-like peptide-1 (GLP-1) receptor agonists for type 2 diabetes: systematic review and network meta-analysis of randomised controlled trials

OBJECTIVE

To evaluate sodium-glucose cotransporter-2 (SGLT-2) inhibitors and glucagon-like peptide-1 (GLP-1) receptor agonists in patients with type 2 diabetes at varying cardiovascular and renal risk.

DESIGN

Network meta-analysis.

DATA SOURCES

Medline, Embase, and Cochrane CENTRAL up to 11 August 2020.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Randomised controlled trials comparing SGLT-2 inhibitors or GLP-1 receptor agonists with placebo, standard care, or other glucose lowering treatment in adults with type 2 diabetes with follow up of 24 weeks or longer. Studies were screened independently by two reviewers for eligibility, extracted data, and assessed risk of bias.

MAIN OUTCOME MEASURES

Frequentist random effects network meta-analysis was carried out and GRADE (grading of recommendations assessment, development, and evaluation) used to assess evidence certainty. Results included estimated absolute effects of treatment per 1000 patients treated for five years for patients at very low risk (no cardiovascular risk factors), low risk (three or more cardiovascular risk factors), moderate risk (cardiovascular disease), high risk (chronic kidney disease), and very high risk (cardiovascular disease and kidney disease). A guideline panel provided oversight of the systematic review.

RESULTS

764 trials including 421 346 patients proved eligible. All results refer to the addition of SGLT-2 inhibitors and GLP-1 receptor agonists to existing diabetes treatment. Both classes of drugs lowered all cause mortality, cardiovascular mortality, non-fatal myocardial infarction, and kidney failure (high certainty evidence). Notable differences were found between the two agents: SGLT-2 inhibitors reduced admission to hospital for heart failure more than GLP-1 receptor agonists, and GLP-1 receptor agonists reduced non-fatal stroke more than SGLT-2 inhibitors (which appeared to have no effect). SGLT-2 inhibitors caused genital infection (high certainty), whereas GLP-1 receptor agonists might cause severe gastrointestinal events (low certainty). Low certainty evidence suggested that SGLT-2 inhibitors and GLP-1 receptor agonists might lower body weight. Little or no evidence was found for the effect of SGLT-2 inhibitors or GLP-1 receptor agonists on limb amputation, blindness, eye disease, neuropathic pain, or health related quality of life. The absolute benefits of these drugs vary substantially across patients from low to very high risk of cardiovascular and renal outcomes (eg, SGLT-2 inhibitors resulted in 3 to 40 fewer deaths in 1000 patients over five years; see interactive decision support tool (https://magicevidence.org/match-it/200820dist/#!/) for all outcomes.

CONCLUSIONS

In patients with type 2 diabetes, SGLT-2 inhibitors and GLP-1 receptor agonists reduced cardiovascular and renal outcomes, with some differences in benefits and harms. Absolute benefits are determined by individual risk profiles of patients, with clear implications for clinical practice, as reflected in the BMJ Rapid Recommendations directly informed by this systematic review.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42019153180.

The DIalysis Symptom COntrol-Restless Legs Syndrome (DISCO-RLS) Trial: A Protocol for a Randomized, Crossover, Placebo-Controlled Blinded Trial

Background

Restless legs syndrome (RLS) affects approximately 30% of patients with end-stage kidney disease and is associated with impaired sleep and health-related quality of life. Medications used to treat RLS in patients receiving dialysis may have an increased risk of adverse events with dose titration, and residual RLS symptoms are common despite the use of effective treatments. Randomized controlled trials of monotherapy and combination pharmacologic therapy for RLS in hemodialysis are needed.

Objective

To perform a randomized, crossover, placebo-controlled blinded trial of pharmacologic therapy for RLS in hemodialysis.

Design/setting

The DIalysis Symptom COntrol-Restless Legs Syndrome (DISCO-RLS) trial is a randomized, crossover, placebo-controlled blinded trial of fixed low-dose pharmacologic therapy in patients receiving hemodialysis in 10 centers across Canada. It uses patient partners in its design, conduct, and reporting.

Participants

Adults receiving thrice-weekly hemodialysis for at least 3 months with RLS of at least mild symptoms defined International Restless Legs Syndrome Study Group Rating Scale (IRLS) of 10 or more will enter a double placebo run-in period to exclude nonadherent participants and those unable to tolerate double placebo. Seventy-two participants who completed the run-in period will be randomized to 1 of 8 treatment sequences based on modeling with 4 treatment periods.

Methods

Each treatment period lasts 4 weeks and consists of ropinirole 0.5 mg daily and gabapentin 100 mg daily, both together or neither with a double dummy placebo control for each treatment. The primary outcome is the difference in change scores of the IRLS between study treatments. Secondary outcomes are the differences in change scores of the Restless Legs Syndrome-6 Scale, patient global impression, 5-level EQ-5D version, and safety outcomes.

Results

This randomized, crossover, placebo-controlled blinded trial will evaluate the efficacy and safety of fixed low-dose combination of ropinirole and gabapentin in patients receiving hemodialysis with RLS.

Limitations

Patients with chronic kidney disease not on dialysis, kidney transplant recipients and those receiving peritoneal dialysis or home hemodialysis are not included. The intervention's long term safety and efficacy including the risk of augmentation is not captured.

Conclusion

This randomized crossover placebo controlled blinded trial will evaluate the efficacy and safety of fixed low-dose combination ropinirole and gabapentin in patients receiving hemodialysis with RLS.

Trial Registration

ClinicalTrials.gov (NCT03806530).

Arteriovenous Fistula Creation and Estimated Glomerular Filtration Rate Decline in Advanced CKD: A Matched Cohort Study

Background

Kidney failure is associated with a high burden of morbidity and mortality. Previous studies have raised the possibility that arteriovenous fistula (AVF) creation may attenuate eGFR decline. This study aimed to compare eGFR decline in predialysis patients with an AVF, matched to patients oriented toward peritoneal dialysis (PD).

Methods

Predialysis patients with an AVF and those oriented toward PD were retrospectively matched using a propensity score. Time zero was defined as the "AVF creation date" for the AVF group and the "date when eGFR was closest to the matched patient's eGFR at AVF creation" for the PD group. Crude and predicted eGFR decline in AVF and PD groups were compared before and after time zero using mixed-effect linear regressions.

Results

In total, 61 pairs were matched. Crude annual eGFR decline before AVF creation/time zero was -4.1 ml/min per m² per year in the AVF group versus -5.3 ml/min per m² per year in the PD group (P=0.75) and after time zero, -2.5 ml/min per m² per year in the AVF group versus -4.5 ml/min per m² per year in the PD group (P=0.02). The predicted annual decline decreased from -5.1 ml/min per m² per year in the AVF group before AVF creation to -2.8 ml/min per m² per year after (P<0.01), whereas there was no difference in the PD group (-5.5 versus -5.1 ml/min per m² per year respectively, P=0.41).

Conclusions

In this matched study, AVF creation was associated with a deceleration of kidney function decline compared with a control PD-oriented group. Prospective studies are needed to assess the potential mechanisms between vascular access creation and eGFR slope attenuation.

Effect of patient- and center-level characteristics on uptake of home dialysis in Australia and New Zealand: a multicenter registry analysis

BACKGROUND

Home-based dialysis therapies, home hemodialysis (HHD) and peritoneal dialysis (PD) are underutilized in many countries and significant variation in the uptake of home dialysis exists across dialysis centers. This study aimed to evaluate the patient- and center-level characteristics associated with uptake of home dialysis.

METHODS

The Australia and New Zealand Dialysis and Transplant (ANZDATA) Registry was used to include incident dialysis patients in Australia and New Zealand from 1997 to 2017. Uptake of home dialysis was defined as any HHD or PD treatment reported to ANZDATA within 6 months of dialysis initiation. Characteristics associated with home dialysis uptake were evaluated using mixed effects logistic regression models with patient- and center-level covariates, era as a fixed effect and dialysis center as a random effect.

RESULTS

Overall, 54 773 patients were included. Uptake of home-based dialysis was reported in 24 399 (45%) patients but varied between 0 and 87% across the 76 centers. Patient-level factors associated with lower uptake included male sex, ethnicity (particularly indigenous peoples), older age, presence of comorbidities, late referral to a nephrology service, remote residence and obesity. Center-level predictors of lower uptake included small center size, smaller proportion of patients with permanent access at dialysis initiation and lower weekly facility hemodialysis hours. The variation in odds of home dialysis uptake across centers increased by 3% after adjusting for the era and patient-level characteristics but decreased by 24% after adjusting for center-level characteristics.

CONCLUSION

Center-specific factors are associated with the variation in uptake of home dialysis across centers in Australia and New Zealand.

Home Hemodialysis and Peritoneal Dialysis Patient and Technique Survival in Canada

INTRODUCTION

As interest for home dialysis is growing, knowledge of comparative clinical outcomes between peritoneal dialysis (PD) and home hemodialysis (HHD) would help to better inform shared decision making with patients and caregivers during modality discussion. This study aimed to assess differences in risk of mortality and technique failure in an incident home dialysis cohort and, specifically, to assess change in this association through eras.

METHODS

All adults patients initiating PD or HHD, in Canada (excluding Quebec), within 365 days after kidney replacement therapy (KRT) initiation between 2000 and 2013 were included (administrative censoring 31 December 2014). Mortality and treatment failure (transfer to another modality for >90 days or death) were assessed in a multivariable Cox proportional hazard model, with prespecified stratification based on the year of KRT initiation.

RESULTS

The study included 959 HHD and 15,469 PD patients. Compared with incident PD, incident HHD was associated with a lower risk of mortality (adjusted hazard ratio [aHR] = 0.64, 95% confidence interval [CI] = 0.53-0.78), and treatment failure (aHR = 0.52, 95% CI = 0.45-0.60). These lower risks of mortality with HHD were more pronounced for older cohorts (2000-2005: aHR = 0.47, 95% CI = 0.31-0.70; 2006-2010: aHR = 0.70, 95% CI = 0.54-0.89) and not significantly different in the most recent era (2011-2013: aHR = 0.86, 95% CI = 0.51-1.47).

CONCLUSION

In Canadian incident KRT patients, HHD was associated with appreciably lower risks of mortality and treatment failure compared to PD, although this association appeared to be attenuated in the most contemporary era.

Use of Desmopressin Prior to Kidney Biopsy in Patients With High Bleeding Risk

INTRODUCTION

To prevent bleeding after native kidney biopsy (NKB), nephrologists often prescribe desmopressin, especially for patients with reduced estimated glomerular filtration rate (eGFR) at risk of uremia-related platelet dysfunction. However, only 1 randomized study has suggested a beneficial effect for desmopressin in patients with eGFR ≥60 ml/min per 1.73 m2. This retrospective cohort study aimed to evaluate desmopressin effect on postbiopsy bleeding in all patients, regardless of eGFR and other comorbidities.

METHODS

In this retrospective cohort study, all adult patients who underwent an NKB from April 1, 2013, to April 30, 2018, in a tertiary hospital were identified. The association between desmopressin use and bleeding complications, including hemoglobin fall, transfusion, hematoma, symptomatic hematoma, urgent radiologic study, and hypotension, was analyzed using multivariable logistic regression models.

RESULTS

A total of 413 native kidney biopsies were studied, 79% of which were performed after receiving desmopressin. Patients receiving desmopressin had worse chronic kidney disease (eGFR 28 vs. 45 ml/min per 1.73 m2; P < 0.001) and were more often hospitalized (48% vs. 32%; P = 0.009). Despite higher bleeding risk, patients using desmopressin had a similar likelihood of symptomatic hematomas (odds ratio [OR], 0.39; 95% confidence interval [CI], 0.13-1.14) and a lower need for urgent radiologic studies (OR, 0.33; 95% CI, 0.11-0.98).

CONCLUSION

Patients at higher risk of bleeding using desmopressin before kidney biopsy had bleeding complications similar to those not using desmopressin. These results highlight potential important clinical and financial benefits of desmopressin use before kidney biopsy.

P1431MULTI-CENTER REGISTRY ANALYSIS COMPARING SURVIVAL ON HOME HEMODIALYSIS AND KIDNEY TRANSPLANT RECIPIENTS IN AUSTRALIA AND NEW ZEALAND

Background and Aims

In the era of organ shortage, home hemodialysis (HHD) has been identified as the possible preferential bridge to kidney transplantation. Data are conflicting regarding the comparability of HHD and transplantation outcomes. This study aimed to compare patient and treatment survival between HHD patients and kidney transplant recipients.

Method

The Australia and New Zealand Dialysis and Transplant (ANZDATA) Registry was used to include incident HHD patients on day 90 after initiation of kidney replacement therapy and first kidney-only transplant recipients in Australia and New Zealand from 1997 to 2017. Survival times were analyzed using the Kaplan-Meier product limit method comparing HHD patients to subtypes of kidney transplant recipients using the log-rank test. Adjusted analyses were performed with multivariable Cox proportional hazards regression models for time to all-cause mortality. Time-to-treatment failure or death was assessed as a composite secondary outcome.

Results

The study compared 1411 HHD patients to 4960 living donor (LD) recipients, 6019 standard criteria donor (SCD) recipients and 2427 expanded criteria donor (ECD) recipients. While LD and SCD recipients had reduced risks of mortality compared to HHD patients (LD adjusted hazard ratio [HR] 0.57, 95%CI 0.46-0.71; SCD HR 0.65 95%CI 0.52-0.79), the risk of mortality was comparable between ECD recipients and HHD patients (HR 0.90, 95%CI 0.73-1.12). LD, SCD and ECD kidney recipients each experienced superior time-to-treatment failure or death compared to HHD patients.

Conclusion

This large registry study showed that kidney transplant offers a survival benefit compared to HHD but that this advantage is not significant for ECD recipients.

Core Outcome Domains for Trials in Autosomal Dominant Polycystic Kidney Disease: An International Delphi Survey

RATIONALE & OBJECTIVE

Outcomes reported in trials involving patients with autosomal dominant polycystic kidney disease (ADPKD) are heterogeneous and rarely include patient-reported outcomes. We aimed to identify critically important consensus-based core outcome domains to be reported in trials in ADPKD.

STUDY DESIGN

An international 2-round online Delphi survey was conducted in English, French, and Korean languages.

SETTING & PARTICIPANTS

Patients/caregivers and health professionals completed a 9-point Likert scale (7-9 indicating critical importance) and a Best-Worst Scale.

ANALYTICAL APPROACH

The absolute and relative importance of outcomes were assessed. Comments were analyzed thematically.

RESULTS

1,014 participants (603 [60%] patients/caregivers, 411 [40%] health professionals) from 56 countries completed round 1, and 713 (70%) completed round 2. The prioritized outcomes were kidney function (importance score, 8.6), end-stage kidney disease (8.6), death (7.9), blood pressure (7.9), kidney cyst size/growth (7.8), and cerebral aneurysm (7.7). Kidney cyst-related pain was the highest rated patient-reported outcome by both stakeholder groups. Seven themes explained the prioritization of outcomes: protecting life and health, directly encountering life-threatening and debilitating consequences, specificity to ADPKD, optimizing and extending quality of life, hidden suffering, destroying self-confidence, and lost opportunities.

LIMITATIONS

Study design precluded involvement from those without access to internet or limited computer literacy.

CONCLUSIONS

Kidney function, end-stage kidney disease, and death were the most important outcomes to patients, caregivers, and health professionals. Kidney cyst-related pain was the highest rated patient-reported outcome. Consistent reporting of these top prioritized outcomes may strengthen the value of trials in ADPKD for decision making.

Association of Glomerular Hyperfiltration and Cardiovascular Risk in Middle-Aged Healthy Individuals

IMPORTANCE

Glomerular hyperfiltration is associated with increased risk of cardiovascular disease in high-risk conditions, but its significance in low-risk individuals is uncertain.

OBJECTIVE

To determine whether glomerular hyperfiltration is associated with increased cardiovascular risk in healthy individuals.

DESIGN, SETTING, AND PARTICIPANTS

This was a prospective population-based cohort study, for which enrollment took place from August 2009 to October 2010, with follow-up available through March 31, 2016. Analysis of the data took place in October 2019. The cohort was composed of 9515 healthy individuals, defined as individuals without hypertension, diabetes, cardiovascular disease, estimated glomerular filtration rate (eGFR) less than 60 mL/min/1.73 m2, or statin and/or aspirin use, identified among 20 004 patients aged 40 to 69 years with health information accessed through the CARTaGENE research platform.

EXPOSURES

Individuals with glomerular hyperfiltration (eGFR >95th percentile after stratification for sex and age) were compared with individuals with normal filtration rate (eGFR 25th-75th percentiles).

MAIN OUTCOMES AND MEASURES

Adverse cardiovascular events were defined as a composite of cardiovascular mortality, myocardial infarction, unstable angina, heart failure, stroke, and transient ischemic attack. Risk of adverse cardiovascular events was assessed using Cox and fractional polynomial regressions and propensity score matching.

RESULTS

From the 20 004 CARTaGENE participants, 9515 healthy participants (4050 [42.6%] male; median [interquartile range] age, 50.4 [45.9-55.6] years) were identified. Among these, 473 had glomerular hyperfiltration (median [interquartile range] eGFR, 112 [107-115] mL/min/1.73 m2) and 4761 had a normal filtration rate (median [interquartile range] eGFR, 92 [87-97] mL/min/1.73 m2). Compared with the normal filtration rate, glomerular hyperfiltration was associated with an increased cardiovascular risk (hazard ratio, 1.88; 95% CI, 1.30-2.74; P = .001). Findings were similar with propensity score matching. The fractional polynomial regression showed that only the highest eGFR percentiles were associated with increased cardiovascular risk. The cardiovascular risk of individuals with glomerular hyperfiltration was similar to that of the 597 participants with an eGFR between 45 and 60 mL/min/1.73 m2 (hazard ratio, 0.90; 95% CI, 0.56-1.42; P = .64).

CONCLUSIONS AND RELEVANCE

These findings suggest that glomerular hyperfiltration is independently associated with increased cardiovascular risk in middle-aged healthy individuals. This risk profile appears to be similar to stage 3a chronic kidney disease.

Impact of Arteriovenous fistula creation on estimated glomerular filtration rate decline in Predialysis patients

BACKGROUND

Arteriovenous fistula (AVF) is the vascular access of choice for patients on hemodialysis. Recent evidence suggests that AVF creation may slow estimated glomerular filtration rate (eGFR) decline. The study objective was to assess the impact of the AVF creation on eGFR decline, after controlling for key confounding factors.

METHODS

This retrospective cohort study included adult patients followed in a single-center predialysis clinic between 1999 and 2016. Patients with a patent AVF were followed up to 2 years pre- and post-AVF creation. Estimated GFR trajectory was reported using linear mixed models adjusted for demographic characteristics, comorbidities and use of renin-angiotensin-aldosterone blockade.

RESULTS

A total of 146 patients were studied with a median age 68.7 (60.5-75.4) years and a median eGFR at time of AVF creation of 12.8 (11.3-13.9) mL/min/1.73m2. The crude annual eGFR decline rates were - 3.60 ± 4.00 mL/min/1.73 m2 pre- and - 2.28 ± 3.56 mL/min/1.73 m2 post-AVF, resulting in a mean difference of 1.28 mL/min/1.73 m2 (95% CI 0.49, 2.07). In a mixed effect linear regression model, monthly eGFR decline was - 0.63 (95% CI -0.81, - 0.46; p <  0.001) mL/min/1.73m2/month. The period after AVF creation was associated with a relatively higher eGFR (β 0.94, 95% CI 0.61-1.26, p <  0.001). There was a significant association between follow-up time and the period pre/post AVF (β 0.19, 95% CI 0.16, 0.22; p <  0.001) such that eGFR decline was more attenuated each month after AVF creation.

CONCLUSIONS

In this cohort, AVF creation was associated with a significant reduction of eGFR decline. Further prospective studies are needed to confirm this association.

Optimization of Dialysis Modality Transitions for Improved Patient Care

Purpose of review:

Initial and subsequent modality decisions are important, impacting both clinical outcomes and quality of life. Transition from chronic kidney disease to dialysis and between dialysis modalities are periods were patients may be especially vulnerable. Reviewing our current knowledge surrounding these critical periods and identifying areas for future research may allow us to develop dialysis strategies beneficial to patients.

Sources of information:

We searched the electronic database PubMed and queried Google Scholar for English peer-reviewed articles using appropriate keywords (non-exhaustive list): dialysis transitions, peritoneal dialysis, home hemodialysis, integrated care pathway, and health-related quality of life. Primary sources were accessed whenever possible.

Methods:

In this narrative review, we aim to expose the controversies surrounding home-dialysis first strategies and examine the evidence underpinning home-dialysis first strategies as well as home-to-home and home-to-in-center transitions.

Key findings:

Diverse factors must be taken into consideration when choosing initial and subsequent dialysis modalities. Given the limitations of available data (and lack of convincing benefit or detriment of one modality over the other), patient-centered considerations may prime over suspected mortality benefits of one modality or another.

Limitations:

Available data stem almost exclusively from retrospective and observational studies, often using large national and international databases, susceptible to bias. Furthermore, this is a narrative review which takes into account the views and opinions of the authors, especially as it pertains to optimal dialysis pathways.

Implications:

Emphasis must be placed on individual patient goals and preferences during modality selection while planning ahead to achieve timely and appropriate transitions limiting discomfort and anxiety for patients. Further research is required to ascertain specific interventions which may be beneficial to patients.

Predictors of Care Gaps in Home Dialysis: The Home Dialysis Virtual Ward Study

BACKGROUND

Home dialysis patients may be at an increased risk of adverse events after transitional states. The home dialysis virtual ward (HDVW) trial was conducted in Canadian dialysis centers and aimed to evaluate potential care gaps and patient satisfaction during the HDVW.

METHODS

The HDVW was a multicenter single-arm trial including peritoneal dialysis and home hemodialysis patients after 4 different events (hospital discharge, medical procedure, antibiotics, completion of training). Telephone-led interviews using a standardized assessment tool were performed over a 2-week period to assess a patient's care and adjust treatment as required. Upon completion, patients were surveyed to evaluate their perceived impact on domains of care using a rating scale; 1 not satisfied to 10 completely satisfied.

RESULTS

The HDVW trial included 193 patients with a median number of potential care gaps/interventions of 1 (0-2) per patient. Patients admitted to the HDVW after hospital discharge were at a higher risk of potential gaps in care (OR 2.16, 95% CI 1.29-3.62), while longer dialysis vintage was -associated with a lower number of gaps/interventions (OR 0.97 per year, 95% CI 0.95-0.98). A total of 105/193 (54%) patients completed satisfaction surveys. Patients were highly satisfied with the HDVW (median rating scale score 8, IQR 2) and felt it had a positive impact (rating scale score ≥7) on their overall health, understanding of treatment and access to a nephrologist.

CONCLUSION

The HDVW was effective at identifying several potential care gaps, and patients were satisfied across several domains of care. This intervention may be valuable in supporting home dialysis patients during care transitions.

Transition Between Different Renal Replacement Modalities: Gaps in Knowledge and Care-The Integrated Research Initiative

Patients with end-stage kidney disease (ESKD) have different options to replace the function of their failing kidneys. The "integrated care" model considers treatment pathways rather than individual renal replacement therapy (RRT) techniques. In such a paradigm, the optimal strategy to plan and enact transitions between the different modalities is very relevant, but so far, only limited data on transitions have been published. Perspectives of patients, caregivers, and health professionals on the process of transitioning are even less well documented. Available literature suggests that poor coordination causes significant morbidity and mortality.This review briefly provides the background, development, and scope of the INTErnational Group Research Assessing Transition Effects in Dialysis (INTEGRATED) initiative. We summarize the literature on the transition between different RRT modalities. Further, we present an international research plan to quantify the epidemiology and to assess the qualitative aspects of transition between different modalities.

A comparison of technique survival in Canadian peritoneal dialysis and home hemodialysis patients

Background

High discontinuation rates remain a challenge for home hemodialysis (HHD) and peritoneal dialysis (PD). We compared technique failure risks among Canadian patients receiving HHD and PD.

Methods

Using the Canadian Organ Replacement Register, we studied adult patients who initiated HHD or PD within 1 year of beginning dialysis between 2000 and 2012, with follow-up until 31 December 2013. Technique failure was defined as a transfer to any alternative modality for a period of ≥60 days. Technique survival between HHD and PD was compared using a Fine and Gray competing risk model. We also examined the time dependence of technique survival, the association of patient characteristics with technique failure and causes of technique failure.

Results

Between 2000 and 2012, 15 314 patients were treated with a home dialysis modality within 1 year of dialysis initiation: 14 461 on PD and 853 on HHD. Crude technique failure rates were highest during the first year of therapy for both home modalities. During the entire period of follow-up, technique failure was lower with HHD compared with PD (adjusted hazard ratio = 0.79; 95% confidence interval 0.69–0.90). However, the relative technique failure risk was not proportional over time and the beneficial association with HHD was only apparent after the first year of dialysis. Comparisons also varied among subgroups and the superior technique survival associated with HHD relative to PD was less pronounced in more recent years and among older patients. Predictors of technique failure also differed between modalities. While obesity, smoking and small facility size were associated with higher technique failure in both PD and HHD, the association with age and gender differed. Furthermore, the majority of discontinuation occurred for medical reasons in PD (38%), while the majority of HHD patients experienced technique failure due to social reasons or inadequate resources (50%).

Conclusions

In this Canadian study of home dialysis patients, HHD was associated with better technique survival compared with PD. However, patterns of technique failure differed significantly among these modalities. Strategies to improve patient retention across all home dialysis modalities are needed.

The Relationship between Body Mass Index and Organism-Specific Peritonitis

Background

Obesity is increasingly prevalent worldwide, and a greater number of patients initiate renal replacement therapy with a high body mass index (BMI). This study aimed to evaluate the association between BMI and organism-specific peritonitis.

Methods

All adult patients who initiated peritoneal dialysis (PD) in Australia between January 2004 and December 2013 were included. Data were accessed through the Australia and New Zealand Dialysis and Transplant (ANZDATA) Registry. The co-primary outcomes of this study were time to first organism-specific peritonitis episode, specifically gram-positive, gram-negative, culture-negative, and fungal. Secondary outcomes were individual rates of organism-specific peritonitis for the same 4 microbiological categories.

Results

There were 7,381 peritonitis episodes among the 8,343 incident PD patients evaluated. After multivariable adjustment, obese patients (BMI 30 – 34.9 kg/m2) had an increased risk of fungal peritonitis (adjusted hazard ratio [HR] 1.69, 95% confidence interval [CI] 1.18 – 2.42), very obese patients (BMI ≥ 35 kg/m2) had a significantly higher risk of gram-positive peritonitis (HR 1.15, 95% CI 1.02 – 1.30), while both obese and very obese patients experienced significantly higher risks of gram-negative peritonitis (HR 1.29, 95% CI 1.11 – 1.50 and HR 1.30, 95% CI 1.08 – 1.57, respectively) compared with patients with normal BMI (20 – 24.9 kg/m2). Obesity and severe obesity were independently associated with increased incidence rate ratios of all forms of organism-specific peritonitis with a non-significant trend for severe obesity and gram-negative peritonitis association.

Conclusion

Among Australian patients, obesity and severe obesity are associated with significantly increased rates of gram-positive, gram-negative, fungal, and culture-negative peritonitis.

Central and Brachial Blood Pressures, Statins, and Low-Density Lipoprotein Cholesterol: A Mediation Analysis

Central blood pressure may be a better predictor of cardiovascular disease than brachial pressure. Although statins reduce brachial pressure, their impact on central pressure remains unknown. Furthermore, whether this effect is mediated through a decrease in low-density lipoprotein cholesterol (LDL-c) is unknown. This study aims to characterize the association of statins and LDL-c with central and brachial blood pressures and to quantify their respective effects. Of the 20 004 CARTaGENE participants, 16 507 had available central blood pressure, LDL-c, and Framingham risk score. Multivariate analyses were used to evaluate the association between central pressure and LDL-c in subjects with or without statins. The impact of LDL-c on the association between statin and pressure parameters was determined through mediation analyses. LDL-c was positively associated with systolic and diastolic central pressure in nonusers (β=0.077 and 0.106; P<0.001) and in participants with statins for primary (β=0.086 and 0.114; P<0.001) and secondary prevention (β=0.120 and 0.194; P<0.003). Statins as primary prevention were associated with lower central systolic, diastolic, and pulse pressures (-3.0, -1.6, and -1.3 mm Hg; P<0.001). Mediation analyses showed that LDL-c reduction contributed to 15% of central systolic and 44% of central diastolic pressure changes associated with statins and attenuated 22% of the effects on central pulse pressure. Similar results were found with brachial pressure components. In conclusion, reduction of LDL-c was associated with only a fraction of the lower blood pressures in statin user and seemed to be mostly associated with improvement of steady (diastolic) pressure, whereas non-LDL-c-mediated pathways were mostly associated with changes in pulsatile pressure components.

Center Effects and Peritoneal Dialysis Peritonitis Outcomes: Analysis of a National Registry

BACKGROUND

Peritonitis is a common cause of technique failure in peritoneal dialysis (PD). Dialysis center-level characteristics may influence PD peritonitis outcomes independent of patient-level characteristics.

STUDY DESIGN

Retrospective cohort study.

SETTING & PARTICIPANTS

Using Australia and New Zealand Dialysis and Transplant Registry (ANZDATA) data, all incident Australian PD patients who had peritonitis from 2004 through 2014 were included.

PREDICTORS

Patient- (including demographic data, causal organisms, and comorbid conditions) and center- (including center size, proportion of patients treated with PD, and summary measures related to type, cause, and outcome of peritonitis episodes) level predictors.

OUTCOMES & MEASUREMENT

The primary outcome was cure of peritonitis with antibiotics. Secondary outcomes were peritonitis-related catheter removal, hemodialysis therapy transfer, peritonitis relapse/recurrence, hospitalization, and mortality. Outcomes were analyzed using multilevel mixed logistic regression.

RESULTS

The study included 9,100 episodes of peritonitis among 4,428 patients across 51 centers. Cure with antibiotics was achieved in 6,285 (69%) peritonitis episodes and varied between 38% and 86% across centers. Centers with higher proportions of dialysis patients treated with PD (>29%) had significantly higher odds of peritonitis cure (adjusted OR, 1.21; 95% CI, 1.04-1.40) and lower odds of catheter removal (OR, 0.78; 95% CI, 0.62-0.97), hemodialysis therapy transfer (OR, 0.78; 95% CI, 0.62-0.97), and peritonitis relapse/recurrence (OR, 0.68; 95% CI, 0.48-0.98). Centers with higher proportions of peritonitis episodes receiving empirical antibiotics covering both Gram-positive and Gram-negative organisms had higher odds of cure with antibiotics (OR, 1.22; 95% CI, 1.06-1.42). Patient-level characteristics associated with higher odds of cure were younger age and less virulent causative organisms (coagulase-negative staphylococci, streptococci, and culture negative). The variation in odds of cure across centers was 9% higher after adjustment for patient-level characteristics, but 66% lower after adjustment for center-level characteristics.

LIMITATIONS

Retrospective study design using registry data.

CONCLUSIONS

These results suggest that center effects contribute substantially to the appreciable variation in PD peritonitis outcomes that exist across PD centers within Australia.

Multicenter Registry Analysis of Center Characteristics Associated with Technique Failure in Patients on Incident Peritoneal Dialysis

BACKGROUND AND OBJECTIVES

Technique failure is a major limitation of peritoneal dialysis. Our study aimed to identify center- and patient-level predictors of peritoneal dialysis technique failure.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

All patients on incident peritoneal dialysis in Australia from 2004 to 2014 were included in the study using data from the Australia and New Zealand Dialysis and Transplant Registry. Center- and patient-level characteristics associated with technique failure were evaluated using Cox shared frailty models. Death-censored technique failure and cause-specific technique failure were analyzed as secondary outcomes.

RESULTS

The study included 9362 patients from 51 centers in Australia. The technique failure rate was 0.35 (95% confidence interval, 0.34 to 0.36) episodes per patient-year, with a sevenfold variation across centers that was mainly associated with center-level characteristics. Technique failure was significantly less likely in centers with larger proportions of patients treated with peritoneal dialysis (>29%; adjusted hazard ratio, 0.83; 95% confidence interval, 0.73 to 0.94) and more likely in smaller centers (<16 new patients per year; adjusted hazard ratio, 1.10; 95% confidence interval, 1.00 to 1.21) and centers with lower proportions of patients achieving target baseline serum phosphate levels (<40%; adjusted hazard ratio, 1.15; 95% confidence interval, 1.03 to 1.29). Similar results were observed for death-censored technique failure, except that center target phosphate achievement was not significantly associated. Technique failure due to infection, social reasons, mechanical causes, or death was variably associated with center size, proportion of patients on peritoneal dialysis, and/or target phosphate achievement, automated peritoneal dialysis exposure, icodextrin use, and antifungal use. The variation of hazards of technique failure across centers was reduced by 28% after adjusting for patient-specific factors and an additional 53% after adding center-specific factors.

CONCLUSIONS

Technique failure varies widely across centers in Australia. A significant proportion of this variation is related to potentially modifiable center characteristics, including peritoneal dialysis center size, proportion of patients on peritoneal dialysis, and proportion of patients on peritoneal dialysis achieving target phosphate level.

Comparison of Clinical Outcomes and Adverse Events Associated With Glucose-Lowering Drugs in Patients With Type 2 Diabetes: A Meta-analysis

IMPORTANCE

Numerous glucose-lowering drugs are used to treat type 2 diabetes.

OBJECTIVE

To estimate the relative efficacy and safety associated with glucose-lowering drugs including insulin.

DATA SOURCES

Cochrane Library Central Register of Controlled Trials, MEDLINE, and EMBASE databases through March 21, 2016.

STUDY SELECTION

Randomized clinical trials of 24 weeks' or longer duration.

DATA EXTRACTION AND SYNTHESIS

Random-effects network meta-analysis.

MAIN OUTCOMES AND MEASURES

The primary outcome was cardiovascular mortality. Secondary outcomes included all-cause mortality, serious adverse events, myocardial infarction, stroke, hemoglobin A1c (HbA1C) level, treatment failure (rescue treatment or lack of efficacy), hypoglycemia, and body weight.

RESULTS

A total of 301 clinical trials (1,417,367 patient-months) were included; 177 trials (56,598 patients) of drugs given as monotherapy; 109 trials (53,030 patients) of drugs added to metformin (dual therapy); and 29 trials (10,598 patients) of drugs added to metformin and sulfonylurea (triple therapy). There were no significant differences in associations between any drug class as monotherapy, dual therapy, or triple therapy with odds of cardiovascular or all-cause mortality. Compared with metformin, sulfonylurea (standardized mean difference [SMD], 0.18 [95% CI, 0.01 to 0.34]), thiazolidinedione (SMD, 0.16 [95% CI, 0.00 to 0.31]), DPP-4 inhibitor (SMD, 0.33 [95% CI, 0.13 to 0.52]), and α-glucosidase inhibitor (SMD, 0.35 [95% CI, 0.12 to 0.58]) monotherapy were associated with higher HbA1C levels. Sulfonylurea (odds ratio [OR], 3.13 [95% CI, 2.39 to 4.12]; risk difference [RD], 10% [95% CI, 7% to 13%]) and basal insulin (OR, 17.9 [95% CI, 1.97 to 162]; RD, 10% [95% CI, 0.08% to 20%]) were associated with greatest odds of hypoglycemia. When added to metformin, drugs were associated with similar HbA1C levels, while SGLT-2 inhibitors offered the lowest odds of hypoglycemia (OR, 0.12 [95% CI, 0.08 to 0.18]; RD, -22% [-27% to -18%]). When added to metformin and sulfonylurea, GLP-1 receptor agonists were associated with the lowest odds of hypoglycemia (OR, 0.60 [95% CI, 0.39 to 0.94]; RD, -10% [95% CI, -18% to -2%]).

CONCLUSIONS AND RELEVANCE

Among adults with type 2 diabetes, there were no significant differences in the associations between any of 9 available classes of glucose-lowering drugs (alone or in combination) and the risk of cardiovascular or all-cause mortality. Metformin was associated with lower or no significant difference in HbA1C levels compared with any other drug classes. All drugs were estimated to be effective when added to metformin. These findings are consistent with American Diabetes Association recommendations for using metformin monotherapy as initial treatment for patients with type 2 diabetes and selection of additional therapies based on patient-specific considerations.

Center-Specific Factors Associated with Peritonitis Risk-A Multi-Center Registry Analysis

♦

BACKGROUND

Previous studies have reported significant variation in peritonitis rates across dialysis centers. Limited evidence is available to explain this variability. The aim of this study was to assess center-level predictors of peritonitis and their relationship with peritonitis rate variations. ♦

METHODS

All incident peritoneal dialysis (PD) patients treated in Australia between October 2003 and December 2013 were included. Data were accessed through the Australia and New Zealand Dialysis and Transplant Registry. The primary outcome was peritonitis rate, evaluated in a mixed effects negative binomial regression model. Peritonitis-free survival was assessed as a secondary outcome in a Cox proportional hazards model. ♦

RESULTS

Overall, 8,711 incident PD patients from 51 dialysis centers were included in the study. Center-level predictors of lower peritonitis rates included smaller center size, high proportion of PD, low peritoneal equilibration test use at PD start, and low proportion of hospitalization for peritonitis. In contrast, a low proportion of automated PD exposure, high icodextrin exposure and low or high use of antifungal prophylaxis at the time of peritonitis were associated with a higher peritonitis rate. Similar results were obtained for peritonitis-free survival. Overall, accounting for center-level characteristics appreciably decreased peritonitis variability among dialysis centers (p = 0.02). ♦

CONCLUSION

This study identified specific center-level characteristics associated with the variation in peritonitis risk. Whether these factors are directly related to peritonitis risk or surrogate markers for other center characteristics is uncertain and should be validated in further studies.