Global variations in funding and use of hemodialysis accesses: an international report using the ISN Global Kidney Health Atlas.

BACKGROUND: There is a lack of contemporary data describing global variations in vascular access for hemodialysis (HD). We used the third iteration of the International Society of Nephrology Global Kidney Health Atlas (ISN-GKHA) to highlight differences in funding and availability of hemodialysis accesses used for initiating HD across world regions. METHODS: Survey questions were directed at understanding the funding modules for obtaining vascular access and types of accesses used to initiate dialysis. An electronic survey was sent to national and regional key stakeholders affiliated with the ISN between June and September 2022. Countries that participated in the survey were categorized based on World Bank Income Classification (low-, lower-middle, upper-middle, and high-income) and by their regional affiliation with the ISN. RESULTS: Data on types of vascular access were available from 160 countries. Respondents from 35 countries (22% of surveyed countries) reported that > 50% of patients started HD with an arteriovenous fistula or graft (AVF or AVG). These rates were higher in Western Europe (n = 14; 64%), North & East Asia (n = 4; 67%), and among high-income countries (n = 24; 38%). The rates of > 50% of patients starting HD with a tunneled dialysis catheter were highest in North America & Caribbean region (n = 7; 58%) and lowest in South Asia and Newly Independent States and Russia (n = 0 in both regions). Respondents from 50% (n = 9) of low-income countries reported that > 75% of patients started HD using a temporary catheter, with the highest rates in Africa (n = 30; 75%) and Latin America (n = 14; 67%). Funding for the creation of vascular access was often through public funding and free at the point of delivery in high-income countries (n = 42; 67% for AVF/AVG, n = 44; 70% for central venous catheters). In low-income countries, private and out of pocket funding was reported as being more common (n = 8; 40% for AVF/AVG, n = 5; 25% for central venous catheters). CONCLUSIONS: High income countries exhibit variation in the use of AVF/AVG and tunneled catheters. In low-income countries, there is a higher use of temporary dialysis catheters and private funding models for access creation.

Health related quality of life during dialysis modality transitions: a qualitative study.

BACKGROUND: Modality transitions represent a period of significant change that can impact health related quality of life (HRQoL). We explored the HRQoL of adults transitioning to new or different dialysis modalities. METHODS: We recruited eligible adults (≥ 18) transitioning to dialysis from pre-dialysis or undertaking a dialysis modality change between July and September 2017. Nineteen participants (9 incident and 10 prevalent dialysis patients) completed the KDQOL-36 survey at time of transition and three months later. Fifteen participants undertook a semi-structured interview at three months. Qualitative data were thematically analyzed. RESULTS: Four themes and five sub-themes were identified: adapting to new circumstances (tackling change, accepting change), adjusting together, trading off, and challenges of chronicity (the impact of dialysis, living with a complex disease, planning with uncertainty). From the first day of dialysis treatment to the third month on a new dialysis therapy, all five HRQoL domains from the KDQOL-36 (symptoms, effects, burden, overall PCS, and overall MCS) improved in our sample (i.e., those who remained on the modality). CONCLUSIONS: Dialysis transitions negatively impact the HRQoL of people with kidney disease in various ways. Future work should focus on how to best support people during this time.

Advancing Exercise Science for Better Health Outcomes Across the Spectrum of Chronic Kidney Disease.

Despite over 30 years of evidence for improvements in physical function, physical fitness, and health-related quality of life with exercise training in individuals with chronic kidney disease, access to dedicated exercise training programs remains outside the realm of standard of care for most kidney care programs. In this review, we explore possible reasons for this by comparing approaches in other chronic diseases where exercise rehabilitation has become the standard of care, identifying enablers and factors that need to be addressed for continued growth in this area, and discussing knowledge gaps for future research. For exercise rehabilitation to be relevant to all stakeholders and become a sustainable component of kidney care, a focus on the effect of exercise on clinically relevant outcomes that are prioritized by individuals living with kidney disease, use of evidence-based implementation strategies for diverse settings and populations, and approaching exercise as a medical therapy are required.

Addressing feasibility challenges to delivering intradialytic exercise interventions: a theory-informed qualitative study.

BACKGROUND: Intradialytic exercise (IDE) may improve physical function and health-related quality of life. However, incorporating IDE into standard hemodialysis care has been slow due to feasibility challenges. We conducted a multicenter qualitative feasibility study to identify potential barriers and enablers to IDE and generate potential solutions to these factors. METHODS: We conducted 43 semistructured interviews with healthcare providers and patients across 12 hospitals in Ontario, Canada. We used the Theoretical Domains Framework and directed content analysis to analyze the data. RESULTS: We identified eight relevant domains (knowledge, skills, beliefs about consequences, beliefs about capabilities, environmental context and resources, goals, social/professional role and identity, and social influences) represented by three overarching categories: knowledge, skills and expectations: lack of staff expertise to oversee exercise, uncertainty regarding exercise risks, benefits and patient interest, lack of knowledge regarding exercise eligibility; human, material and logistical resources: staff concerns regarding workload, perception that exercise professionals should supervise IDE, space, equipment and scheduling conflict concerns; and social dynamics of the unit: local champions and patient stories contribute to IDE sustainability. We developed a list of actionable solutions by mapping barriers and enablers to behavior change techniques. We also developed a feasibility checklist of 47 questions identifying key factors to address prior to IDE launch. CONCLUSIONS: Evidence-based solutions to identified barriers to and enablers of IDE and a feasibility checklist may help recruit and support units, staff and patients and address key challenges to the delivery of IDE in diverse clinical and research settings.

Global Policy Barriers and Enablers to Exercise and Physical Activity in Kidney Care.

OBJECTIVE: Impairment in physical function and physical performance leads to decreased independence and health-related quality of life in people living with chronic kidney disease and end-stage kidney disease. Physical activity and exercise in kidney care are not priorities in policy development. We aimed to identify global policy-related enablers, barriers, and strategies to increase exercise participation and physical activity behavior for people living with kidney disease. DESIGN AND METHODS: Guided by the Behavior Change Wheel theoretical framework, 50 global renal exercise experts developed policy barriers and enablers to exercise program implementation and physical activity promotion in kidney care. The consensus process consisted of developing themes from renal experts from North America, South America, Continental Europe, United Kingdom, Asia, and Oceania. Strategies to address enablers and barriers were identified by the group, and consensus was achieved. RESULTS: We found that policies addressing funding, service provision, legislation, regulations, guidelines, the environment, communication, and marketing are required to support people with kidney disease to be physically active, participate in exercise, and improve health-related quality of life. We provide a global perspective and highlight Japanese, Canadian, and other regional examples where policies have been developed to increase renal physical activity and rehabilitation. We present recommendations targeting multiple stakeholders including nephrologists, nurses, allied health clinicians, organizations providing renal care and education, and renal program funders. CONCLUSIONS: We strongly recommend the nephrology community and people living with kidney disease take action to change policy now, rather than idly waiting for indisputable clinical trial evidence that increasing physical activity, strength, fitness, and function improves the lives of people living with kidney disease.

The role of exercise in improving patient-reported outcomes in individuals on dialysis: A scoping review.

Exercise improves objective measures of physical function in individuals on hemodialysis, but its effect on patient-reported outcomes (PROs) is largely unknown. We performed a scoping review to characterize the existing knowledge base on exercise and PROs in dialysis patients to make recommendations for future research. We searched Medline, Embase, Cochrane Database of Systematic Reviews; Cochrane Central Register of Controlled Trials, CINAHL, and SPORT Discus from inception to November 28, 2018 and then screened results for randomized controlled trials comparing aerobic/resistance exercise, or both, with no exercise in individuals on dialysis that reported results of any PRO. Of 1374 eligible studies, 25 studies met inclusion criteria. Study interventions included aerobic exercise (11 intradialytic and 3 home-based trials); intradialytic resistance exercise (seven studies) and combined aerobic and resistance exercise (six intradialytic and one facility-based trial). The PROs measured included health-related quality of life (n = 19), depression (n = 6), anxiety (n = 3), symptom burden (n = 4), sleep quality (n = 2), restless legs syndrome (n = 2), disability (n = 2), and self-reported physical activity level (n = 4). Only five studies included a PRO as a primary outcome. Studies primarily used broad/generic measures of health-related quality of life and the effect of exercise on symptoms remains relatively unexplored, particularly in peritoneal dialysis populations. Although limited, the role of exercise in improving restless legs was consistent and is a promising outcome for future study. A critical step to improving the quality of the research on this topic includes the use of validated and consistent PRO measures.

Central venous catheters for chronic hemodialysis: Is "last choice" never the "right choice"?

Since the publication of the first vascular access clinical practice guidelines in 1997, the global nephrology community has dedicated significant time and resources toward increasing the prevalence of arteriovenous fistulas and decreasing the prevalence of central venous catheters for hemodialysis. These efforts have been bolstered by observational studies showing an association between catheter use and increased patient morbidity and mortality. To date, however, no randomized comparisons of the outcomes of different forms of vascular access have been conducted. There is mounting evidence that much of the difference in patient outcomes may be explained by patient factors, rather than choice of vascular access. Some have called into question the appropriateness of fistula creation for certain patient populations, such as those with limited life expectancy and those at high risk of fistula-related complications. In this review, we explore the extent to which catheters and fistulas exhibit the characteristics of the "ideal" vascular access and highlight the significant knowledge gaps that exist in the current literature. Further studies, ideally randomized comparisons of different forms of vascular access, are required to better inform shared decision making.

A Clinical Risk Prediction Tool for 6-Month Mortality After Dialysis Initiation Among Older Adults.

BACKGROUND: Information on an individual's risk for death following dialysis therapy initiation may inform the decision to initiate maintenance dialysis for older adults. We derived and validated a clinical risk prediction tool for all-cause mortality among older adults during the first 6 months of maintenance dialysis treatment. STUDY DESIGN: Prediction model using retrospective administrative and clinical data. SETTING & PARTICIPANTS: We linked administrative and clinical data to define a cohort of 2,199 older adults (age ≥ 65 years) in Alberta, Canada, who initiated maintenance dialysis therapy (excluding acute kidney injury) in May 2003 to March 2012. CANDIDATE PREDICTORS: Demographics, laboratory data, comorbid conditions, and measures of health system use. OUTCOMES: All-cause mortality within 6 months of dialysis therapy initiation. ANALYTICAL APPROACH: Predicted mortality by logistic regression with 10-fold cross-validation. RESULTS: 375 (17.1%) older adults died within 6 months. We developed a 19-point risk score for 6-month mortality that included age 80 years or older (2 points), glomerular filtration rate of 10 to 14.9mL/min/1.73m2 (1 point) or ≥15mL/min/1.73m2 (3 points), atrial fibrillation (2 points), lymphoma (5 points), congestive heart failure (2 points), hospitalization in the prior 6 months (2 points), and metastatic cancer (3 points). Model discrimination (C statistic = 0.72) and calibration (Hosmer-Lemeshow χ2=10.36; P=0.2) were reasonable. As examples, a score < 5 equated to <25% of individuals dying in 6 months, whereas a score > 12 predicted that more than half the individuals would die in the first 6 months. LIMITATIONS: The tool has not been externally validated; thus, generalizability cannot be assessed. CONCLUSIONS: We used readily available clinical information to derive and internally validate a 7-variable tool to predict early mortality among older adults after dialysis therapy initiation. Following successful external validation, the tool may be useful as a clinical decision tool to aid decision making for older adults with kidney failure.

Sex differences in associations between insulin resistance, heart rate variability, and arterial stiffness in healthy women and men: a physiology study.

Diabetes confers greater cardiovascular risk to women than to men. Whether insulin-resistance-mediated risk extends to the healthy population is unknown. Measures of insulin resistance (fasting insulin, homeostatic model assessment, hemoglobin A1c, quantitative insulin sensitivity check index, glucose) were determined in 48 (56% female) healthy subjects. Heart rate variability (HRV) was calculated by spectral power analysis and arterial stiffness was determined using noninvasive applanation tonometry. Both were measured at baseline and in response to angiotensin II infusion. In women, there was a non-statistically significant trend towards increasing insulin resistance being associated with an overall unfavourable HRV response and increased arterial stiffness to the stressor, while men demonstrated the opposite response. Significant differences in the associations between insulin resistance and cardiovascular physiological profile exist between healthy women and men. Further studies investigating the sex differences in the pathophysiology of insulin resistance in cardiovascular disease are warranted.

Preemptive Correction of Arteriovenous Access Stenosis: A Systematic Review and Meta-analysis of Randomized Controlled Trials.

BACKGROUND: Preemptive correction of a stenosis in an arteriovenous (AV) access (fistula or graft) that is adequately providing hemodialysis (functional AV access) may prolong access survival as compared to waiting for signs of access dysfunction to intervene (deferred salvage). However, the evidence in support of preemptive intervention is controversial. We evaluated benefits and harms of preemptive versus deferred correction of AV access stenosis. STUDY DESIGN: Systematic review and meta-analysis of randomized controlled trials. SETTING & POPULATION: Adults receiving hemodialysis by a functional AV access. SELECTION CRITERIA FOR STUDIES: We searched the Cochrane Kidney and Transplant Specialised Register and EMBASE to October 15, 2015. INTERVENTION: Active access surveillance (flow measurement and Doppler or venous pressure) and preemptive correction of a newly identified stenosis versus routine clinical monitoring and deferred salvage, or preemptive correction of a known stenosis versus deferred salvage. OUTCOMES: Access loss (primary outcome) and thrombosis (overall and by access type), infection, mortality, hospitalization, and access-related procedures. RESULTS: We included 14 trials (1,390 participants; follow-up, 6-38 months). Relative to deferred salvage, preemptive correction of AV access stenosis had a nonsignificant effect on risk for access loss (risk ratio [RR], 0.81; 95% CI, 0.65-1.02; I(2)=0%) and a significant effect on risk for thrombosis (RR, 0.79; 95% CI, 0.65-0.97; I(2)=30%). Treatment effects were larger in fistulas than in grafts for both risk for access loss (subgroup difference, P=0.05) and risk for thrombosis (subgroup difference, P=0.002). Results were heterogeneous or imprecise for mortality, rates of access-related infections or procedures, and hospitalization. LIMITATIONS: Small number and size of primary studies limited analysis power. CONCLUSIONS: Preemptive stenosis correction in a functional AV access does not improve access longevity. Although preemptive stenosis correction may be promising in fistulas, existing evidence is insufficient to guide clinical practice and health policy.

Pre-emptive correction for haemodialysis arteriovenous access stenosis.

BACKGROUND: Guidelines recommend routine arteriovenous (AV) graft and fistula surveillance (technology-based screening) in addition to clinical monitoring (physical examination) for early identification and pre-emptive correction of a stenosis before the access becomes dysfunctional. However, consequences on patient-relevant outcomes of pre-emptive correction of a stenosis in a functioning access as opposed to deferred correction, i.e. correction postponed to when the access becomes dysfunctional, are uncertain. OBJECTIVES: We aimed to evaluate 1) whether pre-emptive correction of an AV access stenosis improves clinically relevant outcomes; 2) whether the effects of pre-emptive correction of an AV access stenosis differ by access type (fistula versus graft), aim (primary and secondary prophylaxis), and surveillance method for primary prophylaxis (Doppler ultrasound for the screening of functional and anatomical changes versus measurement of the flow in the access); and 3) whether other factors (dialysis duration, access location, configuration or materials, algorithm for referral for intervention, intervention strategies (surgical versus radiological or other), or study design) explain the heterogeneity that might exist in the effect estimates. SEARCH METHODS: We searched the Cochrane Kidney and Transplant Specialised Register to 30 November 2015 using search terms relevant to this review. SELECTION CRITERIA: We included all studies of any access surveillance method for early identification and pre-emptive treatment of an AV access stenosis. DATA COLLECTION AND ANALYSIS: We extracted data on potentially remediable and irremediable failure of the access (i.e. thrombosis and access loss respectively); infection and mortality; and resource use (hospitalisation, diagnostic and intervention procedures). Analysis was by a random effects model and results expressed as risk ratio (RR), hazard ratio (HR) or incidence rate ratio (IRR) with 95% confidence intervals (CI). MAIN RESULTS: We identified 14 studies (1390 participants), nine enrolled adults without a known access stenosis (primary prophylaxis; three studies including people using fistulas) and five enrolled adults with a documented stenosis in a non-dysfunctional access (secondary prophylaxis; three studies in people using fistulas). Study follow-up ranged from 6 to 38 months, and study size ranged from 58 to 189 participants. In low- to moderate-quality evidence (based on GRADE criteria) in adults treated with haemodialysis, relative to no surveillance and deferred correction, surveillance with pre-emptive correction of an AV stenosis reduced the risk of thrombosis (RR 0.79, 95% CI 0.65 to 0.97; I² = 30%; 18 study comparisons, 1212 participants), but had imprecise effect on the risk of access loss (RR 0.81, 95% CI 0.65 to 1.02; I² = 0%; 11 study comparisons, 972 participants). In analyses subgrouped by access type, pre-emptive stenosis correction did not reduce the risk of thrombosis (RR 0.95, 95% CI 0.8 to 1.12; I² = 0%; 11 study comparisons, 697 participants) or access loss in grafts (RR 0.9, 95% CI 0.71 to 1.15; I² = 0%; 7 study comparisons; 662 participants), but did reduce the risk of thrombosis (RR 0.5, 95% CI 0.35 to 0.71; I² = 0%; 7 study comparisons, 515 participants) and the risk of access loss in fistulas (RR 0.5, 95% CI 0.29 to 0.86; I² = 0%; 4 studies; 310 participants). Three of the four studies reporting access loss data in fistulas (199 participants) were conducted in the same centre. Insufficient data were available to assess whether benefits vary by prophylaxis aim in fistulas (i.e. primary and secondary prophylaxis). Although the magnitude of the effects of pre-emptive stenosis correction was considerable for patient-centred outcomes, results were either heterogeneous or imprecise. While pre-emptive stenosis correction may reduce the rates of hospitalisation (IRR 0.54, 95% CI 0.31 to 0.93; I² = 67%; 4 study comparisons, 219 participants) and use of catheters (IRR 0.58, 95% CI 0.35 to 0.98; I² = 53%; 6 study comparisons, 394 participants), it may also increase the rates of diagnostic procedures (IRR 1.78, 95% CI 1.18 to 2.67; I² = 62%; 7 study comparisons, 539 participants), infection (IRR 1.74, 95% CI 0.78 to 3.91; I² = 0%; 3 studies, 248 participants) and mortality (RR 1.38, 95% CI 0.91 to 2.11; I² = 0%; 5 studies, 386 participants).In general, risk of bias was high or unclear in most studies for many domains we assessed. Four studies were published after 2005 and only one had evidence of registration within a trial registry. No study reported information on authorship and/or involvement of the study sponsor in data collection, analysis, and interpretation. AUTHORS' CONCLUSIONS: Pre-emptive correction of a newly identified or known stenosis in a functional AV access does not improve access longevity. Although pre-emptive stenosis correction may be promising in fistulas existing evidence is insufficient to guide clinical practice and health policy. While pre-emptive stenosis correction may reduce the risk of hospitalisation, this benefit is uncertain whereas there may be a substantial increase (i.e. 80%) in the use of access-related procedures and procedure-related adverse events (e.g. infection, mortality). The net effects of pre-emptive correction on harms and resource use are thus unclear.

The effect of citrate dialysate on intradialytic heparin dose in haemodialysis patients: study design of a randomised controlled trial.

BACKGROUND: Unfractionated heparin is the most common anticoagulant used in haemodialysis (HD), although it has many potential adverse effects. Citrate dialysate (CD) has an anticoagulant effect which may allow reduction in cumulative heparin dose (CHD) compared to standard acetate dialysate (AD). METHODS: This double-blinded, randomised, cross-over trial of chronic haemodialysis patients determines if CD allows reduction in CHD during HD compared with AD. After enrolment, intradialytic heparin is minimised during a two-week run-in period using a standardised protocol based on a visual clotting score. Patients still requiring intradialytic heparin after the run-in period are randomised to two weeks of HD with AD followed by two weeks of CD (Sequence 1) or two weeks of HD with CD followed by two weeks of AD (Sequence 2). The primary outcome is the change in CHD with CD compared with AD. Secondary outcomes include metabolic and haemodynamic parameters, and dialysis adequacy. DISCUSSION: This randomised controlled trial will determine the impact of CD compared with AD on CHD during HD. TRIAL REGISTRATION: ClinicalTrials.gov NCT01466959.

Arteriovenous fistula survival and needling technique: long-term results from a randomized buttonhole trial.

BACKGROUND: We previously have shown that buttonhole needling is associated with a reduction in hematoma and postulated that buttonhole needling may increase long-term survival of an arteriovenous fistula (AVF). The purpose of this study was to evaluate AVF survival and complications in buttonhole versus standard needling. STUDY DESIGN: Long-term follow up of a randomized controlled trial in which participants were randomly assigned to standard or buttonhole needling and followed up until the AVF was abandoned or the study end date. SETTING & PARTICIPANTS: 140 long-term hemodialysis patients in Calgary, Alberta. INTERVENTION: Buttonhole needling with median time of exposure to the intervention of 13.2 (IQR, 7.8-19.4) months. OUTCOMES & MEASUREMENTS: Patients were prospectively followed up for study outcomes. Median follow-up times were 17.2 (IQR, 11.9-37.8) and 19.2 (IQR, 12.5-41.0) months for standard and buttonhole needling, respectively (P=0.2). The primary outcome was median access survival in months. Other outcomes included assisted and unassisted patency rates, rates of surgical and radiologic interventions, and time to abandonment (months) of buttonhole. RESULTS: Baseline characteristics were similar. The primary outcome, median access survival, was similar in both groups: 16.0 (IQR, 10.6-29.3) and 18.4 (IQR, 10.9-32.7) months for standard and buttonhole needling, respectively (P=0.2). There were 7 (10.1%) and 6 (8.6%) thromboses with standard and buttonhole needling, respectively (P=0.6). Median fistulogram rates were similar between techniques (P=0.2 with intention-to-treat analysis). Most patients (46 of 70) abandoned buttonhole needling by a median of 11.3 (IQR, 4.8-18.2) months. Median time to first infection for buttonhole needling was 11.1 (IQR, 4.9-30.0) months. There were no infections in standard needling of AVFs. LIMITATIONS: Findings are limited to patients needled by multiple hemodialysis nurses and not applicable to self-needlers. CONCLUSIONS: AVFs with buttonhole needling did not have improved survival. The lack of survival benefit and higher risk of infection should be noted when promoting buttonhole needling.

The VITAH trial VITamin D supplementation and cardiac Autonomic tone in Hemodialysis: a blinded, randomized controlled trial.

BACKGROUND: Patients with end-stage kidney disease (ESKD) have a high rate of mortality and specifically an increased risk of sudden cardiac death (SCD). Impaired cardiac autonomic tone is associated with elevated risk of SCD. Moreover, patients with ESKD are often vitamin D deficient, which we have shown may be linked to autonomic dysfunction in humans. To date, it is not known whether vitamin D supplementation normalizes cardiac autonomic function in the high-risk ESKD population. The VITamin D supplementation and cardiac Autonomic tone in Hemodialysis (VITAH) randomized trial will determine whether intensive vitamin D supplementation therapies improve cardiac autonomic tone to a greater extent than conventional vitamin D supplementation regimens in ESKD patients requiring chronic hemodialysis. METHODS/DESIGN: A total of 60 subjects with ESKD requiring thrice weekly chronic hemodialysis will be enrolled in this 2x2 crossover, blinded, randomized controlled trial. Following a 4-week washout period from any prior vitamin D therapy, subjects are randomized 1:1 to intensive versus standard vitamin D therapy for 6 weeks, followed by a 12-week washout period, and finally the remaining treatment arm for 6 weeks. Intensive vitamin D treatment includes alfacalcidiol (activated vitamin D) 0.25 mcg orally with each dialysis session combined with ergocalciferol (nutritional vitamin D) 50 000 IU orally once per week and placebo the remaining two dialysis days for 6 weeks. The standard vitamin D treatment includes alfacalcidiol 0.25 mcg orally combined with placebo each dialysis session per week for 6 weeks. Cardiac autonomic tone is measured via 24 h Holter monitor assessments on the first dialysis day of the week every 6 weeks throughout the study period. The primary outcome is change in the low frequency: high frequency heart rate variability (HRV) ratio during the first 12 h of the Holter recording at 6 weeks versus baseline. Secondary outcomes include additional measures of HRV. The safety of intensive versus conventional vitamin D supplementation is also assessed. DISCUSSION: VITAH will determine whether an intensive vitamin D supplementation regimen will improve cardiac autonomic tone compared to conventional vitamin D supplementation and will assess the safety of these two supplementation regimens in ESKD patients receiving chronic hemodialysis. TRIAL REGISTRATION: ClinicalTrials.gov, NCT01774812.

25-Hydroxyvitamin D status, arterial stiffness and the renin-angiotensin system in healthy humans.

Vitamin D deficiency is associated with increased arterial stiffness. We sought to clarify the influence of vitamin D in modulating angiotensin II-dependent arterial stiffness. Thirty-six healthy subjects (33 ± 2 years, 67% female, mean 25-hydroxyvitamin D 69 ± 4 nmol/L) were studied in high salt balance. Arterial stiffness, expressed as brachial pulse wave velocity (bPWV) and aortic augmentation index (AIx), was measured by tonometry at baseline and in response to angiotensin II infusion (3 ng/kg/min × 30 min then 6 ng/kg/min × 30 min). The primary outcome was change in bPWV after an angiotensin II challenge. Results were analyzed according to plasma 25-hydroxyvitamin D status: deficient (<50 nmol/L) and sufficient (≥ 50 nmol/L). There were no differences in baseline arterial stiffness between vitamin D deficient (25-hydroxyvitamin D 40 ± 2 nmol/L) and sufficient (25-hydroxyvitamin D 80 ± 4 nmol/L) groups. Compared with sufficient vitamin D status, vitamin D deficiency was associated with a decreased arterial response to angiotensin II challenge (Δbrachial pulse wave velocity: 0.48 ± 0.44 m/s versus 1.95 ± 0.22 m/s, p=0.004; Δaortic augmentation index: 9.4 ± 3.4% versus 14.2 ± 2.7%, p=0.3), which persisted for brachial pulse wave velocity response after adjustment for covariates (p=0.03). Vitamin D deficiency is associated with increased arterial stiffness in healthy humans, possibly through an angiotensin II-dependent mechanism.

Associations between hemodialysis access type and clinical outcomes: a systematic review.

Clinical practice guidelines recommend an arteriovenous fistula as the preferred vascular access for hemodialysis, but quantitative associations between vascular access type and various clinical outcomes remain controversial. We performed a systematic review of cohort studies to evaluate the associations between type of vascular access (arteriovenous fistula, arteriovenous graft, and central venous catheter) and risk for death, infection, and major cardiovascular events. We searched MEDLINE, EMBASE, and article reference lists and extracted data describing study design, participants, vascular access type, clinical outcomes, and risk for bias. We identified 3965 citations, of which 67 (62 cohort studies comprising 586,337 participants) met our inclusion criteria. In a random effects meta-analysis, compared with persons with fistulas, those individuals using catheters had higher risks for all-cause mortality (risk ratio=1.53, 95% CI=1.41-1.67), fatal infections (2.12, 1.79-2.52), and cardiovascular events (1.38, 1.24-1.54). Similarly, compared with persons with grafts, those individuals using catheters had higher risks for mortality (1.38, 1.25-1.52), fatal infections (1.49, 1.15-1.93), and cardiovascular events (1.26, 1.11-1.43). Compared with persons with fistulas, those individuals with grafts had increased all-cause mortality (1.18, 1.09-1.27) and fatal infection (1.36, 1.17-1.58), but we did not detect a difference in the risk for cardiovascular events (1.07, 0.95-1.21). The risk for bias, especially selection bias, was high. In conclusion, persons using catheters for hemodialysis seem to have the highest risks for death, infections, and cardiovascular events compared with other vascular access types, and patients with usable fistulas have the lowest risk.

Exercise perceptions and practices of people receiving peritoneal dialysis: An international cross-sectional survey.

BACKGROUND: Low physical activity and functional impairment are prevalent and unaddressed in people receiving peritoneal dialysis (PD). Exercise has been shown to improve physical function and mental health for people with kidney disease. METHODS: Cross-sectional descriptive survey aimed at identifying the exercise and physical activity perceptions and practice patterns of people receiving PD. The survey was developed and pretested with persons living with kidney disease, PD clinicians and exercise specialists. RESULTS: There were 108 respondents (people receiving PD) with the majority from Canada (68%) and the United Kingdom (25%). Seventy-one per cent were engaged in physical activity two or more times per week. Most (91.8%) believed that physical activity is beneficial, and 61.7% reported healthcare provider discussion about physical activity. Perceptions regarding weightlifting restrictions varied: 76% were told not to lift weight with a maximum amount ranging from 2 kg to 45 kg. Few (28%) were instructed to drain PD fluid prior to physical activity. Mixed advice regarding swimming ability was common (44% were told they could swim and 44% were told they should not). CONCLUSIONS: Knowledge gaps suggest that education for both healthcare providers and patients is needed regarding the practice of exercise for people living with PD. Common areas of confusion include the maximum weight a person should lift, whether exercise was safe with or without intrabdominal PD fluid in situ and whether swimming is allowed. Further research is needed to provide patients with evidence-based recommendations rather than defaulting to restricting activity.

Emergency Department Use Among Adults Receiving Dialysis.

Importance: People with kidney failure receiving maintenance dialysis visit the emergency department (ED) 3 times per year on average, which is 3- to 8-fold more often than the general population. Little is known about the factors that contribute to potentially preventable ED use in this population. Objective: To identify the clinical and sociodemographic factors associated with potentially preventable ED use among patients receiving maintenance dialysis. Design, Setting, and Participants: This cohort study used linked administrative health data within the Alberta Kidney Disease Network to identify adults aged 18 years or older receiving maintenance dialysis (ie, hemodialysis or peritoneal dialysis) between April 1, 2010, and March 31, 2019. Patients who had been receiving dialysis for more than 90 days were followed up from cohort entry (defined as dialysis start date plus 90 days) until death, outmigration from the province, receipt of a kidney transplant, or end of study follow-up. The Andersen behavioral model of health services was used as a conceptual framework to identify variables related to health care need, predisposing factors, and enabling factors. Data were analyzed in March 2024. Main Outcomes and Measures: Rates of all-cause ED encounters and potentially preventable ED use associated with 4 kidney disease-specific ambulatory care-sensitive conditions (hyperkalemia, heart failure, volume overload, and malignant hypertension) were calculated. Multivariable negative binomial regression models were used to examine the association between clinical and sociodemographic factors and rates of potentially preventable ED use. Results: The cohort included 4925 adults (mean [SD] age, 60.8 [15.5] years; 3071 males [62.4%]) with kidney failure receiving maintenance hemodialysis (3183 patients) or peritoneal dialysis (1742 patients) who were followed up for a mean (SD) of 2.5 (2.0) years. In all, 3877 patients had 34 029 all-cause ED encounters (3100 [95% CI, 2996-3206] encounters per 1000 person-years). Of these, 755 patients (19.5%) had 1351 potentially preventable ED encounters (114 [95% CI, 105-124] encounters per 1000 person-years). Compared with patients with a nonpreventable ED encounter, patients with a potentially preventable ED encounter were more likely to be in the lowest income quintile (38.8% vs 30.9%; P < .001); to experience heart failure (46.8% vs 39.9%; P = .001), depression (36.6% vs 32.5%; P = .03), and chronic pain (60.1% vs 54.9%; P = .01); and to have a longer duration of dialysis (3.6 vs 2.6 years; P < .001). In multivariable regression analyses, potentially preventable ED use was higher for younger adults (incidence rate ratio [IRR], 1.69 [95% CI, 1.33-2.15] for those aged 18 to 44 years) and patients with chronic pain (IRR, 1.35 [95% CI, 1.14-1.61]), greater material deprivation (IRR, 1.57 [95% CI, 1.16-2.12]), a history of hyperkalemia (IRR, 1.31 [95% CI, 1.09-1.58]), and historically high ED use (ie, ≥3 ED encounters in the prior year; IRR, 1.46 [95% CI, 1.23-1.73). Conclusions and Relevance: In this study of adults receiving maintenance dialysis in Alberta, Canada, among those with ED use, 1 in 5 had a potentially preventable ED encounter; reasons for such encounters were associated with both psychosocial and medical factors. The findings underscore the need for strategies that address social determinants of health to avert potentially preventable ED use in this population.

Randomized Controlled Trial of the Effect of an Exercise Rehabilitation Program on Symptom Burden in Maintenance Hemodialysis: A Clinical Research Protocol.

Background: People receiving hemodialysis experience high symptom burden that contributes to low functional status and poor health-related quality of life. Management of symptoms is a priority for individuals receiving hemodialysis but limited effective treatments exist. There is emerging evidence that exercise programming can improve several common dialysis-related symptoms. Objective: The primary aim of this study is to evaluate the effect of an exercise rehabilitation program on symptom burden in individuals receiving maintenance hemodialysis. Design: Multicenter, randomized controlled, 1:1 parallel, open label, prospective blinded end point trial. Setting: Three facility-based hemodialysis units in Winnipeg, Manitoba, Canada. Participants: Adults aged 18 years or older with end-stage kidney disease receiving facility-based maintenance hemodialysis for more than 3 months, with at least 1 dialysis-related symptom as indicated by the Dialysis Symptom Index (DSI) severity score >0 (n = 150). Intervention: Supervised 26-week exercise rehabilitation program and 60 minutes of cycling during hemodialysis thrice weekly. Exercise intensity and duration were supervised and individualized by the kinesiologist as per participant baseline physical function with gradual progression over the course of the intervention. Control: Usual hemodialysis care (no exercise program). Measurements: Our primary outcome is change in symptom burden at 12 weeks as measured by the DSI severity score. Secondary outcomes include change in modified DSI severity score (includes 10 symptoms most plausible to improve with exercise), change in DSI severity score at 26 and 52 weeks; time to recover post-hemodialysis; health-related quality of life measured using EuroQol (EQ)-5D-5L; physical activity behavior measured by self-report (Godin-Shepherd questionnaire) and triaxial accelerometry; exercise capacity (shuttle walk test); frailty (Fried); self-efficacy for exercise; and 1-year hospitalization and mortality. Methods: Change in primary outcome will be compared between groups by independent 2-tailed t test or Mann-Whitney U test depending on data distribution and using generalized linear mixed models, with study time point as a random effect and adjusted for baseline DSI score. Similarly, change in secondary outcomes will be compared between groups over time using appropriate parametric and nonparametric statistical tests depending on data type and distribution. Limitations: The COVID-19 pandemic restrictions on clinical research at our institution delayed completion of target recruitment and prevented collection of accelerometry and physical function outcome data for 15 months until restrictions were lifted. Conclusions: The application of an exercise rehabilitation program to improve symptom burden in individuals on hemodialysis may ameliorate common symptoms observed in individuals on hemodialysis and result in improved quality of life and reduced disability and morbidity over the long term. Importantly, this pragmatic study, with a standardized exercise intervention that is adaptable to baseline physical function, addresses an important gap in both clinical care of hemodialysis patients and our current knowledge.

Contexte: Les personnes sous hémodialyse éprouvent un grand nombre de symptômes qui contribuent à un faible état fonctionnel et à une mauvaise qualité de vie liée à la santé. La prise en charge des symptômes est une priorité pour les personnes sous hémodialyse, mais les traitements efficaces sont limités. De nouvelles preuves montrent que l'adoption d'un programme d'exercice permettrait d'améliorer plusieurs symptômes courants liés à la dialyse. Objectifs: Le principal objectif de cette étude est d'évaluer l'effet d'un programme de rééducation par l'exercice sur le fardeau des symptômes chez les personnes recevant une hémodialyse d'entretien. Conception: Essai clinique prospectif randomisé-contrôlé, en aveugle, en parallèle 1:1 et ouvert, multicentrique. Cadre: Trois unités d'hémodialyse de Winnipeg, au Manitoba (Canada). Sujets: Des adultes atteints d'insuffisance rénale terminale qui reçoivent des traitements d'hémodialyse d'entretien en centre depuis plus de trois mois et qui présentent au moins un symptôme lié à la dialyse, tel qu'indiqué par un score de gravité de l'indice des symptômes de la dialyse (Dialysis Symptom Index) supérieur à zéro (n = 150). Intervention: Programme supervisé de rééducation par l'exercice d'une durée de 26 semaines et 60 minutes de vélo trois fois par semaine pendant l'hémodialyse. L'intensité et la durée de l'exercice ont été supervisées par un kinésiologue qui les a ensuite personnalisées en fonction de la forme physique initiale du participant en prévoyant une progression graduelle tout au long de l'intervention. Groupe témoin: Soins habituels d'hémodialyse (sans programme d'exercice). Mesures: Notre principal critère de jugement est un changement dans le fardeau lié aux symptômes après 12 semaines, tel que mesuré par le score de gravité de l'indice des symptômes de dialyse (ISD). Les critères d'évaluation secondaires comprennent un changement du score modifié de gravité de l'ISD (portant sur 10 symptômes les plus plausibles de s'améliorer avec l'exercice), la modification du score de gravité de l'ISD après 26 et 52 semaines, le temps de récupération après l'hémodialyse, la qualité de vie liée à la santé mesurée par le questionnaire EQ5D-5L, le comportement lié à l'activité physique mesuré par autoévaluation (questionnaire Godin-Shepherd) et par accéléromètre triaxial, la capacité d'effort (test de marche navette), la fragilité (Fried), le sentiment d'efficacité autodéclaré face à l'exercice, ainsi que les hospitalisations et la mortalité à un an. Méthodologie: Les changements pour le principal critère de jugement seront comparés entre les groupes par un test t bilatéral indépendant ou un test U de Mann-Whitney en fonction de la distribution des données, ainsi qu'à l'aide de modèles linéaires mixtes généralisés avec un point temporel de l'étude comme effet aléatoire et corrigé en fonction du score ISD initial. Les changements dans les résultats secondaires seront comparés entre les groupes au fil du temps à l'aide des tests statistiques paramétriques et non paramétriques appropriés selon le type de données et la distribution. Limites: Les restrictions liées à la pandémie de COVID-19 dans notre établissement ont retardé le recrutement des cibles et empêché pendant 15 mois la collecte de données sur les résultats mesurés par l'accéléromètre et les mesures de la fonction physique, soit jusqu'à ce que les restrictions soient levées. Conclusion: L'adoption d'un programme de rééducation par l'exercice visant à réduire le fardeau lié aux symptômes chez les personnes sous hémodialyse peut améliorer les symptômes courants observés dans cette population et se traduire par une amélioration de la qualité de vie et une réduction de l'invalidité et de la morbidité à long terme. Il convient de noter que cet essai pragmatique, avec son intervention d'exercice standardisée adaptable à la condition physique initiale de la personne, comble une lacune importante dans les soins cliniques des patients sous hémodialyse et dans nos connaissances actuelles.

The Association Between Intradialytic Symptom Clusters and Recovery Time in Patients Undergoing Maintenance Hemodialysis: An Exploratory Analysis.

Background: Individuals receiving hemodialysis often experience concurrent symptoms during treatment and frequently report feeling unwell after dialysis. The degree to which intradialytic symptoms are related, and which specific symptoms may impair health-related quality of life (HRQoL) is uncertain. Objectives: To explore intradialytic symptoms clusters, and the relationship between intradialytic symptom clusters with dialysis treatment recovery time and HRQoL. Design/setting: We conducted a post hoc analysis of a prospective cohort study of 118 prevalent patients receiving hemodialysis in two centers in Calgary, Alberta and Hamilton, Ontario, Canada. Participants: Adults receiving hemodialysis treatment for at least 3 months, not scheduled for a modality change within 6 weeks of study commencement, who could provide informed consent and were able to complete English questionnaires independently or with assistance. Methods: Participants self-reported the presence (1 = none to 5 = very much) of 10 symptoms during each dialysis treatment, the time it took to recover from each treatment, and weekly Kidney Disease Quality of Life 36-Item-Short Form (KDQoL-36) assessments. Principal component analysis identified clusters of intradialytic symptoms. Mixed-effects, ordinal and linear regression examined the association between symptom clusters and recovery time (categorized as 0, >0 to 2, >2 to 6, or >6 hours), and the physical component and mental component scores (PCS and MCS) of the KDQoL-36. Results: One hundred sixteen participants completed 901 intradialytic symptom questionnaires. The most common symptom was lack of energy (56% of treatments). Two intradialytic symptom clusters explained 39% of the total variance of available symptom data. The first cluster included bone or joint pain, muscle cramps, muscle soreness, feeling nervous, and lack of energy. The second cluster included nausea/vomiting, diarrhea and chest pain, and headache. The first cluster (median score: -0.56, 25th to 75th percentile: -1.18 to 0.55) was independently associated with longer recovery time (odds ratio [OR] 1.62 per unit difference in score, 95% confidence interval [CI]: 1.23-2.12) and decreased PCS (-0.72 per unit difference in score, 95% CI: -1.29 to -0.15) and MCS scores (-0.82 per unit difference in score, 95% CI: -1.48 to -0.16), whereas the second cluster was not (OR 1.24, 95% CI: 0.97-1.58; PCS 0.19, 95% CI -0.46 to 0.83; MCS -0.72, 95% CI: -1.50 to 0.06). Limitations: This was an exploratory analysis of a small data set from 2 centers. Further work is needed to externally validate these findings to confirm intradialytic symptom clusters and the generalizability of our findings. Conclusions: Intradialytic symptoms are correlated. The presence of select intradialytic symptoms may prolong the time it takes for a patient to recover from a dialysis treatment and impair HRQoL.

Contexte: Il arrive fréquemment que les personnes qui reçoivent des traitements d'hémodialyse éprouvent des symptômes concomitants pendant la dialyze et signalent un malaise après le traitement. On en sait toutefois peu sur le degré de corrélation de ce malaise avec les symptômes intradialytiques et sur les symptômes précis qui peuvent altérer la qualité de vie liée à la santé (QVLS). Objectifs: Explorer différents groupes de symptômes intradialytiques et la relation de ceux-ci avec le temps de récupération post-dialyze et la QVLS. Cadre et conception de l'étude: Nous avons procédé à une analyze post-hoc d'une étude de cohorte prospective portant sur 118 patients prévalents recevant une hémodialyse dans deux centers, soit à Calgary (Alberta) et à Hamilton (Ontario) au Canada. Sujets: Des adultes qui recevaient des traitements d'hémodialyse depuis au moins trois mois ­ sans changement de modalité prévu dans les six semaines suivant le début de l'étude ­ qui pouvaient donner leur consentement éclairé et qui étaient en mesure de remplir des questionnaires en anglais de façon autonome ou avec de l'aide. Méthodologie: Pour chaque traitement de dialyze, les participants devaient autoévaluer le degré de présence (de 1 [non présent] à 5 [très présent]) de dix symptômes et le temps nécessaire pour récupérer de chaque traitement, puis remplir des évaluations hebdomadaires à l'aide du questionnaire KDQoL-36. Une analyze des composantes principales a permis de définir des groupes de symptômes intradialytiques. Une régression à effets mixtes, ordinale et linéaire, a servi à examiner l'association entre les groupes de symptômes et le temps de récupération (0 heure; de 0 à 2 heures; de 2 à 6 hures; plus de 6 heures), et les scores des composantes physiques et psychologiques du KDQoL-36. Résultats: Cent seize patients ont rempli un total de 901 questionnaires sur les symptômes intradialytiques. Le symptôme le plus fréquemment déclaré était le manque d'énergie (56 % des traitements). Deux groupes de symptômes intradialytiques ont expliqué 39 % de la variance totale des données disponibles sur les symptômes. Le premier groupe comprenait des douleurs osseuses ou articulaires, des crampes musculaires, des douleurs musculaires, une sensation de nervosité et un manque d'énergie. Le deuxième groupe comprenait des nausées/vomissements, de la diarrhée, des douleurs thoraciques et des maux de tête. Le premier groupe (score médian : ­0,56; du 25e au 75e percentile : ­1, 18 à 0,55) a été indépendamment associé à un temps de récupération plus long (rapport de cotes : 1,62 par unité de différence de score; IC 95 % : 1,23 à 2,12) et à une diminution des scores des composantes physiques (RC : ­0,72; IC 95 % : ­1, 29 à ­0,15) et des scores des composantes psychologiques (RC : ­0,82; IC 95 % : ­1, 48 à ­0,16). Le deuxième groupe n'a pas été associé avec le temps de récupération (RC : 1,24; IC 95 % : 0,97 à 1,58) ni avec le score des composantes physiques (RC : 0,19; IC 95 % : ­0,46 à 0,83) et les scores des composantes psychologiques (RC : ­0,72; IC 95 % : ­1, 50 à 0,06). Limites: Il s'agissait d'une analyze exploratoire d'un petit ensemble de données provenant de deux centers. D'autres études externes sont nécessaires pour valider ces résultats et, ainsi, confirmer nos groupes de symptômes intradialytiques et la généralisabilité de nos résultats. Conclusion: Les symptômes intradialytiques sont corrélés. La présence de certains symptômes intradialytiques peut prolonger le temps de récupération post-dialyze et altérer la qualité de vie des patients.