Implications of Implementing the 2021 CKD-EPI Equation Without Race on Managing Patients With Kidney Disease in British Columbia, Canada.

Introduction: We investigated the implications of implementing race-free Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) 2021 equation among real-world patients with chronic kidney disease (CKD) from British Columbia (BC), Canada. Methods: This study included nondialysis-dependent patients with CKD aged ≥19 years who were registered in the Patient Records and Outcome Management Information System (PROMIS) as of March 31, 2016 (index date) with ≥1 serum creatinine measurement within 1 year before the index date. Patients with a history of kidney transplantation before the index date were excluded. CKD-EPI 2021 versus 2009 equation was the exposure variable. Difference in mean estimated glomerular filtration rate (eGFR) and number (%) of patients reclassified to a different eGFR category were estimated. We used Fine and Gray subdistribution hazard model to investigate the association between change in eGFR category and progression to kidney failure (incident maintenance dialysis or kidney transplantation) within 2 years. Results: A total of 11,604 patients (median age 73 years, 52% male) were included. Compared to the 2009 equation, eGFR from 2021 equation was on average 2.7 ml/min per 1.73 m2 higher. Variation was higher among males. Overall, ∼17% of the study sample were reclassified to a category with higher eGFR by 2021 equation (switchers). The highest proportion (28%) of patients were reclassified from G5 to G4. The risk of progressing to kidney failure was 22% less among switchers compared to nonswitchers; adjusted subdistribution hazard ratio (HR) (95% confidence interval [CI]) is 0.78 (0.65, 0.94). Conclusion: CKD-EPI 2021 equation appeared to provide higher eGFR compared to 2009 equation. This higher eGFR values appeared to be concordant with subsequent real-world CKD progression outcomes. Higher eGFR from the 2021 equation may have substantial clinical implications in both diagnosis as well as long-term care of patients with CKD.

Assessing Discharge Communication and Follow-up of Acute Kidney Injury in British Columbia: A Retrospective Chart Review.

Background and objective: Acute kidney injury (AKI) affects up to 20% of hospitalizations and is associated with chronic kidney disease, cardiovascular disease, increased mortality, and increased health care costs. Proper documentation of AKI in discharge summaries is critical for optimal monitoring and treatment of these patients once discharged. Currently, there is limited literature evaluating the quality of discharge communication after AKI. This study aimed to evaluate the accuracy and quality of documentation of episodes of AKI at a tertiary care center in British Columbia, Canada. Methods design setting patients and measurements: This was a retrospective chart review study of adult patients who experienced AKI during hospital admission between January 1, 2018, and December 31, 2018. Laboratory data were used to identify all admissions to the cardiac and general medicine ward complicated by AKI defined by the Kidney Disease Improving Global Outcomes (KDIGO) criteria. A random sample of 300 AKI admissions stratified by AKI severity (eg, stages 1, 2, and 3) were identified for chart review. Patients were excluded if they required ongoing renal replacement therapy after admission, had a history of kidney transplant, died during their admission, or did not have a discharge summary available. Discharge summaries were reviewed for documentation of the following: presence of AKI, severity of AKI, AKI status at discharge, practitioner and laboratory follow-up plans, and medication changes. Results: A total of 1076 patients with 1237 AKI admissions were identified. Of the 300 patients selected for discharge summary review, 38 met exclusion criteria. In addition, AKI was documented in 140 (53%) discharge summaries and was more likely to be documented in more severe AKI: stage 1, 38%; stage 2, 51%; and stage 3, 75%. Of those with their AKI documented, 94 (67%) documented AKI severity, and 116 (83%) mentioned the AKI status or trajectory at the time of discharge. A total of 239 (91%) of discharge summaries mentioned a follow-up plan with a practitioner, but only 23 (10%) had documented follow-up with nephrology. Patients with their AKI documented were more likely to have nephrology follow-up than those without AKI documented (17% vs 1%). Regarding laboratory investigations, 92 (35%) of the summaries had documented recommendations. In summaries that included medications typically held during AKI, only about half made specific reference to those medications being held, adjusted, or documented a post-discharge plan for that medication. For those with nonsteroidal anti-inflammatory drugs (NSAIDs) listing, 64% of discharge summaries mentioned holding, and 9% mentioned a discharge plan. For those with angiotensin converting enzyme inhibitor (ACEi)/angiotensin II receptor blocker (ARB) listing, 38% mentioned holding these medications, and 46% mentioned a discharge plan. In summaries with diuretics listed, 35% mentioned holding, and 51% included a discharge plan. Conclusions and limitations: We found suboptimal quality and completeness of discharge reporting in patients hospitalized with AKI. This may contribute to inadequate follow-up and post-hospitalization care for this patient population. Strategies are required for increasing the presence and quality of AKI reporting in discharge summaries. Limitations include our definition of AKI based on lab criteria, which may have missed some of the injuries that met the criteria based on urine output. Another limitation is that our definition of AKI based on the highest and lowest creatinine during admission may have led to some overclassification. In addition, without outpatient laboratories, it is possible that we have not captured the true baseline creatinine in some patients.

Contexte et objectif: L'insuffisance rénale aiguë (IRA) complique jusqu'à 20 % des hospitalisations; elle est associée à l'insuffisance rénale chronique, aux maladies cardiovasculaires, à une mortalité accrue et à une augmentation des coûts de santé. La documentation appropriée de l'IRA dans les résumés de départ est essentielle pour optimiser la surveillance et le traitement des patients après leur sortie de l'hôpital. Il existe peu de littérature évaluant la qualité de la documentation de l'IRA dans les résumés de départ. Cette étude visait à évaluer l'exactitude et la qualité de la documentation des épisodes d'IRA dans un center de soins tertiaires de la Colombie-Britannique (Canada). Méthodologie conception et cadre de l'étude sujets et mesures: Il s'agit d'une étude rétrospective des dossiers de patients adultes ayant présenté une IRA au cours de leur admission à l'hôpital entre le 1er janvier 2018 et le 31 décembre 2018. Les données de laboratoire ont été utilisées pour répertorier toutes les admissions compliquées par une IRA (définie par les critères KDIGO) dans les services de cardiologie et de médecine générale. Un échantillon aléatoire de 300 admissions avec IRA stratifiée selon sa gravité (p. ex., stade, 1, 2 et 3) a été constitué pour l'examen des dossiers. Ont été exclus les patients qui avaient eu besoin d'une thérapie de suppléance rénale continue après leur admission, ceux qui avaient des antécédents de transplantation rénale, ceux qui étaient décédés pendant leur admission et ceux pour qui aucun résumé de départ n'était disponible. Les résumés de départ ont été examinés à la recherche d'une mention des éléments suivants : présence d'une IRA, gravité de l'IRA, statut de l'IRA à la sortie, plans de suivi pour les tests de laboratoire et suivi avec un praticien, changements dans la médication. Résultats: En tout, 1 076 patients avec un total de 1 237 admissions avec IRA ont été identifiés. Parmi les 300 patients sélectionnés pour l'examen du résumé de départ, 38 répondaient aux critères d'exclusion. L'IRA avait été documentée dans 140 (53 %) des cas et plus elle était grave, plus elle était susceptible d'être documentée (stade 1 = 38 %; stade 2 = 51 %; stade 3 = 75 %). Parmi ceux où l'IRA était documentée, 94 (67 %) mentionnaient sa gravité et 116 (83 %) mentionnaient son statut ou sa trajectoire à la sortie du patient. Un plan de suivi avec le praticien était mentionné dans 239 (91 %) des résumés de départ, mais seuls 23 (10 %) mentionnaient un suivi en néphrologie. Les patients dont l'IRA était documentée étaient plus susceptibles de faire l'objet d'un suivi en néphrologie que ceux sans mention de l'IRA (17 % contre 1 %). En ce qui concerne les plans de suivi de laboratoire, 92 (35 %) des résumés contenaient des recommandations. Dans les résumés qui mentionnaient des médicaments normalement maintenus pendant un épisode d'IRA, seule la moitié environ faisait spécifiquement référence à ces médicaments comme ayant été cessés, ajustés ou documentés dans un plan post-sortie. Dans les résumés de départ qui listaient des AINS, 64 % mentionnaient qu'ils avaient été cessés temporairement et 9 % comprenaient un plan au congé de l'hôpital. Dans les résumés de départ qui listaient des IECA/ARA, 38 % mentionnaient que ces médicaments avaient été cessés temporairement et 46 % comprenaient un plan au congé de l'hôpital. Dans les résumés qui listaient des diurétiques, 35 % mentionnaient qu'ils avaient été cessés temporairement et 51 % comprenaient un plan au congé de l'hôpital. Limites et conclusion: Nous avons constaté que la qualité et l'exhaustivité des résumés de départ étaient sous-optimales chez les patients hospitalisés ayant vécu un épisode d'IRA. Cette situation peut contribuer à l'inadéquation du suivi et des soins post-hospitalization pour cette population de patients. Des stratégies sont nécessaires pour accroître la documentation d'un épisode d'IRA dans les résumés de départ et augmenter la qualité de sa communication. Les résultats de cette étude sont notamment limités par notre définition de l'IRA fondée sur des critères de laboratoire qui pourraient avoir manqué des patients répondant aux critères fondés sur la production d'urine. Notre définition de l'IRA fondée sur le taux de créatinine le plus élevée et le plus faible pendant l'admission pourrait également avoir conduit à un surdiagnostic. En outre, sans les résultats de laboratoires externes, il est possible que nous n'ayons pas saisi la mesure initiale réelle de la créatinine chez certains patients.

Kidney Failure Risk Equation in vascular access planning: a population-based study supporting value in decision making.

Background: The Kidney Failure Risk Equation (KFRE) can play a better role in vascular access (VA) planning in patients with chronic kidney disease (CKD) requiring hemodialysis (HD). We described the VA creation and utilization pattern under existing estimated glomerular filtration rate (eGFR)-based referral, and investigated the utility of KFRE score as an adjunct variable in VA planning. Methods: Patients with CKD aged ≥18 years with eGFR <20 mL/min/1.73 m2 who chose HD as dialysis modality from January 2010 to August 2020 were included from a population-based database in British Columbia, Canada. Modality selection date was the index date. Exposures were categorized as (i) current eGFR-based referral, (ii) eGFR-based referral plus KRFE 2-year risk score on index date (KFRE-2) >40% and (iii) eGFR-based referral plus KFRE-2 ≤40%. We estimated the proportion of patients who started HD on arteriovenous fistula/graft (AVF/G) within 2 years, indicating timely pre-emptive creation, and the proportion of patients in whom AVF/G was created but did not start HD within 2 years, indicating too-early creation. Results: Study included 2581 patients, median age 71 years, 60% male. Overall, 1562(61%) started HD and 276 (11%) experienced death before HD initiation within 2 years. Compared with current referral, the proportion of patients who started HD on AVF/G was significantly higher when KFRE-2 was considered in addition to current referral (49% vs 58%, P-value <.001). Adjunct KFRE-2 significantly reduced too-early creation (31% vs 18%, P-value <.001). Conclusions: KFRE in addition to existing eGFR-based referral for VA creation has the potential to improve VA resource utilization by ensuring more patients start HD on AVF/G and may minimize too-early/unnecessary creation. Prospective research is necessary to validate these findings.

The Quality of Discharge Summaries After Acute Kidney Injury.

Background: Acute kidney injury (AKI) increases the risk of hospital readmission, chronic kidney disease, and death. Therefore, effective communication in discharge summaries is essential for safe transitions of care. Objective: The objectives of this study were to determine the quality of discharge summaries in AKI survivors and identify predictors of higher quality discharge summaries. Design: Retrospective chart review. Setting: Tertiary care academic center in Ontario, Canada. Patients: We examined the discharge summary quality of 300 randomly selected adult patients who survived a hospitalization with AKI at our tertiary care hospital, stratified by AKI severity. We included 150 patients each from 2015 to 2016 and 2018 to 2019, before and after introduction of a post-AKI clinic in 2017. Measurements: We reviewed charts for 9 elements of AKI care to create a composite score summarizing discharge summary quality. Methods: We used multivariable logistic regression to identify predictors of discharge summary quality. Results: The median discharge summary composite score was 4/9 (interquartile range, 2-6). The least frequently mentioned elements were baseline creatinine (n = 55, 18%), AKI-specific follow-up labs (n = 66, 22%), and medication recommendations (n = 80, 27%). The odds of having a higher quality discharge summary (composite score ≥4/9) was greater for every increase in baseline creatinine of 25 µmol/L (adjusted odds ratio [aOR]: 1.27; 95% confidence interval [CI]: 1.03, 1.56), intrarenal etiology (aOR: 2.32; 95% CI: 1.26, 4.27), and increased AKI severity (stage 2 aOR: 2.57; 95% CI: 1.35, 4.91 and stage 3 aOR: 3.36; 95% CI: 1.56, 7.22). There was no association between discharge summary quality and the years before and after introduction of a post-AKI clinic (aOR: 0.77; 95% CI: 0.46, 1.29). Limitations: The single-center study design limits generalizability. Conclusions: Most discharge summaries are missing key AKI elements, even in patients with severe AKI. These gaps suggest several opportunities exist to improve discharge summary communication following AKI.

Contexte: L'insuffisance rénale aiguë (IRA) augmente le risque de réadmission à l'hôpital, d'insuffisance rénale chronique et de décès. Une communication efficace est essentielle dans le résumé de départ pour assurer une transition sécuritaire des soins. Objectifs: Cette étude visait à évaluer la qualité des résumés de départ des survivants d'un épisode d'IRA et à identifier les facteurs prédictifs d'un résumé de départ de meilleure qualité. Conception: Examen rétrospectif des dossiers médicaux. Cadre: Un centre universitaire de soins tertiaires d'Ottawa (Ontario) au Canada. Sujets: Nous avons examiné la qualité du résumé de départ de 300 patients adultes ayant survécu à une hospitalisation pour IRA dans notre hôpital de soins tertiaires. Les patients ont été sélectionnés au hasard et stratifiés selon la gravité de l'IRA. Nous avons retenu 150 patients pour la période 2015-2016 et 150 patients pour la période 2018-2019; soit les périodes précédant et suivant l'introduction d'une clinique post-IRA en 2017. Mesures: Nous avons examiné les dossiers médicaux à la recherche de neuf éléments des soins d'IRA afin de créer un score composite évaluant la qualité du résumé de départ. Méthodologie: La régression logistique multivariée a été employée pour identifier les facteurs prédictifs de la qualité d'un résumé de départ. Résultats: Le score composite médian était de 4/9 (intervalle interquartile: 2-6). Les éléments les moins souvent mentionnés dans le résumé de départ étaient le taux de créatinine initial (n= 55; 18 %), les analyses de laboratoires liées spécifiquement au suivi de l'IRA (n= 66; 22 %) et les recommandations portant sur la médication (n= 80; 27 %). Les probabilités d'avoir un résumé de départ de qualité supérieure (score composite ≥4/9) étaient plus élevées pour chaque augmentation de 25 µmol/L de la créatinine initiale (RC corrigé [RCc] = 1,27; IC 95: 1,03-1,56), lorsque l'étiologie était intrarénale (RCc: 2,32; IC 95: 1,26-4,27) et la gravité de l'IRA accrue ([stade 2] RCc: 2,57; IC 95: 1,35-4,91; et [stade 3] RCc: 3,36; IC 95: 1,56-7,22). Aucune association n'a été observée entre la qualité du résumé de départ et la période étudiée, soit avant ou après l'introduction de la clinique post-IRA (RCc: 0,77; IC 95: 0,46-1,29). Limites: L'étude est monocentrique, ce qui limite la généralisabilité des résultats. Conclusion: Certains éléments clés des soins de l'IRA étaient absents de la plupart des résumés de départ, même chez les patients gravement atteints d'IRA. Ces lacunes indiquent qu'il est possible d'améliorer la communication du résumé de départ à la suite d'un épisode d'IRA.

Safety and Effectiveness of Rivaroxaban Versus Warfarin Across GFR Levels in Atrial Fibrillation: A Population-Based Study in Australia and Canada.

Rationale & Objective: The benefit-risk profile of rivaroxaban versus warfarin for atrial fibrillation (AF) in patients with chronic kidney disease is uncertain. We compared rivaroxaban with warfarin across the range of kidney function in adults with AF. Study Design: Multicenter retrospective cohort. Setting & Participants: Adults with AF and a measure of estimated glomerular filtration rate (eGFR); using administrative data from 5 jurisdictions across Australia and Canada (2011-2018). Kidney function was categorized as eGFR ≥60, 45-59, 30-44, and <30 mL/min/1.73 m2. Patients receiving dialysis and kidney transplant recipients were excluded. Exposures: New dispensation of either rivaroxaban or warfarin. Outcomes: Composite (1) effectiveness outcome (all-cause death, ischemic stroke, or transient ischemic attack) and (2) major bleeding events (intracranial, gastrointestinal, or other) at 1 year. Analytical Approach: Cox proportional hazards models accounting for propensity score matching were performed independently in each jurisdiction and then pooled using random-effects meta-analysis. Results: 55,568 patients (27,784 rivaroxaban-warfarin user matched pairs; mean age 74 years, 46% female, 33.5% with eGFR <60 mL/min/1.73 m2) experienced a total of 4,733 (8.5%) effectiveness and 1,144 (2.0%) bleeding events. Compared to warfarin, rivaroxaban was associated with greater or similar effectiveness across a broad range of kidney function (pooled HRs of 0.72 [95% CI, 0.66-0.78], 0.78 [95% CI, 0.58-1.06], 0.70 [95% CI, 0.57-0.87], and 0.78 [95% CI, 0.62-0.99]) for eGFR ≥60, 45-59, 30-44, and <30 mL/min/1.73 m2, respectively). Rivaroxaban was also associated with similar risk of major bleeding across all eGFR categories (pooled HRs of 0.75 [95% CI, 0.56-1.00], 1.01 [95% CI, 0.79-1.30], 0.87 [95% CI, 0.66-1.15], and 0.63 [95% CI, 0.37-1.09], respectively). Limitations: Unmeasured treatment selection bias and residual confounding. Conclusions: In adults with AF, rivaroxaban compared with warfarin was associated with lower or similar risk of all-cause death, ischemic stroke and transient ischemic attack and similar risk of bleeding across a broad range of kidney function. Plain-Language Summary: This real-world study involved a large cohort of 55,568 adults with atrial fibrillation from 5 jurisdictions across Australia and Canada. It showed that the favorable safety (bleeding) and effectiveness (stroke or death) profile of rivaroxaban compared with warfarin was consistent across different levels of kidney function. This study adds important safety data on the use of rivaroxaban in patients with reduced kidney function, including those with estimated glomerular filtration rate <30 mL/min/1.73 m2 in whom the risks and benefits of rivaroxaban use is most uncertain. Overall, the study supports the use of rivaroxaban as a safe and effective alternative to warfarin for atrial fibrillation across differing levels of kidney function.

Long-term effect of COVID-19 infection on kidney function among COVID-19 patients followed in post-COVID-19 recovery clinics in British Columbia, Canada.

BACKGROUND: We investigated the effect of Post-Acute COVID Syndrome or "long-COVID" on kidney function among patients followed in post-COVID recovery clinics (PCRC) in British Columbia, Canada. METHODS: Long-COVID patients referred to PCRC between July 2020 to April 2022, aged ≥18 years who had an estimated glomerular filtration rate (eGFR) value recorded at 3 months from the coronavirus disease 2019 (COVID-19) diagnosis (index) date were included. Those requiring renal replacement therapy prior to index date were excluded. Primary outcome was change in eGFR and urine albumin-creatinine ratio (UACR) after COVID-19 infection. The proportion of patients in each of the six eGFR categories (<30, 30-44, 45-59, 60-89, 90-120 and >120 mL/min/1.73 m2) and three UACR categories (<3, 3-30 and >30 mg/mmol) in all of the study time points were calculated. Linear mixed model was used to investigate change in eGFR over time. RESULTS: The study sample included 2212 long-COVID patients. Median age was 56 years, 51% were male. Half (∼47%-50%) of the study sample had normal eGFR (≥90 mL/min/1.73 m2) from COVID-19 diagnosis to 12 months post-COVID and <5% of patients had an eGFR <30 mL/min/1.73 m2. There was an estimated 2.96 mL/min/1.73 m2 decrease in eGFR within 1 year after COVID-19 infection that was equivalent to 3.39% reduction from the baseline. Decline in eGFR was highest in patients hospitalized for COVID-19 (6.72%) followed by diabetic patients (6.15%). More than 40% of patients were at risk of CKD. CONCLUSIONS: People with long-COVID experienced a substantial decline in eGFR within 1 year from the infection date. The prevalence of proteinuria appeared to be high. Close monitoring of kidney function is prudent among patients with persistent COVID-19 symptoms.

Kidney function and the comparative effectiveness and safety of direct oral anticoagulants vs. warfarin in adults with atrial fibrillation: a multicenter observational study.

AIMS: The aim of this study was to determine the comparative effectiveness and safety of direct oral anticoagulants (DOACs) and warfarin in adults with atrial fibrillation (AF) by level of kidney function. METHODS AND RESULTS: We pooled findings from five retrospective cohorts (2011-18) across Australia and Canada of adults with; a new dispensation for a DOAC or warfarin, an AF diagnosis, and a measure of baseline estimated glomerular filtration rate (eGFR). The outcomes of interest, within 1 year from the cohort entry date, were: (1) the composite of all-cause death, first hospitalization for ischaemic stroke, or transient ischaemic attack (effectiveness), and (2) first hospitalization for major bleeding defined as an intracranial, upper or lower gastrointestinal, or other bleeding (safety). Cox models were used to examine the association of a DOAC vs. warfarin with outcomes, after 1:1 matching via a propensity score. Kidney function was categorized as eGFR ≥60, 45-59, 30-44, and <30 mL/min/1.73 m2. A total of 74 542 patients were included in the matched analysis. DOAC initiation was associated with greater or similar effectiveness compared with warfarin initiation across all eGFR categories [pooled HRs (95% CIs) for eGFR categories: 0.74(0.69-0.79), 0.76(0.54-1.07), 0.68(0.61-0.75) and 0.86(0.76-0.98)], respectively. DOAC initiation was associated with lower or similar risk of major bleeding than warfarin initiation [pooled HRs (95% CIs): 0.75(0.65-0.86), 0.81(0.65-1.01), 0.82(0.66-1.02), and 0.71(0.52-0.99), respectively). Associations between DOAC initiation, compared with warfarin initiation, and study outcomes were not modified by eGFR category. CONCLUSION: DOAC use, compared with warfarin use, was associated with a lower or similar risk of all-cause death, ischaemic stroke, and transient ischaemic attack and also a lower or similar risk of major bleeding across all levels of kidney function.

Prescription Pattern of Cation Exchange Resins and Their Efficacy in Treating Chronic Hyperkalemia Among Patients With Chronic Kidney Diseases: Findings From a Population-Based Analysis in British Columbia, Canada.

Background: Little was known about how chronic hyperkalemia (cHK) in patients with chronic kidney disease (CKD) is managed in British Columbia, Canada. Objective: To investigate the trend in sodium polystyrene sulfonate (SPS) and calcium polystyrene sulfonate (CPS) utilization and their efficacy in treating cHK in CKD patients from British Columbia, Canada. Study Design: Retrospective cohort. Setting & Patients: CKD patients aged ≥18 years, followed in Kidney Care Clinic (KCC), who had at least 2 potassium values ≥5.0 mmol/L separated by no more than 91 days during the period of June 1, 2015, to July 31, 2021, were included. Index date was the first date of the 2 potassium values ≥5.0 mmol/L. Patients who received SPS or CPS within 90 days before index date were excluded. Patients who were on dialysis or received kidney transplantation on or before index date were also excluded. Exposure: Continuous exposure to SPS and CPS. Outcome: SPS/CPS prescription utilization trend was described by the proportion of patients ever treated with SPS/CPS, median time in days between cHK diagnosis and initiating treatment with SPS/CPS, total and median number of SPS/CPS prescriptions dispensed. Change in mean serum potassium concentration before and after a 90-day continuous treatment with SPS/CPS was estimated. Analytical Approach: Descriptive. Results: This study included 10 495 patients with cHK (median age 74 years, 60% were male). Median follow-up time was 625 days. Only 2864 (27%) patients were dispensed at least 1 prescription of either SPS or CPS. A total 7300 prescriptions were dispensed; median prescriptions dispensed per patients were 2 (interquartile range [IQR]: 1-3). Median time from index date to the first prescription dispensing date was 154 days (IQR: 36-455). Continuous 90-day treatment with SPS/CPS decreased the mean serum potassium concentration by 0.60 mmol/L, from 5.58 to 4.98 mmol/L. Limitations: Descriptive observational study without control group. Conclusions: In British Columbia, only 1 in 4 CKD patients with cHK were dispensed with SPS/CPS, mostly with higher degrees of hyperkalemia. These medications appeared to be moderately effective in reducing the serum potassium concentration. Future research is necessary to evaluate the comparative effectiveness of newer generation medications.

Contexte: On savait peu de choses sur la façon dont l'hyperkaliémie chronique (HKc) est prise en charge chez les patients atteints d'insuffisance rénale chronique (IRC) de la Colombie-Britannique (C.-B.), au Canada. Objectif: Étudier les tendances d'utilisation du sulfonate de polystyrène sodique (SPS) et du sulfonate de polystyrène calcique (SPC), ainsi que l'efficacité de ces agents dans le traitement de l'HKc chez les patients britanno-colombiens atteints d'IRC. Type d'étude: étude de cohorte rétrospective. Sujets et cadre de l'étude: Ont été inclus des adultes atteints d'IRC suivis en clinique de soins rénaux qui avaient au moins 2 valeurs de potassium ≥ 5,0 mmol/L mesurées à moins de 91 jours d'intervalle entre le 1er juin 2015 et le 31 juillet 2021. La date de la première des deux valeurs de potassium ≥ 5,0 mmol/L constitue la date indice. Les patients qui avaient reçu du SPS ou du SPC dans les 90 jours précédant la date indice ont été exclus. Les patients sous dialyse ou ayant reçu une greffe rénale avant ou à la date indice ont également été exclus. Exposition: Exposition continue au SPS et au SPC. Résultats: La tendance d'utilisation de SPS/SPC a été décrite par la proportion de patients ayant déjà été traités par SPS/SPC, par le temps médian en jours entre le diagnostic d'hyperkaliémie chronique et le début du traitement par SPS/SPC, et par le nombre total et médian de prescriptions de SPS/SPC délivrées. La variation de la concentration moyenne de potassium sérique avant et après un traitement continu de 90 jours avec SPS/SPC a été estimée. Approche analytique: Descriptive. Résultats: L'étude porte sur 10 495 patients atteints d'hyperkaliémie chronique (60 % d'hommes; âge médian: 74 ans). Le temps médian de suivi était de 625 jours. Seulement 2 864 (27 %) patients avaient reçu au moins une prescription de SPS ou de SPC. Au total, 7 300 ordonnances ont été délivrées; la moyenne d'ordonnances délivrées par patient était de 2 (IIQ: 1, 3). Le délai médian entre la date indice et la date de la première ordonnance était de 154 jours (IIQ: 36, 455). Un traitement continu de 90 jours avec SPS/SPC a abaissé la concentration moyenne de potassium sérique de 0,60 mmol/L, la faisant passer de 5,58 à 4,98 mmol/L. Limites: Étude observationnelle descriptive sans groupe témoin. Conclusion: En C.-B., seul un patient sur quatre atteint d'IRC avec HKc avait reçu une prescription de SPS/SPC, la plupart présentaient des degrés plus élevés d'hyperkaliémie. Ces médicaments se sont avérés modérément efficaces pour réduire la concentration sérique en potassium. Des recherches supplémentaires sont nécessaires pour évaluer l'efficacité comparative des médicaments de nouvelle génération.

Temporal Trends in Hemoglobin, Use of Erythropoiesis Stimulating Agents, and Major Clinical Outcomes in Incident Dialysis Patients in Canada.

INTRODUCTION: Several jurisdictions have adopted a more conservative approach to anemia in patients receiving dialysis amid safety concerns from target hemoglobin studies. It is largely unknown if this has contributed to a change in clinical outcomes. METHODS: A national registry was used to identify 35,945 adult patients who initiated and were maintained on dialysis for ≥90 days in Canada from January 2007 to December 2015. Outcomes were ascertained until March 2017 via linkage with hospital discharge diagnoses. Cox proportional hazards models were used to investigate the association between the era of dialysis initiation and the primary composite outcome (acute myocardial infarction [AMI], stroke, or mortality). RESULTS: The mean hemoglobin at dialysis initiation decreased from 102.9 g/l in 2007 to 95.5 g/l in 2015, corresponding with a higher prevalence of hemoglobin <80 g/l (8% to 17%) and a reduction in erythropoiesis stimulating agent (ESA) use (49% to 44%). After multivariable adjustment, Era 3 (2013-2015) was associated with an 8% relative risk reduction in the primary outcome compared with Era 1 (2007-2009) (hazard ratio [HR] 0.92, 95% confidence interval [CI] 0.88-0.96), a 10% relative reduction in mortality (HR 0.90, 95% CI 0.85-0.94) but no significant change in AMI or stroke. In a model without era, neither hemoglobin nor ESA use was an independent predictor of outcome. CONCLUSION: There have been modest declines in average hemoglobin values and ESA use among incident dialysis patients in Canada with no change in major cardiovascular outcomes. Patient survival has improved over time, likely for reasons other than anemia management.