Public and patient perspectives on the use of clinical and administrative health data to identify and contact people at risk of future illness-The case of chronic kidney disease.

For decades, researchers have used linkable administrative health data for evaluating the health care system, subject to local privacy legislation. In Ontario, Canada, the relevant privacy legislation permits some organizations (prescribed entities) to conduct this kind of research but is silent on their ability to identify and contact individuals in those datasets. Following consultation with the Office of the Information and Privacy Commissioner of Ontario, we developed a pilot study to identify and contact by mail a sample of people at high risk for kidney failure within the next 2 years, based on laboratory and administrative data from provincial datasets held by ICES, to ensure they receive needed kidney care. Before proceeding, we conducted six focus groups to understand the acceptability to the public and people living with chronic kidney disease of direct mail outreach to people at high risk of developing kidney failure. While virtually all participants indicated they would likely participate in the study, most felt strongly that the message should come directly from their primary care provider or whoever ordered the laboratory tests, rather than from an unknown organization. If this is not possible, they felt the health care provider should be made aware of the concern related to their kidney health. Most agreed that, if health authorities could identify people at high risk of a treatable life-threatening illness if caught early enough, there is a social responsibility to notify people. While privacy laws allow for free flow of health information among health care providers who provide direct clinical care, the proposed case-finding and outreach falls outside that model. Enabling this kind of information flow will require greater clarity in existing laws or revisions to these laws. This also requires adequate notification and culture change for health care providers and the public around information uses and flows.

Mental health and addiction service utilization among people living with chronic kidney disease.

BACKGROUND: Mental health problems, particularly anxiety and depression, are common in patients with chronic kidney disease (CKD), and negatively impact quality of life, treatment adherence, and mortality. However, the degree to which mental health and addictions services are utilized by those with CKD is unknown. We examined the history of mental health and addictions service use of individuals across levels of kidney function. METHODS: We performed a population-based cross-sectional study using linked healthcare databases from Ontario, Canada from 2009 to 2017. We abstracted the prevalence of individuals with mental health and addictions service use within the previous 3 years across levels of kidney function (eGFR$\ \ge $60, 45 to < 60, 30 to < 45, 15 to < 30, <15 mL/min per 1.73m2 and maintenance dialysis). We calculated prevalence ratios (PR) to compare prevalence across kidney function strata, while adjusting for age, sex, year of cohort entry, urban versus rural location, area-level marginalization, and Charlson comorbidity scores. RESULTS: Of 5 956 589 adults, 9% (n = 534 605) had an eGFR<60 mL/min per 1.73m2 or were receiving maintenance dialysis. Fewer individuals with eGFR < 60 had a history of any mental health and addictions service utilization (crude prevalence range 28% to 31%), compared to individuals with eGFR ≥ 60 (35%). Compared to eGFR ≥ 60, the lowest prevalence of individuals with any mental health and addictions service utilization was among those with eGFR 15 to < 30 (adjusted PR 0.86, 95% CI 0.85 to 0.88), eGFR < 15 (adjusted PR 0.81, 95% CI 0.76 to 0.86) and those receiving maintenance dialysis (adjusted PR 0.83, 95% CI 0.81 to 0.84). Less use of outpatient services accounted for differences in service utilization. CONCLUSIONS: Mental health and addictions service utilization is common but less so in individuals with advanced CKD in Ontario, Canada.

Patient Care Gaps Prior to Maintenance Dialysis Initiation: A Population-Based Retrospective Study.

Background: Guidelines in Ontario, Canada, recommend timely referral for multidisciplinary kidney care to facilitate planned dialysis initiation. Many patients do not receive recommended multidisciplinary kidney care prior to dialysis. Objective: To better understand why this gap in pre-dialysis care exists, we conducted a study to describe the pathways by which patients initiate maintenance dialysis. Design: A retrospective cohort study. Setting: Population-based, using health care administrative databases from Ontario, Canada. Patients: Adults initiating maintenance dialysis from April 2016 to March 2019. Measurements and methods: Patients were grouped based on whether they received recommended multidisciplinary kidney care prior to dialysis initiation (at least 1 year of care with at least 2 visits). For those who did not receive recommended care, we grouped patients as having no identified care gap or into the following groups: (1) lack of timely chronic kidney disease (CKD) screening, (2) late nephrology referral (<1 year), or (3) late or no referral for multidisciplinary kidney care among patients followed by a nephrologist for at least 1 year. Results: A total of 9216 patients were included with a mean (standard deviation) age of 66 (15) years, and 61.5% were male. Of the total, 896 (9.7%) patients died, 7671 (83.2%) remained on dialysis at 90 days, and 649 (7.0%) had stopped dialysis due to kidney function recovery within 90 days. Of the 9216 patients, 5434 (59%) had not received recommended multidisciplinary kidney care. Among those without recommended care, there were 2251 (41.4%) patients with no identified care gaps, 1351 (24.9%) patients with a lack of timely CKD screening, 359 (6.6%) patients with late nephrology referral, and 1473 (27.1%) patients with late or no referral for multidisciplinary kidney care. Limitations: We could not determine if patients were referred but declined multidisciplinary kidney care. Conclusions: More than half of patients had not received recommended multidisciplinary kidney care. Many patients experienced an acute decline in kidney function, which may not be preventable, but in others, there were missed opportunities for CKD screening or early referral to nephrology, or at the level of nephrology practice for early referral for multidisciplinary care. This work could be used to inform policies aimed at improving increased uptake of multidisciplinary kidney care prior to dialysis.

Contexte: Les lignes directrices de l'Ontario (Canada) recommandent que les patients soient dirigés en temps opportun vers une prise en charge multidisciplinaire de la maladie rénale afin de faciliter l'initiation planifiée de la dialyze. Cette recommandation n'est toutefois pas appliquée pour de nombreux patients. Objectif: Afin de mieux comprendre ce qui explique cette lacune dans les soins de prédialyse, nous avons menu une étude visant à décrire le parcours des patients jusqu'à l'initiation de la dialyse chronique. Conception: Étude de cohorte rétrospective. Cadre: Étude populationnelle réalisée à partir des bases de données administratives de santé de l'Ontario (Canada). Sujets: Adultes ayant amorcé une dialyse d'entretien entre avril 2016 et mars 2019. Méthodologie et mesures: Les patients ont été groupés selon qu'ils avaient ou non reçu des soins multidisciplinaires recommandés avant l'initiation de la dialyse (au moins un an de soins incluant au moins deux visites). Les patients qui n'avaient pas reçu les soins recommandés ont été groupés soit comme ne présentant aucune lacune de soins identifiée, soit dans l'un des groupes suivants: i) absence de dépistage de l'IRC en temps opportun; ii) référence tardive en néphrologie (<1 an); iii) patients suivis depuis au moins un an par un néphrologue et non référés vers des soins multidisciplinaires ou référés tardivement. Résultats: En tout, 9 216 patients (61,5 % d'hommes) âgés en moyenne de 66 ans (écart-type: 15 ans) ont été inclus. De cette cohorte, 896 (9,7 %) patients sont décédés, 7 671 (83,2 %) étaient toujours sous dialyse après 90 jours et 649 (7,0 %) avaient cessé la dialyse dans les 90 jours en raison de la récupération de la fonction rénale. Le nombre total de patients n'ayant pas reçu les soins multidisciplinaires recommandés s'élevait à 5 434 (59 %). De ce nombre, 2 251 patients (41,4 %) ont été classés sans lacune de soins identifiée, 1 351 patients (24,9 %) n'avaient pas bénéficié d'un dépistage précoce de l'IRC, 359 patients (6,6 %) avaient été référés tardivement en néphrologie, et 1 473 patients (27,1 %) n'avaient pas été référés en soins multidisciplinaires ou l'avaient été tardivement. Limites: Nous n'avons pas été en mesure de déterminer si certains patients référés vers des soins multidisciplinaires avaient refusé ces soins. Conclusion: Plus de la moitié des patients n'ont pas reçu les soins multidisciplinaires recommandés avant la dialyse. De nombreux patients ont vécu une baisse rapide de leur fonction rénale, qui n'aurait possiblement pas pu être évitée, mais dans d'autres cas, des occasions de dépistage précoce de l'IRC ou de référence précoce en néphrologie ont été manquées. Au niveau de la pratique en néphrologie, là encore, des occasions de référence précoce vers des soins multidisciplinaires ont pu être manquées. Ces travaux pourraient éclairer les politiques visant à améliorer la prise en charge multidisciplinaire de la maladie rénale avant la dialyse.

Hypocalcemia Risk of Denosumab Across the Spectrum of Kidney Disease: A Population-Based Cohort Study.

Denosumab can be used in patients with chronic kidney disease (CKD) but has been linked with cases of severe hypocalcemia. The incidence of and risk factors for hypocalcemia after denosumab use are not well established. Using linked health care databases at ICES, we conducted a population-based cohort study of adults >65 years old with a new prescription for denosumab or a bisphosphonate between 2012 and 2020. We assessed incidence of hypocalcemia within 180 days of drug dispensing and stratified results by estimated glomerular filtration rate (eGFR in mL/min/1.73 m2 ). We used Cox proportional hazards to assess risk factors for hypocalcemia. There were 59,151 and 56,847 new denosumab and oral bisphosphonate users, respectively. Of the denosumab users, 29% had serum calcium measured in the year before their prescription, and one-third had their serum calcium checked within 180 days after their prescription. Mild hypocalcemia (albumin corrected calcium <2.00 mmol/L) occurred in 0.6% (95% confidence interval [CI] 0.6, 0.7) of new denosumab users and severe hypocalcemia (<1.8 mmol/L) in 0.2% (95% CI 0.2, 0.3). In those with an eGFR <15 or receiving maintenance dialysis, the incidence of mild and severe hypocalcemia was 24.1% (95% CI 18.1, 30.7) and 14.9% (95% CI 10.1, 20.7), respectively. In this group, kidney function and baseline serum calcium were strong predictors of hypocalcemia. We did not have information on over-the-counter vitamin D or calcium supplementation. In new bisphosphonate users, the incidence of mild hypocalcemia was 0.3% (95% CI 0.3, 0.3) with an incidence of 4.7% (95% CI 1.5, 10.8) in those with an eGFR <15 or receiving maintenance dialysis. In this large population-based cohort, we found that the overall risk of hypocalcemia with new denosumab use was low but increased substantially in those with eGFR <15 mL/min/1.73 m2 . Future studies should investigate strategies to mitigate hypocalcemia. © 2023 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Perceptions of Artificial Intelligence Use in Primary Care: A Qualitative Study with Providers and Staff of Ontario Community Health Centres.

PURPOSE: To understand staff and health care providers' views on potential use of artificial intelligence (AI)-driven tools to help care for patients within a primary care setting. METHODS: We conducted a qualitative descriptive study using individual semistructured interviews. As part of province-wide Learning Health Organization, Community Health Centres (CHCs) are a community-governed, team-based delivery model providing primary care for people who experience marginalization in Ontario, Canada. CHC health care providers and staff were invited to participate. Interviews were audio-recorded and transcribed verbatim. We performed a thematic analysis using a team approach. RESULTS: We interviewed 27 participants across 6 CHCs. Participants lacked in-depth knowledge about AI. Trust was essential to acceptance of AI; people need to be receptive to using AI and feel confident that the information is accurate. We identified internal influences of AI acceptance, including ease of use and complementing clinical judgment rather than replacing it. External influences included privacy, liability, and financial considerations. Participants felt AI could improve patient care and help prevent burnout for providers; however, there were concerns about the impact on the patient-provider relationship. CONCLUSIONS: The information gained in this study can be used for future research, development, and integration of AI technology.

The Alliance for Healthier Communities' journey to a learning health system in primary care.

Introduction: The Alliance for Healthier Communities represents community-governed healthcare organizations in Ontario, Canada including Community Health Centres, which provide primary care to more disadvantaged populations. Methods: In this experience report, we describe the Alliance's journey towards becoming a learning health system using examples for organizational culture, data and analytics, people and partnerships, client engagement, ethics and oversight, evaluation and dissemination, resources, identification and prioritization, and deliverables and impact. Results: Many of the foundational elements for a learning health system were already in place at the Alliance including an integrated and accessible data platform. Leadership championed and embraced the movement towards a learning health system, which led to restructuring of the organization. This included role changes for data support personnel, better communication, and dissemination plans, strategies to engage clinicians and other front-line staff, restructuring of committees for more collaborative planning and prioritization of quality improvement and research initiatives, and the development of a new Practice-Based Learning Network for more opportunities to use the data for research and evaluation. Conclusions: Next steps will focus on continued clinical engagement and partnerships as well as ongoing reflection on the transition and success of the learning health system work.

Long-term Health Care Utilization and Associated Costs After Dialysis-Treated Acute Kidney Injury in Children.

RATIONALE & OBJECTIVE: Acute kidney injury (AKI) is common among hospitalized children and is associated with increased hospital length of stay and costs. However, there are limited data on postdischarge health care utilization after AKI hospitalization. Our objectives were to evaluate health care utilization and physician follow-up patterns after dialysis-treated AKI in a pediatric population. STUDY DESIGN: Retrospective cohort study, using provincial health administrative databases. SETTING & PARTICIPANTS: All children (0-18 years) hospitalized between 1996 and 2017 in Ontario, Canada. Excluded individuals comprised non-Ontario residents; those with metabolic disorders or poisoning; and those who received dialysis or kidney transplant before admission, a kidney transplant by 104 days after discharge, or were receiving dialysis 76-104 days from dialysis start date. EXPOSURE: Episodes of dialysis-treated AKI, identified using validated health administrative codes. AKI survivors were matched to 4 hospitalized controls without dialysis-treated AKI by age, sex, and admission year. OUTCOME: Our primary outcome was postdischarge hospitalizations, emergency department visits, and outpatient physician visits. Secondary outcomes included outpatient visits by physician type and composite health care costs. ANALYTICAL APPROACH: Proportions with≥1 event and rates (per 1,000 person-years). Total and median composite health care costs. Adjusted rate ratios using negative binomial regression models. RESULTS: We included 1,688 pediatric dialysis-treated AKI survivors and 6,752 matched controls. Dialysis-treated AKI survivors had higher rehospitalization and emergency department visit rates during the analyzed follow-up periods (0-1, 0-5, and 0-10 years postdischarge, and throughout follow-up), and higher outpatient visit rates in the 0-1-year follow-up period. The overall adjusted rate ratio for rehospitalization was 1.46 (95% CI, 1.25-1.69; P<0.0001) and for outpatient visits was 1.16 (95% CI, 1.09-1.23; P=0.01). Dialysis-treated AKI survivors also had higher health care costs. Nephrologist follow-up was infrequent among dialysis-treated AKI survivors (18.6% by 1 year postdischarge). LIMITATIONS: Potential miscoding of study exposures or outcomes. Residual uncontrolled confounding. Data for health care costs and emergency department visits was unavailable before 2006 and 2001, respectively. CONCLUSIONS: Dialysis-treated AKI survivors had greater postdischarge health care utilization and costs versus hospitalized controls. Strategies are needed to improve follow-up care for children after dialysis-treated AKI to prevent long-term complications.

The Alliance for Healthier Communities as a Learning Health System for primary care: A qualitative analysis in Ontario, Canada.

RATIONALE, AIMS AND OBJECTIVES: A learning health system model can be used to efficiently evaluate and incorporate evidence-based care into practice. However, there is a paucity of evidence describing key organizational attributes needed to ensure a successful learning health system within primary care. We interviewed stakeholders for a primary care learning health system in Ontario, Canada (the Alliance for Healthier Communities) to identify strengths and areas for improvement. METHOD: We conducted a qualitative descriptive study using individual semistructured interviews with Alliance stakeholders between December 2019 and March 2020. The Alliance delivers community-governed primary healthcare through 109 organizations including Community Health Centres (CHCs). All CHC staff within the Alliance were invited to participate. Interviews were audio-recorded and transcribed verbatim. We performed a thematic analysis using a team approach. RESULTS: We interviewed 29 participants across six CHCs, including Executive Directors, managers, healthcare providers and data support staff. We observed three foundational elements necessary for a successful learning health system within primary care: shared organizational goals and culture, data quality and resources. Building on this foundation, people are needed to drive the learning health system, and this is conditional on their level of engagement. The main factors motivating staff member's engagement with the learning health system included their drive to help improve patient care, focusing on initiatives of personal interest and understanding the purpose of different initiatives. Areas for improvement were identified such as the ability to extract and use data to inform changes in real-time, better engagement and protected time for providers to do improvement work, and more staff dedicated to data extraction and analysis. CONCLUSIONS: We identified key components needed to establish a learning health system in primary care. Similar primary care organizations in Canada and elsewhere can use these insights to guide their development as learning health systems.

Opioid prescribing practices in chronic kidney disease: a population-based cohort study.

BACKGROUND: Chronic pain is common, and its management is complex in patients with chronic kidney disease (CKD), but limited data are available on opioid prescribing. We examined opioid prescribing for non-cancer and non-end-of-life care in patients with CKD. METHODS: This was a population-based retrospective cohort study using administrative databases in Ontario, Canada which included adults with CKD defined by an estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2 from 1 November 2012 to 31 December 2018 and estimated the proportion of opioid prescriptions (type, duration, dose, potentially inappropriate prescribing, etc.) within 1 year of cohort entry. Prescriptions had to precede dialysis, kidney transplant or death. RESULTS: We included 680 445 adults with CKD, and 198 063 (29.1%) were prescribed opioids. Codeine (14.9%) and hydromorphone (7.2%) were the most common opioids. Among opioid users, 24.3% had repeated or long-term use, 26.1% were prescribed high doses and 56.8% were new users. Opioid users were more likely to be female, had cardiac disease or a mental health diagnosis, and had more healthcare visits. The proportions for potentially inappropriate prescribing indicators varied (e.g. 50.1% with eGFR <30 were prescribed codeine, and 20.6% of opioid users were concurrently prescribed benzodiazepines, while 7.2% with eGFR <30 mL/min/1.73 m2 were prescribed morphine, and 7.0% were received more than one opioid concurrently). Opioid prescriptions declined with time (2013 cohort: 31.1% versus 2018 cohort: 24.5%; p <0.0001), as did indicators of potentially inappropriate prescribing. CONCLUSIONS: Opioid use was common in patients with CKD. While opioid prescriptions and potentially inappropriate prescribing have declined in recent years, interventions to improve pain management without the use of opioids and education on safer prescribing practices are needed.

Printed educational materials directed at Ontario family physicians do not improve adherence to guideline recommendations for diabetes management: a pragmatic, factorial, cluster randomized controlled trial [ISRCTN72772651].

BACKGROUND: Printed educational materials (PEMs) have long been used to inform clinicians on evidence-based practices. However, the evidence for their effects on patient care and outcomes is unclear. In Ontario, despite widely available clinical practice guidelines recommending antihypertensives and cholesterol-lowering agents for patients with diabetes, prescriptions remain low. We aimed to determine whether PEMs can influence physicians to intensify prescribing of these medications. METHODS: A pragmatic, 2 × 2 factorial, cluster randomized controlled trial was designed to ascertain the effect of two PEM formats on physician prescribing: a postcard-sized message ("outsert") or a longer narrative article ("insert"). Ontario family physician practices (clusters) were randomly allocated to receive the insert, outsert, both or neither. Physicians were eligible if they were in active practice and their patients were included if they were over 65 years with a diabetes diagnosis; both were unaware of the trial. Administrative databases at ICES (formerly the Institute for Clinical Evaluative Sciences) were used to link patients to their physician and to analyse prescribing patterns at baseline and 1 year following PEM mailout. The primary outcome was intensification defined as the addition of a new antihypertensive or cholesterol-lowering agent, or dose increase of a current drug, measured at the patient level. Analyses were by intention-to-treat and accounted for the clustering of patients to physicians. RESULTS: We randomly assigned 4231 practices (39% of Ontario family physicians) with a total population of 185,526 patients (20% of patients with diabetes in Ontario primary care) to receive the insert, outsert, both, and neither; among these, 4118 practices were analysed (n = 1025, n = 1037, n = 1031, n = 1025, respectively). No significant treatment effect was found for the outsert (odds ratio (OR) 1.01, 95% confidence interval (CI) 0.98 to 1.04) or the insert (OR 0.99, 95% CI 0.96 to 1.02). Percent of intensification in the four arms was similar (approximately 46%). Adjustment for physician characteristics (e.g., age, sex, practice location) had no impact on these findings. CONCLUSIONS: PEMs have no effect on physician's adherence to recommendations for the management of diabetes-related complications in Ontario. Further research should investigate the effect of other strategies to narrow this evidence-to-practice gap. TRIAL REGISTRATION: ISRCTN72772651 . Retrospectively registered 21 July 2005.

Learning health systems in primary care: a systematic scoping review.

BACKGROUND: Learning health systems have been gaining traction over the past decade. The purpose of this study was to understand the spread of learning health systems in primary care, including where they have been implemented, how they are operating, and potential challenges and solutions. METHODS: We completed a scoping review by systematically searching OVID Medline®, Embase®, IEEE Xplore®, and reviewing specific journals from 2007 to 2020. We also completed a Google search to identify gray literature. RESULTS: We reviewed 1924 articles through our database search and 51 articles from other sources, from which we identified 21 unique learning health systems based on 62 data sources. Only one of these learning health systems was implemented exclusively in a primary care setting, where all others were integrated health systems or networks that also included other care settings. Eighteen of the 21 were in the United States. Examples of how these learning health systems were being used included real-time clinical surveillance, quality improvement initiatives, pragmatic trials at the point of care, and decision support. Many challenges and potential solutions were identified regarding data, sustainability, promoting a learning culture, prioritization processes, involvement of community, and balancing quality improvement versus research. CONCLUSIONS: We identified 21 learning health systems, which all appear at an early stage of development, and only one was primary care only. We summarized and provided examples of integrated health systems and data networks that can be considered early models in the growing global movement to advance learning health systems in primary care.

Long-Term Kidney Outcomes Following Dialysis-Treated Childhood Acute Kidney Injury: A Population-Based Cohort Study.

BACKGROUND: AKI is common during pediatric hospitalizations and associated with adverse short-term outcomes. However, long-term outcomes among survivors of pediatric AKI who received dialysis remain uncertain. METHODS: To determine the long-term risk of kidney failure (defined as receipt of chronic dialysis or kidney transplant) or death over a 22-year period for pediatric survivors of dialysis-treated AKI, we used province-wide health administrative databases to perform a retrospective cohort study of all neonates and children (aged 0-18 years) hospitalized in Ontario, Canada, from April 1, 1996, to March 31, 2017, who survived a dialysis-treated AKI episode. Each AKI survivor was matched to four hospitalized pediatric comparators without dialysis-treated AKI, on the basis of age, sex, and admission year. We reported the incidence of each outcome and performed Cox proportional hazards regression analyses, adjusting for relevant covariates. RESULTS: We identified 1688 pediatric dialysis-treated AKI survivors (median age 5 years) and 6752 matched comparators. Among AKI survivors, 53.7% underwent mechanical ventilation and 33.6% had cardiac surgery. During a median 9.6-year follow-up, AKI survivors were at significantly increased risk of a composite outcome of kidney failure or death versus comparators. Death occurred in 113 (6.7%) AKI survivors, 44 (2.6%) developed kidney failure, 174 (12.1%) developed hypertension, 213 (13.1%) developed CKD, and 237 (14.0%) had subsequent AKI. AKI survivors had significantly higher risks of developing CKD and hypertension versus comparators. Risks were greatest in the first year after discharge and gradually decreased over time. CONCLUSIONS: Survivors of pediatric dialysis-treated AKI are at higher long-term risks of kidney failure, death, CKD, and hypertension, compared with a matched hospitalized cohort.

Risk of Hospital Encounters With Kidney Stones in Autosomal Dominant Polycystic Kidney Disease: A Cohort Study.

BACKGROUND: There is a perception that patients with autosomal dominant polycystic kidney disease (ADPKD) are more likely to develop kidney stones than the general population. OBJECTIVE: To compare the rate of hospital encounter with kidney stones and the rate of stone interventions between patients with and without ADPKD. DESIGN: Retrospective cohort study. SETTING: Ontario, Canada. PATIENTS: Patients with and without ADPKD who had a prior hospital encounter between 2002 and 2016. MEASUREMENTS: Rate of hospital encounter with kidney stones and rate of stone intervention. METHODS: We used inverse probability exposure weighting based on propensity scores to balance baseline indicators of health between patients with and without ADPKD. We followed each patient until death, emigration, outcomes, or March 31, 2017. We used a Cox proportional hazards model to compare event rates between the two groups. RESULTS: Patients with ADPKD were at higher risk of hospital encounter with stones compared with patients without ADPKD (81 patients of 2094 with ADPKD [3.8%] vs 60 patients of 1902 without ADPKD [3.2%]; 8.9 vs 5.1 events per 1000 person-years; hazard ratio 1.6 [95% CI, 1.3-2.1]). ADPKD was not associated with a higher risk of stone intervention (49 of 2094 [2.3%] vs 47 of 1902 [2.4%]; 5.3 vs 3.9 events per 1000 person-years; hazard ratio 1.2 [95% CI = 0.9-1.3]). LIMITATIONS: We did not have information on kidney stone events outside of the hospital. There is a possibility of residual confounding. CONCLUSION: ADPKD was a significant risk factor for hospital encounters with kidney stones.

CONTEXTE: Il existe une perception selon laquelle les patients atteints de polykystose rénale autosomique dominante (ADPKD) seraient plus susceptibles de développer des calculs rénaux que la population générale. OBJECTIF: Comparer les taux d'hospitalisations et d'interventions pour calculs rénaux entre des patients atteints ou non d'ADPKD. TYPE D'ÉTUDE: Étude de cohorte rétrospective. CADRE: Ontario, Canada. SUJETS: Des patients atteints ou non d'ADPKD qui avaient déjà été hospitalisés entre 2002 et 2016. MESURES: Les taux d'hospitalisations et d'interventions pour calculs rénaux. MÉTHODOLOGIE: Nous avons utilisé une pondération d'exposition à probabilité inverse fondée sur les scores de propension afin d'équilibrer les indicateurs de santé de base entre les patients atteints ou non d'ADPKD. Nous avons suivi chaque patient jusqu'à son décès, jusqu'à son émigration, jusqu'au résultat ou jusqu'au 31 mars 2017. Nous avons utilisé un modèle de risques proportionnels de Cox pour comparer les taux d'événements entre les deux groupes. RÉSULTATS: Les patients atteints d'ADPKD présentaient un risque plus élevé d'être hospitalisés pour calculs rénaux que les patients non atteints d'ADPKD (81 patients sur 2094 atteints d'ADPKD [3,8 %] contre 60 patients sur 1902 sans ADPKD [3,2 %]; 8,9 contre 5,1 événements pour 1 000 années-personnes; risque relatif: 1,6 [IC 95 %: 1,3 à 2,1]). L'ADPKD n'a pas été associée à un risque plus élevé d'interventions pour retirer des calculs rénaux (49 patients sur 2094 atteints d'ADPKD [2,3 %] contre 47 patients sur 1902 sans ADPKD [2,4 %]; 5,3 contre 3,9 événements pour 1 000 années-personnes; risque relatif: 1,2 [IC 95 %: 0,9 à 1,3]). LIMITES: Nous n'avions pas d'information sur les événements liés aux calculs rénaux à l'extérieur de l'hôpital. Il existe une possibilité de facteurs de confusion résiduels. CONCLUSION: L'ADPKD s'est avéré un facteur de risque important d'être hospitalisé pour des calculs rénaux.

Diagnostic accuracy of administrative codes for autosomal dominant polycystic kidney disease in clinic patients with cystic kidney disease.

BACKGROUND: The ability to identify patients with autosomal dominant polycystic kidney disease (ADPKD) and distinguish them from patients with similar conditions in healthcare administrative databases is uncertain. We aimed to measure the sensitivity and specificity of different ADPKD administrative coding algorithms in a clinic population with non-ADPKD and ADPKD kidney cystic disease. METHODS: We used a dataset of all patients who attended a hereditary kidney disease clinic in Toronto, Ontario, Canada between 1 January 2010 and 23 December 2014. This dataset included patients who met our reference standard definition of ADPKD or other cystic kidney disease. We linked this dataset to healthcare databases in Ontario. We developed eight algorithms to identify ADPKD using the International Classification of Diseases, 10th Revision (ICD-10) codes and provincial diagnostic billing codes. A patient was considered algorithm positive if any one of the codes in the algorithm appeared at least once between 1 April 2002 and 31 March 2015. RESULTS: The ICD-10 coding algorithm had a sensitivity of 33.7% [95% confidence interval (CI) 30.0-37.7] and a specificity of 86.2% (95% CI 75.7-92.5) for the identification of ADPKD. The provincial diagnostic billing code had a sensitivity of 91.1% (95% CI 88.5-93.1) and a specificity of 10.8% (95% CI 5.3-20.6). CONCLUSIONS: ICD-10 coding may be useful to identify patients with a high chance of having ADPKD but fail to identify many patients with ADPKD. Provincial diagnosis billing codes identified most patients with ADPKD and also with other types of cystic kidney disease.

Opportunities To Improve Diabetes Care in the Hemodialysis Unit: A Cohort Study in Ontario, Canada.

Background: Patients with diabetes receiving chronic, in-center hemodialysis face healthcare challenges. We examined the prevalence of gaps in their diabetes care, explored regional differences, and determined predictors of care gaps. Methods: We conducted a population-based, retrospective study between January 1, 2016 and January 1, 2018 in Ontario, Canada. We included adults with prevalent diabetes mellitus receiving in-center hemodialysis as of January 1, 2018 and examined the proportion with (1) insufficient or excessive glycemic monitoring, (2) suboptimal screening for diabetes-related complications (retinopathy and cardiovascular screening), (3) hospital encounters for hypo- or hyperglycemia, and (4) hospital encounters for hypertension in the 2 years prior (January 1, 2016 to January 1, 2018). We then identified patient, provider, and health-system factors associated with more than one care gap and used multivariable logistic regression to determine predictors. Further, we used geographic information systems to explore spatial variation in gaps. Results: There were 4173 patients with diabetes receiving in-center hemodialysis; the mean age was 67 years, 39% were women, and the majority were of lower socioeconomic status. Approximately 42% of patients had more than one diabetes care gap, the most common being suboptimal retinopathy screening (53%). Significant predictors of more than one gap included younger age, female sex, shorter duration of diabetes, dementia, fewer specialist visits, and not seeing a physician for diabetes. There was evidence of spatial variation in care gaps across our region. Conclusions: There are opportunities to improve diabetes care in patients receiving in-center hemodialysis, particularly screening for retinopathy. Focused efforts to bring diabetes support to high-risk individuals might improve their care and outcomes.

Short-and long-term outcomes of sustained low efficiency dialysis vs continuous renal replacement therapy in critically ill patients with acute kidney injury.

BACKGROUND: Sustained low efficiency dialysis (SLED) has emerged as an alternative to continuous renal replacement therapy (CRRT) for the treatment of acute kidney injury (AKI) in critically ill patients. However, there is limited information on the short- and long-term outcomes of SLED compared to CRRT. METHODS: We conducted a retrospective cohort study of patients with AKI who commenced either SLED or CRRT in ICUs at a tertiary care hospital in Toronto, Canada. The primary outcome was 90-day all-cause mortality. Secondary outcomes included mortality at one year, and dialysis dependence at 90 days and one year. All outcomes were ascertained by linkage to provincial datasets. RESULTS: We identified 284 patients, of whom 95 and 189 commenced SLED and CRRT, respectively. Compared to SLED recipients, more CRRT recipients were mechanically ventilated (96% vs 86%, p = 0.002) and receiving vasopressors (94% vs 84%, p = 0.01) at the time of RRT initiation. At 90 days following RRT initiation, 52 (55%) and 126 (67%) SLED and CRRT recipients, respectively, died (adjusted risk ratio (RR) 0.91, 95% CI 0.75-1.11). There was no inter-modality difference in time to death through 90 days (adjusted hazard ratio 0.90, 95% CI 0.64-1.27). Among patients surviving to Day 90, a higher proportion of SLED recipients remained RRT dependent (10 (23%) vs 6 (10%) CRRT recipients, adjusted RR 2.82, 95% CI 1.02-7.81). At one year, there was no difference in mortality or dialysis dependence. CONCLUSIONS: Among critically ill patients with acute kidney injury, mortality at 90 days and one year was not different among patients initiating SLED as compared to CRRT.

Complications in Patients With Autosomal Dominant Polycystic Kidney Disease Undergoing Ureteroscopy: A Cohort Study.

BACKGROUND: Ureteroscopy is a minimally invasive treatment option for upper tract stones. The distorted kidney anatomy in patients with autosomal dominant polycystic kidney disease (ADPKD) may place them at higher risk for ureteroscopic complications. OBJECTIVE: To compare the 30-day risk of ureteroscopic complications between patients with and without ADPKD. DESIGN: Retrospective cohort study. SETTING: Ontario, Canada. PATIENTS: Seventy three patients with ADPKD and 81 445 patients without ADPKD who underwent ureteroscopy for upper urinary tract stones between April 1, 2002, and March 1, 2018. MEASUREMENTS: A 30-day risk of (1) hospital presentation with ureteroscopic complications (which was a composite outcome of either emergency department visit or hospital admission with acute kidney injury, urinary tract infection, or sepsis); (2) all-cause hospital presentation; (3) all-cause hospital admission; and (4) all-cause emergency department visit. METHODS: We regressed outcomes on demographic variables, health care use in the prior 1-year, various procedures and comorbidities related to the outcome in the prior 5 years, and prescribed medications filled in the past 120 days using modified Poisson regression to compare the risk ratio (RR) of each outcome between patients with and without ADPKD. RESULTS: The median (interquartile, IQR) age was 44 (38-60 years) in the ADPKD group and 53 (42-64) in the control group. About 40% were women in both groups. The risk of ureteroscopic complications was not significantly different in patients with versus without ADPKD (8.2% vs 4.3%; adjusted RR = 1.5, 95% confidence interval [CI] = 0.7-3.2). Patients with versus without ADPKD were more likely to present to hospital after their procedure (35.6% vs. 20.0%; adjusted RR = 1.6, 95% CI = 1.2-2.2), which included a statistically significant increase in the risk of presenting to the emergency department (32.9% vs. 19.0%; adjusted RR = 1.6, 95% CI = 1.1-2.2) but not hospital admissions (10.9% vs. 5.0%; adjusted RR = 1.8, 95% CI = 0.9-3.4). LIMITATIONS: The low numbers of events led to imprecision around the estimates. CONCLUSION: Patients with ADPKD have a higher risk of return to the hospital within 30 days of ureteroscopy for stone disease. TRIAL REGISTRATION: We did not register this study.

CONTEXTE: L'urétéroscopie est une option minimalement invasive pour traiter les calculs des voies urinaires hautes. Cependant, les distorsions anatomiques des reins présentes chez les patients atteints de polykystose rénale autosomique dominante (ADPKD) exposent ces derniers à un risque accru de complications liées à la procédure. OBJECTIF: Comparer le risque de complications liées à l'urétéroscopie chez des patients atteints ou non d'ADPKD dans les 30 jours suivant la procédure. TYPE D'ÉTUDE: Étude de cohorte rétrospective. CADRE: Ontario, Canada. SUJETS: L'étude porte sur 73 patients atteints d'ADPKD et 81 445 patients témoins ayant subi une urétéroscopie entre le 1er avril 2002 et le 1er mars 2018 pour le traitement de calculs des voies urinaires hautes. MESURES: Le risque dans les 30 jours de: 1) visite à l'hôpital pour des complications liées à l'urétéroscopie (résultat composite d'une visite aux urgences ou d'une admission en raison d'une insuffisance rénale aiguë, d'une infection urinaire ou d'un sepsis); 2) toute autre cause de visite à l'hôpital; 3) toute autre cause d'admission; et 4) toute autre cause de visite aux urgences. MÉTHODOLOGIE: Une régression de Poisson modifiée a été employée pour l'analyze des résultats sur les variables démographiques, l'utilization des soins de santé au cours de l'année précédente, les différentes procédures et maladies concomitantes liées au résultat au cours des cinq années précédentes et les médicaments prescrits au cours des 120 derniers jours afin de comparer le rapport de risque (RR) de chaque résultat entre les patients atteints ou non d'ADPKD. RÉSULTATS: L'âge médian des sujets (écart interquartile) s'établissait à 44 ans (38-60 ans) dans le groupe de patients ADPKD et à 53 ans (42-64 ans) dans le groupe témoin; les femmes représentaient environ 40 % des sujets dans les deux groupes. Le risque de complications liées à l'urétéroscopie n'était pas significativement différent entre le groupe ADPKD et le groupe témoin (8,2 % vs 4,2 %; RR corrigé: 1,5; IC 95 %: 0,7 à 3,2). Tous les patients, avec ou sans ADPKD, étaient plus susceptibles de se présenter à l'hôpital après l'intervention (36,6 % vs 20,0 %; RR corrigé: 1,6; IC 95 %: 1,2 à 2,2). Ce résultat incluait un risque significativement plus élevé de se présenter aux urgences (32,9 % vs 19,0 %; RR corrigé: 1,6; IC 95 %: 1,1 à 2,2), mais pas d'être hospitalisé (11 % vs 5 %; RR corrigé: 1,8; IC 95 %: 0,9 à 3,4). LIMITES: Le faible nombre d'événements a mené à l'imprécision des estimations. CONCLUSION: Les patients atteints d'ADPKD présentent un risque accru de retourner à l'hôpital dans les 30 jours suivant une urétéroscopie pour traiter des calculs urinaires. ENREGISTREMENT DE L'ESSAI: L'étude n'a pas été enregistrée.

Kidney Function and Potassium Monitoring After Initiation of Renin-Angiotensin-Aldosterone System Blockade Therapy and Outcomes in 2 North American Populations.

BACKGROUND: Clinical practice guidelines recommend routine kidney function and serum potassium testing within 30 days of initiating ACE (angiotensin-converting enzyme) inhibitor or angiotensin II receptor blocker therapy. However, evidence is lacking about whether follow-up testing reduces therapy-related adverse outcomes. METHODS AND RESULTS: We conducted 2 population-based retrospective cohort studies in Kaiser Permanente Northern California and Ontario, Canada. Patients with outpatient serum creatinine and potassium tests in the 30 days after starting ACE inhibitor or angiotensin II receptor blocker therapy were matched 1:1 to patients without follow-up tests. We evaluated the association of follow-up testing with 30-day all-cause mortality and hospitalization with acute kidney injury or hyperkalemia using Cox regression. We also developed and externally validated a risk score to identify patients at risk of having abnormally high serum creatinine and potassium values in follow-up. We identified 75 251 matched pairs initiating ACE inhibitor or angiotensin II receptor blocker therapy between January 1, 2007, and December 31, 2017, in Kaiser Permanente Northern California. Follow-up testing was not significantly associated with 30-day all-cause mortality in Kaiser Permanente Northern California (hazard ratio, 0.75 [95% CI, 0.54-1.06]) and was associated with higher mortality in 84 905 matched pairs in Ontario (hazard ratio, 1.32 [95% CI, 1.07-1.62]). In Kaiser Permanente Northern California, follow-up testing was significantly associated with higher rates of hospitalization with acute kidney injury (hazard ratio, 1.66 [95% CI, 1.10-2.22]) and hyperkalemia (hazard ratio, 3.36 [95% CI, 1.08-10.41]), as was observed in Ontario. The risk score for abnormal potassium provided good discrimination (area under the curve [AUC], 0.75) and excellent calibration of predicted risks, while the risk score for abnormal serum creatinine provided moderate discrimination (AUC, 0.62) but excellent calibration. CONCLUSIONS: Routine laboratory monitoring after ACE inhibitor or angiotensin II receptor blocker initiation was not associated with a lower risk of 30-day mortality. We identified patient subgroups in which targeted testing may be effective in identifying therapy-related changes in serum potassium or kidney function.

Efficacy and Safety of Surgical Kidney Stone Interventions in Autosomal Dominant Polycystic Kidney Disease: A Systematic Review.

BACKGROUND: Reduced kidney function and distorted kidney anatomy in patients with autosomal dominant polycystic kidney disease (ADPKD) may complicate stone interventions more compared with the general population. OBJECTIVES: To review studies describing the safety and efficacy of the 3 main stone interventions in adults with ADPKD: shock wave lithotripsy (SWL), ureteroscopy, and percutaneous nephrolithotomy (PCNL). DESIGN: Systematic review. SETTING: Any country of origin. PATIENTS: Adults with ADPKD who underwent SWL, ureteroscopy, or PCNL. MEASUREMENTS: Being stone free after the intervention and postoperative complications as reported by each study, which included pain, bleeding, and fever. METHODS: Relevant studies published until February 2019 were identified through a comprehensive search of MEDLINE, EMBASE, Web of Science, BIOSIS PREVIEW, and CINAHL. Studies were eligible for review if they reported at least one outcome following SWL, ureteroscopy, and/or PCNL in adults with ADPKD. We then abstracted information on study characteristics, patient characteristics, intervention details, and postintervention outcomes and assessed the methodological quality of each study using a modified Downs and Black checklist. RESULTS: We screened 221 citations from which we identified 24 studies that met our review criteria. We identified an additional article when manually reviewing the reference list of an included article, yielding a total of 25 studies describing 311 patients (32 SWL, 42 ureteroscopy, and 237 PCNL). The percentage of patients who were stone free after 1 session ranged from 0% to 69% after SWL, 73% to 100% after ureteroscopy, and 45% to 100% after PCNL. The percentage of patients with ADPKD that experienced at least one postoperative complication ranged from 0% to 33% for SWL, 0% to 27% for ureteroscopy, and 0% to 100% for PCNL. LIMITATIONS: The number and quality of studies published to date are limited. CONCLUSIONS: The efficacy and safety of stone interventions in patients with ADPKD remains uncertain, with wide-ranging estimates reported in the literature. TRIAL REGISTRATION: We did not register the protocol of this systematic review.

CONTEXTE: Les interventions visant à traiter les calculs rénaux sont plus compliquées chez les patients atteints de polykystose rénale autosomique dominante (ADPKD) que dans la population générale en raison de la fonction rénale réduite et des distorsions anatomiques des reins présentes chez ces patients. OBJECTIF: Passer en revue les études portant sur l'innocuité et l'efficacité des trois principales interventions pour traiter les calculs rénaux chez des adultes atteints d'ADPKD: la lithotripsie par ondes de choc (LOC), l'urétéroscopie et la néphrolithotomie percutanée (NLPC). TYPE D'ÉTUDE: Revue systématique. CADRE: Les pays d'origine des études. SUJETS: Des adultes atteints d'ADPKD ayant subi une LOC, une urétéroscopie ou une NLPC. MESURES: Une intervention réussie (absence de calculs rénaux) et les complications postopératoires rapportées (douleur, hémorragie et fièvre). MÉTHODOLOGIE: Une recherche exhaustive sur MEDLINE, EMBASE, Web of Science, BIOSIS PREVIEW et CINAHL a permis de répertorier toutes les études pertinentes publiées jusqu'en février 2019. Les études devaient rapporter minimalement une des mesures d'intérêt à la suite d'une LOC, d'une urétéroscopie ou d'une NLPC chez des adultes atteints d'ADPKD. Les caractéristiques des études, les caractéristiques des patients, les détails de l'intervention et les résultats postopératoires ont été extraits des études retenues. La qualité méthodologique de chaque étude a été mesurée selon la grille d'évaluation de Downs et Black. RÉSULTATS: Des 221 citations répertoriées par la revue de la littérature, 24 études satisfaisaient nos critères d'inclusion. Une 25e étude s'est ajoutée en passant en revue manuellement les références d'un des essais déjà inclus. Notre revue systématique porte donc sur un total de 311 patients (32 LOC, 42 urétéroscopie et 237 NLPC). Le pourcentage de patients sans calculs rénaux après une seule intervention variait de 0 à 69 % après une LOC, de 73 à 100 % après une urétéroscopie et de 45 à 100 % après une NLPC. Le pourcentage de patients ayant souffert d'au moins une complication postopératoire variait de 0 à 33 % après une LOC, de 0 à 27 % pour une urétéroscopie et de 0 à 100 % pour une NLPC. LIMITES: Le nombre et la qualité des études publiées sur le sujet sont limités. CONCLUSION: L'efficacité et l'innocuité des interventions visant le retrait de calculs rénaux chez des patients atteints d'ADPKD demeurent incertaines; les estimations rapportées dans la littérature présentent une grande variété. ENREGISTREMENT DE L'ESSAI: Le protocole de cette revue systématique n'a pas été enregistré.