Estimating the population-level impacts of improved uptake of SGLT2 inhibitors in patients with chronic kidney disease: a cross-sectional observational study using routinely collected Australian primary care data

Background

Sodium glucose co-transporter 2 (SGLT2) inhibitors reduce the risk of kidney failure and death in patients with chronic kidney disease (CKD) but are underused. We evaluated the number of patients with CKD in Australia that would be eligible for treatment and estimated the number of cardiorenal and kidney failure events that could be averted with improved uptake of SGLT2 inhibitors.

Methods

This cross-sectional observational study leveraged nationally representative primary care data from 392 Australian general practices (MedicineInsight) between 1 January 2020 and 31 December 2021. We identified patients that would have met inclusion criteria of key SGLT2 inhibitor trials and applied these data to age and sex-stratified estimates of CKD prevalence for the Australian population (using national census data), estimating the number of preventable events using trial event rates. Key outcomes included cardiorenal events (CKD progression, kidney failure, or death due to cardiovascular or kidney disease) and kidney failure.

Findings

In MedicineInsight, 44.2% of adults with CKD would have met CKD eligibility criteria for an SGLT2 inhibitor; baseline use was 4.1%. Applying these data to the Australian population, 230,246 patients with CKD would have been eligible for treatment with an SGLT2 inhibitor. Optimal implementation of SGLT2 inhibitors (75% uptake) could reduce cardiorenal and kidney failure events annually in Australia by 3644 (95% CI 3526-3764) and 1312 (95% CI 1242-1385), respectively.

Interpretation

Improved uptake of SGLT2 inhibitors for patients with CKD in Australia has the potential to prevent large numbers of patients experiencing CKD progression or dying due to cardiovascular or kidney disease. Identifying strategies to increase the uptake of SGLT2 inhibitors is critical to realising the population-level benefits of this drug class.

Funding

University of New South Wales Scientia Program and Boehringer IngelheimEli Lilly Alliance.

20-year trends in multimorbidity by race/ethnicity among hospitalized patient populations in the United States

BACKGROUND

The challenges presented by multimorbidity continue to rise in the United States. Little is known about how the relative contribution of individual chronic conditions to multimorbidity has changed over time, and how this varies by race/ethnicity. The objective of this study was to describe trends in multimorbidity by race/ethnicity, as well as to determine the differential contribution of individual chronic conditions to multimorbidity in hospitalized populations over a 20-year period within the United States.

METHODS

This is a serial cross-sectional study using the Nationwide Inpatient Sample (NIS) from 1993 to 2012. We identified all hospitalized patients aged ≥ 18 years old with available data on race/ethnicity. Multimorbidity was defined as the presence of 3 or more conditions based on the Elixhauser comorbidity index. The relative change in the proportion of hospitalized patients with multimorbidity, overall and by race/ethnicity (Black, White, Hispanic, Asian/Pacific Islander, Native American) were tabulated and presented graphically. Population attributable fractions were estimated from modified Poisson regression models adjusted for sex, age, and insurance type. These fractions were used to describe the relative contribution of individual chronic conditions to multimorbidity over time and across racial/ethnic groups.

RESULTS

There were 123,613,970 hospitalizations captured within the NIS between 1993 and 2012. The prevalence of multimorbidity increased in all race/ethnic groups over the 20-year period, most notably among White, Black, and Native American populations (+ 29.4%, + 29.7%, and + 32.0%, respectively). In both 1993 and 2012, Black hospitalized patients had a higher prevalence of multimorbidity (25.1% and 54.8%, respectively) compared to all other race/ethnic groups. Native American populations exhibited the largest overall increase in multimorbidity (+ 32.0%). Furthermore, the contribution of metabolic diseases to multimorbidity increased, particularly among Hispanic patients who had the highest population attributable fraction values for diabetes without complications (15.0%), diabetes with complications (5.1%), and obesity (5.8%).

CONCLUSIONS

From 1993 to 2012, the secular increases in the prevalence of multimorbidity as well as changes in the differential contribution of individual chronic conditions has varied substantially by race/ethnicity. These findings further elucidate the racial/ethnic gaps prevalent in multimorbidity within the United States.

PRIOR PRESENTATIONS

Preliminary finding of this study were presented at the Society of General Internal Medicine (SGIM) Annual Conference, Washington, DC, April 21, 2017.

Use of Google Analytics to Explore Dissemination Activities for an Online CKD Clinical Pathway: A Retrospective Study

Background:

Data on dissemination strategies that generate awareness of clinical pathways for kidney care are limited.

Objective:

This study reports the application of Google Analytics to describe the reach and use of the Chronic Kidney Disease Pathway (CKD-P) using a multi-faceted dissemination strategy.

Design:

The design of this study is a retrospective descriptive study.

Setting:

This study was conducted in Alberta, Canada.

Patients:

Individuals who accessed the CKD-P Web site between November 5, 2014, and May 31, 2019.

Measurements:

Dissemination activities included print, electronic, in-person meetings, and a laboratory prompt. We used Google Analytics over a 5-year period to evaluate the following CKD-P Web site user metrics: number of sessions, pageviews, visit duration, user path, and bounce rate (when an individual visits a single page of the Web site and leaves the Web site without interacting with additional pages).

Methods:

We plotted dissemination activities alongside Web site metrics using control charts and described the data using means and percentages. We performed chi-square test for trends to evaluate year-over-year usage.

Results:

There were 83 294 users, 90 805 sessions, and 231 684 pageviews. The overall bounce rate was 45.7%. Each user had an average of 1.5 sessions and a session duration of 2 minutes and 8 seconds. There was a significant positive trend for total annual users (P = .008), new users (P = .009), number of sessions (P = .006), and pageviews per day (P = .016).

Limitations:

We were unable to confirm if users were primary care providers and if word-of-mouth dissemination among providers/researchers drove people to use the CKD-P.

Conclusions:

Google Analytics was a useful and accessible tool for evaluating CKD-P reach and use trends. It was challenging to identify how individual dissemination activities contributed to CKD-P reach; however, repeated dissemination appeared to play a role in increasing CKD-P use.

Trial registration:

Not applicable—observational study design.

Identifying subgroups of adult high-cost health care users: a retrospective analysis

BACKGROUND

Few studies have categorized high-cost patients (defined by accumulated health care spending above a predetermined percentile) into distinctive groups for which potentially actionable interventions may improve outcomes and reduce costs. We sought to identify homogeneous groups within the persistently high-cost population to develop a taxonomy of subgroups that may be targetable with specific interventions.

METHODS

We conducted a retrospective analysis in which we identified adults (≥ 18 yr) who lived in Alberta between April 2014 and March 2019. We defined "persistently high-cost users" as those in the top 1% of health care spending across 4 data sources (the Discharge Abstract Database for inpatient encounters; Practitioner Claims for outpatient primary care and specialist encounters; the Ambulatory Care Classification System for emergency department encounters; and the Pharmaceutical Information Network for medication use) in at least 2 consecutive fiscal years. We used latent class analysis and expert clinical opinion in tandem to separate the persistently high-cost population into subgroups that may be targeted by specific interventions based on their distinctive clinical profiles and the drivers of their health system use and costs.

RESULTS

Of the 3 919 388 adults who lived in Alberta for at least 2 consecutive fiscal years during the study period, 21 115 (0.5%) were persistently high-cost users. We identified 9 subgroups in this population: people with cardiovascular disease (n = 4537; 21.5%); people receiving rehabilitation after surgery or recovering from complications of surgery (n = 3380; 16.0%); people with severe mental health conditions (n = 3060; 14.5%); people with advanced chronic kidney disease (n = 2689; 12.7%); people receiving biologic therapies for autoimmune conditions (n = 2538; 12.0%); people with dementia and awaiting community placement (n = 2520; 11.9%); people with chronic obstructive pulmonary disease or other respiratory conditions (n = 984; 4.7%); people receiving treatment for cancer (n = 832; 3.9%); and people with unstable housing situations or substance use disorders (n = 575; 2.7%).

INTERPRETATION

Using latent class analysis supplemented with expert clinical review, we identified 9 policy-relevant subgroups among persistently high-cost health care users. This taxonomy may be used to inform policy, including identifying interventions that are most likely to improve care and reduce cost for each subgroup.

Mortality and cardiovascular events in adults with kidney failure after major non-cardiac surgery: a population-based cohort study

BACKGROUND

People with kidney failure have a high incidence of major surgery, though the risk of perioperative outcomes at a population-level is unknown. Our objective was to estimate the proportion of people with kidney failure that experience acute myocardial infarction (AMI) or death within 30 days of major non-cardiac surgery, based on surgery type.

METHODS

In this retrospective population-based cohort study, we used administrative health data to identify adults from Alberta, Canada with major surgery between April 12,005 and February 282,017 that had preoperative estimated glomerular filtration rates (eGFRs) < 15 mL/min/1.73m2 or received chronic dialysis. The index surgical procedure for each participant was categorized within one of fourteen surgical groupings based on Canadian Classification of Health Interventions (CCI) codes applied to hospitalization administrative datasets. We estimated the proportion of people that had AMI or died within 30 days of the index surgical procedure (with 95% confidence intervals [CIs]) following logistic regression, stratified by surgery type.

RESULTS

Overall, 3398 people had a major surgery (1905 hemodialysis; 590 peritoneal dialysis; 903 non-dialysis). Participants were more likely male (61.0%) with a median age of 61.5 years (IQR 50.0-72.7). Within 30 days of surgery, 272 people (8.0%) had an AMI or died. The probability was lowest following ophthalmologic surgery at 1.9% (95%CI: 0.5, 7.3) and kidney transplantation at 2.1% (95%CI: 1.3, 3.2). Several types of surgery were associated with greater than one in ten risk of AMI or death, including retroperitoneal (10.0% [95%CI: 2.5, 32.4]), intra-abdominal (11.7% [8.7, 15.5]), skin and soft tissue (12.1% [7.4, 19.1]), musculoskeletal (MSK) (12.3% [9.9, 15.5]), vascular (12.6% [10.2, 15.4]), anorectal (14.7% [6.3, 30.8]), and neurosurgical procedures (38.1% [20.3, 59.8]). Urgent or emergent procedures had the highest risk, with 12.1% experiencing AMI or death (95%CI: 10.7, 13.6) compared with 2.6% (1.9, 3.5) following elective surgery.

CONCLUSIONS

After major non-cardiac surgery, the risk of death or AMI for people with kidney failure varies significantly based on surgery type. This study informs our understanding of surgery type and risk for people with kidney failure. Future research should focus on identifying high risk patients and strategies to reduce these risks.

86Segmenting persistently high-cost individuals into actionable groups

Background

Despite growing evidence describing high cost patients, decision-makers struggle to implement effective strategies to improve care and curb spending in this population. Using a multi-phased approach, we aimed to classify high cost patients into homogeneous subgroups amenable to targeted interventions.

Methods

We linked population-level administrative health data in Alberta, Canada from 2012-2017. We defined “persistently high-cost” as those in the top 1% of cumulative inpatient, outpatient and medication cost in at least two consecutive years. We used latent class analysis to separate this persistent high-cost population into potentially actionable subgroups.

Results

Of the 3,795,067 adults residing in Alberta, 21,361 were ‘persistently high-cost’. Latent class models identified 10 high-cost subgroups: individuals with CKD (19.3% of persistent high-cost individuals), those undergoing joint surgery/replacement and rehabilitation (18.6%), individuals with IBD (11.6%), patients receiving biologics for autoimmune conditions (11.3%), patients receiving high cost drugs for other conditions (11.1%), community-dwelling individuals with multimorbid chronic conditions (9.0%), individuals with schizophrenia (6.8%), individuals with other mental health issues (6.2%), rural individuals with COPD (3.4%), and frail elderly in institutional settings (2.7%).

Conclusions

Latent class analysis was able to identify 10 persistently high-cost groups based on meaningful differences in health care spending, demographics, and clinical diagnoses.

Key messages

This taxonomy will inform the identification of interventions shown to improve care and reduce cost for each subgroup in addition to consultation with key stakeholders to identify and reflect on key barriers and facilitators to implementing identified interventions within the local context.

Cost of Potentially Preventable Hospitalizations Among Adults With Chronic Kidney Disease: A Population-Based Cohort Study

Background:

Prior studies report high hospitalization rates among patients with chronic kidney disease (CKD) and approximately 10% to 20.9% of hospitalizations are potentially preventable.

Objective:

To determine the rate, proportion, and cost of potentially preventable hospitalizations and whether this varied by CKD category.

Design:

Retrospective cohort study using population-based data.

Setting:

Alberta, Canada.

Patients:

All adults with an outpatient serum creatinine measurement between January 1 and December 31, 2017 in the Alberta Kidney Disease Network data repository.

Measurements:

CKD risk categories were based on measures of proteinuria (where available), eGFR, and use of dialysis. Patients were linked to administrative data to capture frequency and cost of hospital encounters and followed until death or end of study (December 31, 2018). The outcomes of interest were the rate and cost of potentially preventable hospitalizations, as identified using the Canadian Institute for Health Information (CIHI)-defined ambulatory care sensitive condition (ACSC) algorithm and a CKD-related ACSC algorithm.

Methods:

Unadjusted and adjusted rates per 1000-patient years, proportions, and cost attributable to preventable hospitalizations were identified for the cohort as a whole and for patients within each CKD risk category.

Results:

Of the 1,110,895 adults with eGFR and proteinuria measurements, 181,422 had CKD. During a median follow-up of 1 year, there were 62,023 hospitalizations among patients with CKD resulting in a total cost of $946 million CAD; 6907 (11.1%) of these hospitalizations were for CIHI-defined ACSCs while 4323 (7.0%) were for CKD-related ACSCs. Adjusted rates of hospitalization for ACSCs increased with CKD risk category and were highest among patients treated with dialysis. Among CKD patients, the total cost of potentially preventable hospitalizations was $79 million and $58 million CAD for CIHI-defined and CKD-related ACSCs (8.4% and 6.2% of total hospitalization cost, respectively).

Limitations:

Based on the ACSC construct, we were unable to determine if these hospitalizations were truly preventable.

Conclusions:

Potentially preventable hospitalizations have a substantial cost and burden on the health care system among people with CKD. Effective strategies that reduce preventable admissions among CKD patients may lead to significant cost savings.

Trial registration:

Not applicable—observational study design

Impact of physiologically relevant temperatures on dermal absorption of active substances - an ex-vivo study in human skin

Skin temperature plays a certain role in the dermal absorption of substances, but the extent and mechanisms of skin temperatures-induced modulation in ranges caused by physiological thermoregulation or environmental conditions are largely unknown. The influence of dermal temperature on the absorption of the model lipophilic compound (anisole) and the model hydrophilic compounds (1,4-dioxane, ethanol) through human skin was investigated at three dermal temperatures (25, 32 and 39 °C) in an ex-vivo diffusion cell model. The substances were applied to the skin and transdermal penetration was monitored. All substances showed temperature dependent variations in their penetration behavior (3 h: 25-39 °C: 202-275% increase in cumulative, transdermally penetrated amounts). The relative differences in absorption in relation to temperature were greatest within 45 min after exposure (25-39 °C: 347-653% rise in cumulated penetration), although absolute amounts absorbed were small (45 min vs. 3 h: 4.5-14.5%). Regardless of blood circulation, skin temperature significantly influences the amount and kinetics of dermal absorption. Substance-dependent, temperature-related changes of the lipid layer order or the porous pathway may facilitate penetration. The early-stage modulation of transdermal penetration indicates transappendageal absorption, which may be relevant for short-term exposures. For both, toxicological evaluation and perfusion cell studies, it is important to consider the thermal influence on absorption or to perform the latter at a standardized temperature (32±1 °C).

Comparing Onset of Biosimilar Versus Generic Competition in the United States

We sought to compare expected and observed biosimilar and generic entry dates among new drugs approved by the US Food and Drug Administration (FDA) between 2000 and 2012. We defined expected biosimilar and generic entry dates as the later of the expiration of the key patent term or statutory exclusivity (12 years for biologics, 5 years for small molecule drugs not indicated for a rare disease, and 7 years for small molecule drugs indicated for a rare disease; plus 6 months if a pediatric extension had been granted). For drugs with expected entry prior to 2019, we calculated the proportion with observed biosimilar or generic entry. The expected biosimilar entry dates were estimated to be a median of 12.3 years (interquartile range (IQR) 12.0-14.0, n = 60) after FDA approval. The 12-year biologic statutory exclusivity period comprised 98% of the median expected protection period. By contrast, expected generic entry was estimated to be a median of 12.2 years (IQR 8.4-14.0, n=268), or 7.2 years after the 5-year small molecule statutory exclusivity (59% of the total expected market protection period). By 2019, observed biosimilar entry occurred in 12% of cases (3/25) and observed generic entry in 65% (101/155). We concluded that expected US market exclusivity periods are similar for biologic and small molecule drugs. Statutory exclusivity plays a more substantial role in market exclusivity protection for biologics. Biosimilar competition, currently lagging behind generic competition, will likely increase as the biosimilar market becomes established.

Quality of Chronic Kidney Disease Management in Canadian Primary Care

IMPORTANCE

Although patients with chronic kidney disease (CKD) are routinely managed in primary care settings, no nationally representative study has assessed the quality of care received by these patients in Canada.

OBJECTIVE

To evaluate the current state of CKD management in Canadian primary care practices to identify care gaps to guide development and implementation of national quality improvement initiatives.

DESIGN, SETTING, AND PARTICIPANTS

This cross-sectional study leveraged Canadian Primary Care Sentinel Surveillance Network data from January 1, 2010, to December 31, 2015, to develop a cohort of 46 162 patients with CKD managed in primary care practices. Data analysis was performed from August 8, 2018, to July 31, 2019.

MAIN OUTCOMES AND MEASURES

The study examined the proportion of patients with CKD who met a set of 12 quality indicators in 6 domains: (1) detection and recognition of CKD, (2) testing and monitoring of kidney function, (3) use of recommended medications, (4) monitoring after initiation of angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin II receptor blockers (ARBs), (5) management of blood pressure, and (6) monitoring for glycemic control in those with diabetes and CKD. The study also analyzed associations of divergence from these quality indicators.

RESULTS

The cohort comprised 46 162 patients (mean [SD] age, 69.2 [14.0] years; 25 855 [56.0%] female) with stage 3 to 5 CKD. Only 4 of 12 quality indicators were met by 75% or more of the study cohort. These indicators were receipt of an outpatient serum creatinine test within 18 months after confirmation of CKD, receipt of blood pressure measurement at any time during follow-up, achieving a target blood pressure of 140/90 mm Hg or lower, and receiving a hemoglobin A1c test for monitoring diabetes during follow-up. Indicators in the domains of detection and recognition of CKD, testing and monitoring of kidney function (specifically, urine albumin to creatinine ratio testing), use of recommended medications, and appropriate monitoring after initiation of treatment with ACEIs or ARBs were not met. Only 6529 patients (18.4%) with CKD received a urine albumin test within 6 months of CKD diagnosis, and 3954 (39.4%) had a second measurement within 6 months of an abnormal baseline urine albumin level. Older age (≥85 years) and CKD stage 5 were significantly associated with not satisfying the criteria for the quality indicators across all domains. Across age categories, younger patients (aged 18-49 years) and older patients (≥75 years) were less likely to be tested for albuminuria (314 of 1689 patients aged 18-49 years [18.5%], 1983 of 11 919 patients aged 75-84 years [61.6%], and 614 of 5237 patients aged ≥85 years [11.7%] received the urine albumin to creatinine ratio test within 6 months of initial estimated glomerular filtration rate <60 mL/min per 1.73 m2; P < .001). Patients aged 18 to 49 years were less commonly prescribed recommended medications (222 of 2881 [7.7%]), whereas patients aged 75 to 84 years were prescribed ACEIs or ARBs most frequently (2328 of 5262 [44.2%]; P < .001).

CONCLUSIONS AND RELEVANCE

The findings suggest that management of CKD across primary care practices in Canada varies according to quality indicator. This study revealed potential priority areas for quality improvement initiatives in Canadian primary care practices.

Prevalence and Demographics of CKD in Canadian Primary Care Practices: A Cross-sectional Study

Introduction

Surveillance systems enable optimal care delivery and appropriate resource allocation, yet Canada lacks a dedicated surveillance system for chronic kidney disease (CKD). Using data from the Canadian Primary Care Sentinel Surveillance Network (CPCSSN), a national chronic disease surveillance system, this study describes the geographic, sociodemographic, and clinical variations in CKD prevalence in the Canadian primary care context.

Methods

This cross-sectional study included 559,745 adults in primary care in 5 provinces across Canada from 2010 through 2015. Data were analyzed by geographic (urban or rural residence), sociodemographic (age, sex, deprivation index), and clinical (medications prescribed, comorbid conditions) factors, using data from CPCSSN and the Canadian Deprivation Index. CKD stage 3 or higher was defined as 2 estimated glomerular filtration rate (eGFR) values of <60 ml/min per 1.73 m² more than 90 days apart as of January 1, 2015.

Results

Prevalence of CKD was 71.9 per 1000 individuals and varied by geography, with the highest prevalence in rural settings compared with urban settings (86.2 vs. 68.4 per 1000). CKD was highly prevalent among individuals with 3 or more other chronic diseases (281.7 per 1000). Period prevalence of CKD indicated a slight decline over the study duration, from 53.4 per 1000 in 2010 to 46.5 per 1000 in 2014.

Conclusion

This is the first study to estimate the prevalence of CKD in primary care in Canada at a national level. Results may facilitate further research, prioritization of care, and quality improvement activities to identify gaps and improvement in CKD care.

Racial disparities in comorbidity and severe maternal morbidity/mortality in the United States: an analysis of temporal trends

INTRODUCTION

Severe maternal morbidity and mortality have increased in the USA in recent years. This trend has not been consistent across all racial groups. The reasons behind this, and the relation between preexisting conditions, pregnancy-associated disease and severe maternal morbidity/mortality, have not been fully explored.

MATERIAL AND METHODS

Annual data on delivery hospitalizations between 1993 and 2012 were obtained from the Nationwide Inpatient Sample (NIS), representing a 20% sample of hospital discharges from across the USA. Chi-square tests for trend were used to examine temporal patterns in the proportion of pregnancies affected by comorbidities as defined by the Obstetric Comorbidity Score and were stratified by maternal race. Logistic regression was used to determine the impact of temporal increases in comorbidity on severe maternal morbidity/mortality.

RESULTS

In 1993, 34.3% of pregnancies had a comorbidity score of ≥1; this significantly increased to 44.1% by 2012 (p < 0.001). Baseline differences were observed between all races (Whites 33.7%, Blacks 34.5%, Hispanics 28.0%, Asian/Pacific Islanders 28.1%). Although significant increases were observed for all races, the relative rate of change was lowest for Whites (26.1% increase) and highest for Asian/Pacific Islanders (49.1% increase). The odds of severe maternal morbidity/mortality have steadily increased over time; however, adjustment for Obstetric Comorbidity Score significantly attenuates this correlation.

CONCLUSION

The rate of both preexisting comorbidities and pregnancy-associated disease is increasing in pregnant women in the USA and varies substantially by race. These trends provide valuable insight into the increasing complexity of pregnancy in the USA and explain a proportion of the observed increase in severe maternal morbidity/mortality.

Comparison of Methods to Define High Use of Inpatient Services Using Population-Based Data

BACKGROUND

A variety of methods have been proposed to define "high users" of inpatient services, which may have implications for targeting subgroups for intervention.

OBJECTIVE

To compare 3 common definitions of high inpatient service use and their influence on patient capture, outcomes, and inpatient burden.

DESIGN, SETTING, PATIENTS

We defined "high use" based on the upper 5th percentile of the population by 3 definitions: (1) number of inpatient episodes (≥3 hospitalizations/year), (2) cumulative length of stay (≥56 days in hospital/year), and (3) cumulative cost based on hospitalization resource intensity weights (≥ $63,597 Canadian dollars/year). Clinical characteristics, health outcomes, and overall health burden were compared across definitions and stratified by age.

RESULTS

Of that population, 10.3% of individuals were common to all definitions. High users based on number of inpatient episodes were more likely to be admitted for acute conditions, with most high users based on length of stay admitted for mental health-related conditions, while those based on costs were more likely to have hospitalizations resulting in death (9.3%). High-episode individuals accounted for 16.6% of all inpatient episodes, high-length of stay individuals for 46.4% of all hospital days, and high-cost individuals for 38.9% of total cost.

CONCLUSIONS

Three definitions of high users of inpatient services captured significantly different groups of patients. This has implications for targeting subgroups for intervention and highlights important considerations for selecting the most suitable definition for a given objective.

Potentially Preventable Hospitalization among Patients with CKD and High Inpatient Use

BACKGROUND AND OBJECTIVES

Although patients with CKD are commonly hospitalized, little is known about those with frequent hospitalization and/or longer lengths of stay (high inpatient use). The objective of this study was to explore clinical characteristics, patterns of hospital use, and potentially preventable acute care encounters among patients with CKD with at least one hospitalization.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We identified all adults with nondialysis CKD (eGFR<60 ml/min per 1.73 m2) in Alberta, Canada between January 1 and December 31, 2009, excluding those with prior kidney failure. Patients with CKD were linked to administrative data to capture clinical characteristics and frequency of hospital encounters, and they were followed until death or end of study (December 31, 2012). Patients with one or more hospital encounters were categorized into three groups: persistent high inpatient use (upper 5% of inpatient use in 2 or more years), episodic high use (upper 5% in 1 year only), or nonhigh use (lower 95% in all years). Within each group, we calculated the proportion of potentially preventable hospitalizations as defined by four CKD-specific ambulatory care sensitive conditions: heart failure, hyperkalemia, volume overload, and malignant hypertension.

RESULTS

During a median follow-up of 3 years, 57,007 patients with CKD not on dialysis had 118,671 hospitalizations, of which 1.7% of patients were persistent high users, 12.3% were episodic high users, and 86.0% were nonhigh users of hospital services. Overall, 24,804 (20.9%) CKD-related ambulatory care sensitive condition encounters were observed in the cohort. The persistent and episodic high users combined (14% of the cohort) accounted for almost one half (45.5%) of the total ambulatory care sensitive condition hospitalizations, most of which were attributed to heart failure and hyperkalemia. Risk of hospitalization for any CKD-specific ambulatory care sensitive condition was higher among older patients, higher CKD stage, lower income, registered First Nations status, and those with poor attachment to primary care.

CONCLUSIONS

Many hospitalizations among patients with CKD and high inpatient use are ambulatory care sensitive condition related, suggesting opportunities to improve outcomes and reduce cost by focusing on better community-based care for this population.

Autoantibodies to Dense Fine Speckles in Pediatric Diseases and Controls

OBJECTIVE

Autoantibodies to the dense fine speckled 70 kDa antigen (DFS70) are reported to be more common in individuals who do not have an antinuclear antibody (ANA)-associated rheumatic disease (AARD) than in patients with AARD. The frequency of anti-DFS70 antibodies has been thoroughly studied in adult but not in pediatric populations. The primary objective of this observational study was to determine the frequency of anti-DFS70 in pediatric AARD and reference cohorts.

METHODS

Sera from 743 children with AARD and related conditions, and 345 samples from reference cohorts (healthy children and those being investigated for AARD) were studied for anti-DFS70 autoantibodies as measured by a chemiluminescence immunoassay. A de-identified administrative database was used to retrieve demographic, serologic, and clinical data.

RESULTS

Anti-DFS70 antibodies were seen in 2.1% of healthy children and in 4.5% of sera from pediatric individuals referred for ANA testing. The frequency of anti-DFS70 was highest in juvenile localized scleroderma (LS; 4/29, 13.8%), juvenile dermatomyositis (JDM; 2/11, 18.2%), childhood systemic lupus erythematosus (cSLE; 19/331, 5.7%), diffuse cutaneous systemic sclerosis (1/22, 4.5%), celiac disease (2/49, 4.1%), and juvenile idiopathic arthritis (JIA; 5/202, 2.5%). Of note, anti-DFS70 antibodies were observed in 3/26 children (11.5%) with uveitis and JIA-associated uveitis.

CONCLUSION

The frequency of anti-DFS70 autoantibodies in healthy pediatric subjects is within the lower range of that reported in adults. Anti-DFS70 antibodies can be found in childhood SSc and cSLE, but has a remarkably high frequency in children with LS, JDM, and uveitis.

Patients with chronic kidney disease and their intent to use electronic personal health records

Background

Electronic personal health records (ePHRs) provide patients with access to their personal health information, aiming to inform them about their health, enhance self-management, and improve outcomes. Although they have been associated with improved health outcomes in several chronic diseases, the potential impact of ePHR use in chronic kidney disease (CKD) is unknown.

Objectives

We sought to understand perceptions of CKD patients about ePHRs, and describe characteristics associated with their expressed intent to use an ePHR.

Design

Self-administered paper based survey.

Setting

The study was conducted in Calgary, Alberta, Canada at a multidisciplinary CKD clinic from November 2013 to January 2014.

Participants

Patients with non-dialysis-dependent CKD.

Measurements

Demographics, perceived benefits, and drawbacks of ePHRs were obtained. A univariate analysis was used to assess for an association with the expressed intention to use an ePHR.

Methods

A patient survey was used to determine perceptions of ePHRs, and to identify factors that were associated with intention to use an ePHR.

Results

Overall 63 patients with CKD (76.2 % male, 55.6 % ≥65 years old) completed the survey. The majority (69.8 %) expressed their intent to use an ePHR. CKD patients over the age of 65 were less likely to intend to use an ePHR as compared to those aged <65 years (OR 0.22, 95 % CI: [0.06, 0.78]). Those with post-secondary education (OR 3.31, 95 % CI: [1.06, 10.41]) and Internet access (OR 5.70, 95 % CI: [1.64, 19.81]) were more likely to express their intent to use an ePHR. Perceived benefits of ePHR use included greater involvement in their own care (50.0 % indicated this), better access to lab results (75.8 %), and access to health information (56.5 %). Although 41.9 % reported concerns about privacy of health information, there was no association between these concerns and the intent to use an ePHR.

Limitations

Our results are limited by small study size and single centre location.

Conclusions

We found that patients with CKD expressed their intention to use ePHRs, and perceive benefits such as personal involvement in their health care and better access to lab results. Studies of CKD patients using ePHRs are needed to determine whether ePHR use improves patient outcomes.

Autoantibodies to the Rpp25 component of the Th/To complex are the most common antibodies in patients with systemic sclerosis without antibodies detectable by widely available commercial tests

OBJECTIVE

Antinuclear antibodies (ANA) occur in up to 95% of patients with systemic sclerosis (SSc). In most, SSc-associated antibodies are detected (i.e., centromere, topoisomerase I, RNA polymerase III, PM/Scl, Ro52/TRIM21, and U1RNP). Ribonuclease P protein subunit p25, (Rpp25) is an autoantigenic component of the Th/To complex. The contribution of anti-Th/To and anti-Rpp25 antibodies to ANA positivity in patients with SSc remains unknown.

METHODS

Sera from 873 patients with SSc were tested for ANA, and SSc-associated antibodies were measured. Samples without antibodies to extractable nuclear antigens (ENA; n = 53, ANA+/ENA-), were analyzed by immunoprecipitation (IP) and metabolically labeled proteins and for anti-Rpp25 antibodies (n = 50) by a chemiluminescent immunoassay (CLIA) and Rpp25 ELISA.

RESULTS

Anti-Th/To antibodies occurred in 19/53 (36%), as determined by IP, and were the most common autoantibody in ANA+/ENA- SSc. Of those samples, 50/53 were available for additional testing by CLIA and ELISA. Anti-Rpp25 antibodies were detected in 12 (24% CLIA) or 10 (20% ELISA) of 50 patients. Receiver-operating characteristic curve analysis showed similar discrimination between Th/To IP-positive (n = 19) and -negative samples (n = 31) by CLIA and ELISA (area under the curve 0.90 vs 0.87; p = 0.6691). The positive percent agreement between IP and CLIA or ELISA was 12/19 (63.2%, 95% CI 38.4-83.7%) or 10/19 (52.6%, 95% CI 73.3-94.2%), respectively. Negative percent agreement was 100% for both assays.

CONCLUSION

Autoantibodies to the Th/To autoantigen are important in patients with SSc who have been considered negative for SSc-specific or SSc-associated antibodies by widely available commercial assays. Rpp25 can be considered a major target of anti-Th/To antibodies. Assays detecting anti-Th/To and anti-Rpp25 antibodies may be important in SSc.

Clinical and serological features of patients referred through a rheumatology triage system because of positive antinuclear antibodies

Background

The referral of patients with positive anti-nuclear antibody (ANA) tests has been criticized as an inappropriate use of medical resources. The utility of a positive ANA test in a central triage (CT) system was studied by determining the autoantibody profiles and clinical diagnoses of patients referred to rheumatologists through a CT system because of a positive ANA test.

Methods

Patients that met three criteria were included: (1) referred to Rheumatology CT over a three year interval; (2) reason for referral was a “positive ANA”; (3) were evaluated by a certified rheumatologist. The CT clinical database was used to obtain demographic and clinical information and a serological database was used to retrieve specific ANA and/or extractable nuclear antigen (ENA) test results. Clinical information was extracted from the consulting rheumatologist's report.

Results

15,357 patients were referred through the CT system; 643 (4.1%) of these because of a positive ANA and of these 263 (40.9%) were evaluated by a certified rheumatologist. In 63/263 (24%) of ANA positive patients, the specialist provided a diagnosis of an ANA associated rheumatic disease (AARD) while 69 (26.2%) had no evidence of any disease; 102 (38.8%) had other rheumatologic diagnoses and 29 (11%) had conditions that did not meet AARD classification criteria. Of ANA positive archived sera, 15.1% were anti-DFS70 positive and 91.2% of these did not have an AARD.

Conclusions

This is the first study to evaluate the serological and clinical features of patients referred through a CT system because of a positive ANA. The spectrum of autoantibody specificities was wide with anti-Ro52/TRIM21 being the most common autoantibody detected. Approximately 15% of referrals had only antibodies to DFS70, the vast majority of which did not have clinical evidence for an AARD. These findings provide insight into the utility of autoantibody testing in a CT system.

Use of decompressive craniectomy after severe head trauma

Ten percent of head injuries quality as "severe," requiring prompt diagnosis and treatment. This level I trauma center uses an aggressive approach to treatment of severe head injuries and, when indicated, intervenes with decompressive craniectomy. This article explains decompressive craniectomy, including indications, procedures, and protocols. The case studies presented highlight two patients with profound head injuries. Additionally, cranioplasty replacement of autograft flap is explained and discussed.