The Associations Between Opioid Use Disorder and Healthcare-Related Outcomes in Vaso-occlusive Crisis

BACKGROUND

In patients who experience frequent vaso-occlusive crises (VOC), opioid dependence may be due to a need for pain control as opposed to addiction; the implications of opioid use disorder (OUD) in this population are unclear.

OBJECTIVE

To compare outcomes in hospitalizations for VOC in those with a history of OUD to those without a history of OUD.

DESIGN

A retrospective assessment of hospitalizations for adults in the USA with a primary discharge diagnosis of VOC using the National Inpatient Sample database from 2016 to 2019. We also compared VOC hospitalizations to hospitalizations for all other reasons to assess differences in OUD-associated clinical factors.

PARTICIPANTS

In total, 273,460 hospitalizations for VOC; 23,120 (8.5%) of these hospital stays involved a secondary diagnosis of OUD.

MAIN MEASURES

Primary outcomes were length of hospital stay and cost. Mortality was a secondary outcome.

KEY RESULTS

Hospital length of stay was increased (mean 6.2 vs 4.9 days) in patients with OUD (adjusted rate ratio = 1.24, 95% CI 1.20-1.29, p < 0.001). Mean cost was also higher in those with OUD ($9076) than those without OUD ($8020, p < 0.001). Mortality was decreased in VOC hospitalizations in those with OUD, but the difference was not statistically significant (adjusted OR = 0.64, 95% CI 0.028-1.48, p = 0.30).

CONCLUSIONS

OUD is associated with increased length of stay and costs in patients with VOC. While there are many possible explanations, providers should consider undertreatment of pain due to addiction concerns as a potential factor; individualized pain plans to mitigate this challenge could be explored.

Staging and clean room: Constructs designed to facilitate transparency and reduce bias in comparative analyses of real-world data

PURPOSE

We describe constructs designed to protect the integrity of the results from comparative analyses using real-world data (RWD): staging and clean room.

METHODS

Staging involves performing sequential preliminary analyses and evaluating the population size available and potential bias before conducting comparative analyses. A clean room involves restricted access to data and preliminary results, policies governing exploratory analyses and protocol deviations, and audit trail. These constructs are intended to allow decisions about protocol deviations, such as changes to design or model specification, to be made without knowledge of how they might affect subsequent analyses. We describe an example for implementing staging with a clean room.

RESULTS

Stage 1 may involve selecting a data source, developing and registering a protocol, establishing a clean room, and applying inclusion/exclusion criteria. Stage 2 may involve attempting to achieve covariate balance, often through propensity score models. Stage 3 may involve evaluating the presence of residual confounding using negative control outcomes. After each stage, check points may be implemented when a team of statisticians, epidemiologists and clinicians masked to how their decisions may affect study outcomes, reviews the results. This review team may be tasked with making recommendations for protocol deviations to address study precision or bias. They may recommend proceeding to the next stage, conducting additional analyses to address bias, or terminating the study. Stage 4 may involve conducting the comparative analyses.

CONCLUSIONS

The staging and clean room constructs are intended to protect the integrity and enhance confidence in the results of analyses of RWD.

Contemporary Practice of Anemia Treatment Among Dialysis Patients in the United States

Introduction

The treatment of anemia is a major activity in the care of patients undergoing maintenance hemodialysis (HD). The comparative effectiveness of new pharmacologic treatments, relative to erythropoiesis-stimulating agents (ESAs), should be anticipated on the bases of controlled trials and current practice. We describe the contemporary practice of anemia treatment in a national cohort of patients undergoing maintenance HD.

Methods

We analyzed the United States Renal Data System (USRDS) data to identify adult patients undergoing in-facility HD in 2016 to 2019. Using the Consolidated Renal Operations in a Web-Enabled Network (CROWNWeb) dataset, we identified hemoglobin and ESA utilization (agent and cumulative dose) during each patient-month, as well as intravenous (IV) iron utilization, ferritin, and transferrin saturation. We compared ESA dosing during the study era to dosing in the Normal Hematocrit Cardiac Trial (NHCT), conducted in the 1990s. We assessed ESA hyporesponsiveness by estimating the prevalence of the following: (i) high erythropoietin resistance index (ERI) and (ii) either 3 or 6 consecutive months with hemoglobin <10 g/dl.

Results

Nearly two-thirds of patient-months had hemoglobin of 10.0 to 11.9 g/dl. Mean ESA utilization was 76.7% per month, with increasing use of pegylated epoetin beta. ESA dosing was stable; epoetin alfa dosing was slightly lower than in the low-target arm of the NHCT. The prevalence of ESA hyporesponsiveness was 22.2% if defined by high ERI, but only 2.1% to 6.0% if defined by 3 to 6 consecutive months with hemoglobin <10 g/dl. Median transferrin saturation was 22.3% with high ERI and persistently low hemoglobin.

Conclusion

Hemoglobin and ESA dosing distributions are stable, with epoetin alfa dosing below the low-target arm of the NHCT. Persistently low hemoglobin occurs infrequently and may reflect iron depletion.

Symptom Trajectories in the Electronic Health Record during the Transition to Maintenance Dialysis

How symptoms recorded in the electronic health record change during the transition to dialysis has not been fully explored. We used the Optum deidentified Integrated Claims-Clinical dataset to identify individuals with CKD stages 4 or 5 who transitioned to dialysis. We searched structured data elements from clinical notes, identified by natural language processing, for symptoms recorded across weekly intervals in the 6 months before and after dialysis initiation and estimated changes in the odds of a symptom being recorded with an interrupted time series analysis using segmented logistic regression. The cohort comprised 728 individuals (aged 68±13 years, 44% women, 56% White, 30% Black). Before dialysis initiation, 83% were recorded as having pain, 68% fatigue/weakness, 66% shortness of breath, 61% nausea/vomiting, and 37% difficulty concentrating. Before dialysis initiation, odds of pain being recorded increased (slope: odds ratio [OR] 1.02 per week, 95% confidence interval [CI], 1.01 to 1.03); initiation was associated with a decrease (intercept change: OR 0.70, 95% CI, 0.59 to 0.82). After initiation, odds of pain were unchanged (postdialysis slope: OR 1.00 per week, 95% CI, 0.99 to 1.01), although this represented an improved trajectory relative to the predialysis period (change in slope: OR 0.98 per week, 95% CI, 0.96 to 0.99). For fatigue/weakness, odds increased before initiation (OR 1.03 per week, 95% CI, 1.02 to 1.04) but decreased on initiation (OR 0.62, 95% CI, 0.51 to 0.75) and thereafter (OR 0.98 per week, 95% CI, 0.97 to 0.99), representing a reduction in slope (OR 0.95 per week, 95% CI, 0.94 to 0.97). Patterns for shortness of breath, nausea/vomiting, and difficulty concentrating were similar to those of pain. Thus, the odds of five key symptoms being recorded in the electronic health record increased over time in the 6 months before dialysis initiation, decreased immediately on initiation, and, generally, remained unchanged in the 6 months thereafter.

Increased Access, Persistent Disparities: Trends in Disparities in Peritoneal Dialysis (PD) Use, 2009-2019

Peritoneal dialysis (PD) use has increased in the United States since 2009, but how this has affected disparities in PD use is unclear. We used data from the United States Renal Data System to identify a cohort of incident dialysis patients from 2009 to 2019. We used logistic regression models to examine how odds of PD use changed by demographic characteristics. The incident PD population increased by 203% from 2009 to 2019, and the odds of PD use increased in every subgroup. PD use increased more among older people because the odds for those aged 75 years or older increased 15% more per 5-year period compared with individuals aged 18-44 years (odds ratio [OR] 1.68, 95% confidence interval [CI], 1.64 to 1.73 versus OR 1.46, 95% CI, 1.42 to 1.50). The odds of PD use increased 5% more per 5-year period among Hispanic people compared with White people (OR 1.58, 95% CI, 1.53 to 1.63 versus OR 1.51, 95% CI, 1.48 to 1.53). There was no difference in odds of PD initiation among people who were Black, Asian, or of another race. The odds of PD use increased 5% more for people living in urban areas compared with people living in nonurban areas (5-year OR 1.54, 95% CI, 1.52 to 1.56 versus 5-year OR 1.46, 95% CI, 1.42 to 1.50). The odds of PD use increased 7% more for people living in socioeconomically advantaged areas compared with people living in more deprived areas (5-year OR 1.60, 95% CI, 1.56 to 1.63 for neighborhoods with lowest Social Deprivation Index versus 5-year OR 1.50, 95% CI, 1.48 to 1.53 in the most deprived areas). Expansion of PD use led to a reduction in disparities for older people and for Hispanic people. Although PD use increased across all strata of socioeconomic deprivation, the gap in PD use between people living in the least deprived areas and those living in the most deprived areas widened.

A Collaborative Pilot to Support Patients With Diabetes Through Tailored Food Box Home Delivery

We conducted a randomized, controlled prospective pilot study to determine feasibility and impact of food bank and health system collaboration to home-delivered food to adults with type 2 diabetes mellitus experiencing food insecurity. Treatment group received biweekly, ethnically tailored, home-delivered food for 24 weeks. Analysis included intervention feasibility and impact on healthcare utilization, HbA1c, and other health-related measures. Intervention was feasible and successful with high levels of participant satisfaction. At baseline, participants with highest HbA1c reported poorer health, lower medication adherence and self-care, and higher diabetes distress and medicine for food tradeoffs. At 24 weeks, treatment group reported improved food security and health status. There were no differences in HbA1c or healthcare utilization measures between the two groups. It is feasible for a community food bank and nearby hospital to successfully collaborate and provide supplemental food staples to food insecure adults with type 2 diabetes and improve food insecurity and health status. Public policy efforts should utilize and expand this strategy with the goal of improving health and reducing health disparities. Future work could include more comprehensive food support focused on those with poorest glycemic control, and expanded, coordinated interventions directed at other social determinants of health. Future programming and policies should be cocreated with community input to ensure greatest success.

Association of the End-Stage Renal Disease Treatment Choices Payment Model With Home Dialysis Use at Kidney Failure Onset From 2016 to 2022

IMPORTANCE

The Centers for Medicare & Medicaid Services designed a mandatory payment model to incentivize home dialysis use: the End-Stage Renal Disease Treatment Choices (ETC). Outpatient dialysis facilities and health care professionals providing nephrology services were randomly assigned to ETC participation at the hospital referral region level.

OBJECTIVE

To assess the association between ETC and home dialysis use in the incident dialysis population in its first 18 months of implementation.

DESIGN, SETTING, AND PARTICIPANTS

A cohort study with controlled, interrupted time series analysis of the US End-Stage Renal Disease Quality Reporting System database was conducted, using generalized estimating equations. All adults initiating home-based dialysis in the US between January 1, 2016, and June 30, 2022, without a prior kidney transplant were included in the analysis.

EXPOSURES

Prior to vs after ETC onset in January 1, 2021, and random assignment to ETC participation of facilities and health care professionals involved in patient care.

MAIN OUTCOMES AND MEASURES

Percentage of patients started on incident home dialysis and yearly change in percentage initiating home dialysis.

RESULTS

A total of 817 177 adults initiated home dialysis during the study period, of whom 750 314 were included in the study cohort. The cohort included 41.4% women; 26.2% of the patients were Black, 17.4% were Hispanic, and 49.1% were White. Approximately half (49.6%) of the patients were aged at least 65 years. A total of 31.2% received care from health care professionals assigned to ETC participation, and 33.6% had Medicare fee-for-service coverage. Overall, home dialysis use increased from 10.0% in January 2016 to 17.4% in June 2022. Home dialysis use increased more in ETC markets than in non-ETC markets after January 2021 (by 1.07%; 95% CI, 0.16%-1.97%). The rate of increase in home dialysis use in the entire cohort nearly doubled after January 2021 to 1.66% per year (95% CI, 1.14%-2.19%) compared with before 2021, when the rate was 0.86% per year (95% CI, 0.75%-0.97%), but the difference in rate of increase in home dialysis use was not significant between ETC and non-ETC markets.

CONCLUSIONS AND RELEVANCE

This study noted that, although the overall rate of dialysis use at home was greater after ETC implementation, the increase occurred more among patients in ETC markets than among those in non-ETC markets. These findings suggest that federal policy and financial incentives affected care for the entire incident dialysis population in the US.

Associations of COVID-19 Outcomes with Dialysis Modalities and Settings

How maintenance dialysis modality, dialysis setting, and residence in a nursing facility have jointly associated with coronavirus disease 2019 (COVID-19)-related outcomes in the United States is relevant to future viral outbreaks. Using Medicare claims, we determined the incidence of COVID-19-related infection, hospitalization, and death between March 15, 2020 and June 5, 2021. The exposure was one of five combinations of dialysis modality and care setting: in-facility hemodialysis without a recent history of skilled nursing facility care, in-facility hemodialysis with a recent history of skilled nursing facility care, hemodialysis in a skilled nursing facility, home hemodialysis, and (home) peritoneal dialysis. Patient-weeks were pooled to estimate the adjusted associations of event incidence with each dialysis modality/setting during four intervals in 2020-2021. Relative to in-facility hemodialysis without a recent history of skilled nursing facility care, home dialysis was associated with 36%-60% lower odds of all events during weeks 12-23 of 2020; 24%-37% lower odds of all events during weeks 24-37 of 2020; 20%-33% lower odds of infection and hospitalization during the winter of 2020-2021; and similar odds of all events thereafter. In contrast, exposure to skilled nursing facilities was associated with 570%-1140% higher odds of all events during spring of 2020, although excess risk attenuated as the pandemic transpired, especially among patients who received hemodialysis in skilled nursing facilities. In conclusion, home dialysis was associated with lower risks of COVID-19 diagnosis, hospitalization, and death until vaccines were available, whereas care in skilled nursing facilities was associated with higher risks.

Kidney-Metabolic Factors Associated with Cognitive Impairment in Chronic Kidney Disease: A Pilot Study

INTRODUCTION

The associations of kidney-metabolic biomarkers with cognitive impairment (CI) beyond the estimated glomerular filtration rate (eGFR, in mL/min/1.73 m2) and albuminuria levels are not well understood. In exploratory analysis, our objective was to determine the extent that three kidney-metabolic factors, previously proposed as mechanisms of CI and commonly abnormal in chronic kidney disease (CKD), were associated with prevalent CI in CKD participants, adjusted for kidney function measures.

METHODS

The study cohort included community-dwelling individuals aged ≥45 years with CKD (eGFR <60), not requiring dialysis, recruited from four health systems. We examined the serum biomarkers bicarbonate (CO2), TNFαR1, and cholesterol as primary exposures. A structured neuropsychological battery conducted by trained staff measured global and domain-specific cognitive performance. Logistic regression analyses estimated the cross-sectional associations between kidney-metabolic measures and global and cognitive domain-specific moderate/severe (Mod/Sev) CI, adjusted for the eGFR, urinary albumin-creatinine ratio (UACR, mg/g), demographics, comorbid conditions, and other kidney-metabolic biomarkers commonly abnormal in CKD.

RESULTS

Among 436 CKD participants with mean age 70 years, 16% were Black, the mean eGFR was 34, and the median [IQR] UACR was 49 [0.0, 378] mg/g. In adjusted models, increased TNFαR1 was associated with global Mod/Sev CI (odds ratio [95% confidence interval] = 1.40 [1.02, 1.93]; p = 0.04); low bicarbonate (CO2 <20 mEq/L) with Mod/Sev memory impairment (3.04 [1.09, 8.47]; p = 0.03), and each 10-mg/dL lower cholesterol was associated with Mod/Sev executive function/processing speed impairment (1.12 [1.02, 1.23]; p = 0.02). However, after adjustment for multiple comparisons, these associations were no longer significant nor were any other kidney-metabolic factors significant for any CI classification.

CONCLUSION

In exploratory analyses in a CKD population, three kidney-metabolic factors were associated with CI, but after adjustment for multiple comparisons, were no longer significant. Future studies in larger CKD populations are needed to assess these potential risk factors for CI.

Catheter-Associated Bloodstream Infections among Patients on Hemodialysis: Progress before and during the COVID-19 Pandemic

Measures implemented to prevent transmission of severe acute respiratory syndrome coronavirus 2 in outpatient dialysis facilities may also help to prevent catheter-associated bloodstream infections in patients receiving hemodialysis. We used United States Renal Data System data to examine rates of antibiotic administration within dialysis facilities and rates of hospital admission for catheter-associated bloodstream infection from March 2018 through November 2020, and rates of hospitalization for sepsis, to address overall changes in hospitalization during the coronavirus disease 2019 (COVID-19) pandemic. Using logistic regression, we estimated year-over-year adjusted odds ratios of these events in 3-month intervals. During the first 6 months of the pandemic, rates of antibiotic administration were between 20% and 21% lower, and rates of hospitalization for catheter-associated bloodstream infection were between 17% and 24% lower than during corresponding periods in 2019, without significant changes in rates of hospitalization for sepsis. However, rates of catheter-associated events also decreased between 2018 and 2019, driven by reductions in facilities operated by a large dialysis provider. These data suggest that significant reductions in catheter-associated infections occurred during the pandemic, superimposed on nonpandemic-related reductions in some facilities before the pandemic. Even after the pandemic, it may be prudent to continue some COVID-19 mitigation measures to prevent catheter-associated bloodstream infections.

Development and outcomes of hyperkalemia in hospitalized patients: potential implications for care

INTRODUCTION

While severe hyperkalemia is commonly encountered, its manifestation in hospitalized patients and related outcomes are unclear. We aimed to examine development of hyperkalemia in hospitalized patients and associated outcomes.

METHODS

Data from a county hospital electronic health record were used to assess all inpatient admissions, 2012-2016, for non-dialysis-dependent patients with ≥1 K value for development of hyperkalemia. Unadjusted odds ratios (ORs) were calculated for associations of the maximum K value with in-hospital mortality and adjusted ORs were calculated for death associated with hyperkalemia.

RESULTS

In 47,018 individual patient hospitalizations, 1.3% had a maximum K ≥6.0 mEq/L and 4.2% <3.5 mEq/L. Fifth and 95th percentiles for maximum K values were 3.5 and 5.3 mEq/L. For high-K patients with a prior K value, the mean (SD) of the immediate pre-maximum K value was 5.0 ± 1.0 mEq/L, and the mean difference in K values (immediate pre-maximum to maximum) was 1.5 ± 1.1 mEq/L; mean duration between these two K tests was 10.7 ± 14.9 hours. Compared with maximum K values 3.5 to 4.0 mEq/L, ORs for death were 37.1 (95% confidence intervals, 25.8-53.3) for K 6.0 to <6.5, 88.6 (56.8-138.2) for K ≥7.0, and 18.9 (4.3-82.2) for K <3.0 mEq/L. In adjusted models, the OR for death for K ≥6.0 mEq/L was 4.9 (3.7-6.4).

DISCUSSION/CONCLUSIONS

Peak K values ≥6.0 mEq/L were associated with mortality. Values tended to increase rapidly, limiting opportunities for detection and treatment. Systems-based approaches to detect life-threatening hyperkalemia should be studied.

Changes in Treatment of Patients with Incident ESKD during the Novel Coronavirus Disease 2019 Pandemic

BACKGROUND

The COVID-19 pandemic caused major disruptions to care for patients with advanced CKD.

METHODS

We investigated the incidence of documented ESKD, ESKD treatment modalities, changes in eGFR at dialysis initiation, and use of incident central venous catheters (CVCs) by epidemiologic week during the first half of 2020 compared with 2017-2019 historical trends, using Centers for Medicare and Medicaid Services data. We used Poisson and logistic regression for analyses of incidence and binary outcomes, respectively.

RESULTS

Incidence of documented ESKD dropped dramatically in 2020 compared with the expected incidence, particularly during epidemiologic weeks 15-18 (April, incidence rate ratio [IRR], 0.75; 95% CI, 0.73 to 0.78). The decrease was most pronounced for individuals aged ≥75 years (IRR, 0.69; 95% CI, 0.66 to 0.73). Pre-emptive kidney transplantation decreased markedly during weeks 15-18 (IRR, 0.56; 95% CI, 0.46 to 0.67). Mean eGFR at dialysis initiation decreased by 0.33 ml/min per 1.73 m2 in weeks 19-22; non-Hispanic Black patients exhibited the largest decrease, at 0.61 ml/min per 1.73 m2. The odds of initiating dialysis with eGFR <10 ml/min per 1.73 m2 were highest during weeks 19-22 (May, OR, 1.14; 95% CI, 1.05 to 1.17), corresponding to an absolute increase of 2.9%. The odds of initiating peritoneal dialysis (versus hemodialysis) were 24% higher (OR, 1.24; 95% CI, 1.14 to 1.34) in weeks 11-14, an absolute increase of 2.3%. Initiation with a CVC increased by 3.3% (OR, 1.30; 95% CI, 1.20 to 1.41).

CONCLUSIONS

During the first wave of the COVID-19 pandemic, the number of patients starting treatment for ESKD fell to a level not observed since 2011. Changes in documented ESKD incidence and other aspects of ESKD-related care may reflect differential access to care early in the pandemic.

Cinacalcet and gastrointestinal bleeding risk in patients receiving hemodialysis

PURPOSE

Secondary hyperparathyroidism (SHPT) is common among dialysis patients, and calcimimetics are a mainstay of treatment. This study assessed whether cinacalcet use is associated with gastrointestinal bleeding in a large hemodialysis cohort.

METHODS

A linked database of clinical records and medical claims for patients receiving hemodialysis in a large dialysis organization, 2007-2010, was used. A nested case-control study was performed among patients aged ≥18 years who had received hemodialysis for ≥90 days, had Medicare Parts A, B, and D coverage for ≥1 year, and had clinical evidence of SHPT (parathyroid hormone >300 pg/mL). Cases were those who experienced death or hospitalization caused by gastrointestinal bleeding. Each case was matched to up to four controls. Exposure was measured by any cinacalcet use, current use, past use, cumulative exposure days, and cumulative dosage. Conditional logistic models were used to assess the association.

RESULTS

Of 48 437 patients included, 2570 experienced gastrointestinal bleeding events (2498 non-fatal, 72 fatal), and 2465 (2397 non-fatal, 68 fatal) were matched to 9500 controls; 17.2% of cases and 15.8% of controls had cinacalcet exposure and 11.1% of both cases and controls had current use. The adjusted odds ratios (95% CI) of gastrointestinal bleeding for any use, current use, and past use of cinacalcet were 1.04 (0.91-1.19), 0.97 (0.83-1.13), and 1.22 (0.99-1.50), respectively, with no use as the reference.

CONCLUSION

The results do not suggest an elevated risk of gastrointestinal bleeding resulting in hospitalization or death for hemodialysis patients exposed to cinacalcet.

Risk of hyperkalemia from renin-angiotensin-aldosterone system inhibitors and factors associated with treatment discontinuities in a real-world population

BACKGROUND

Hyperkalemia rates in renin-angiotensin-aldosterone system (RAAS) inhibitor users, and factors associated with treatment interruptions and cessations, have not been explored in a large, population-wide database.

METHODS

RAAS inhibitor users were identified in the linked UK Clinical Practice Research Datalink-Hospital Episodes Statistics data set, 2009-15. Treatment interruptions (no active prescription followed by reappearance) and cessations were determined. Hyperkalemia (serum K+>5.5 mmol/L) rates were calculated and factors associated with interruptions and cessations modeled using time-varying Cox regression, including hyperkalemia (as a time-dependent variable).

RESULTS

Among 434 027 RAAS inhibitor users, the hyperkalemia rate was 1.30 (95% confidence interval 1.28-1.32) per 100 patient-years. Of 73.7% of patients who experienced off-treatment periods, 57.6% experienced interruption only, 7.5% cessation only and 8.6% both. Within 1 year of initiating RAAS inhibitor treatment, approximately one-third of the patients experienced interruption or cessation. Hazard ratios for patients with severe hyperkalemia were 1.10 (10.5-1.16) for interruptions and 3.37 (3.25-3.50) for cessation. Compared with no chronic kidney disease (CKD), risk of interruption was 1.20 (1.16-1.25) and 1.57 (1.44-1.72) for Stages 4 and 5, respectively, and of cessation was 2.20 (2.07-2.33) and 2.87 (2.56-3.22). Risk of interruption increased for patients with heart failure or diabetes [1.04 (1.02-1.05); 1.13 (1.12-1.14), respectively] but the risk of cessation decreased [0.85 (0.82-0.87); 0.92 (0.90-0.94)].

CONCLUSIONS

Risk of RAAS inhibitor interruption and cessation increased as CKD stage progressed. Efforts targeting reasons for interruptions and, especially, cessations, such as hyperkalemia prevention, could decrease off-treatment periods for patients who would otherwise benefit, such as those with CKD, heart failure or diabetes.

Development and Validation of a Transfusion Risk Score for Patients Receiving Maintenance Hemodialysis

BACKGROUND

In patients on dialysis with anemia, avoiding red blood cell transfusions is preferable. We sought to develop and validate a novel transfusion prediction risk score for patients receiving maintenance hemodialysis.

METHODS

This retrospective cohort study used United States Renal Data System data to create a model development cohort (patients who were point prevalent and on hemodialysis on November 1, 2012) and a validation cohort (patients who were point prevalent and on hemodialysis on August 1, 2013). We characterized comorbidity, inflammatory conditions, hospitalizations, anemia and anemia management, iron parameters, intravenous iron use, and vitamin D use during a 6-month baseline period to predict subsequent 3-month transfusion risk. We used logistic least absolute shrinkage and selection operator regression. In an exploratory analysis, model results were used to calculate a score to predict 6- and 12-month hospitalization and mortality.

RESULTS

Variables most predictive of transfusion were prior transfusion, hemoglobin, ferritin, and number of hospital days in the baseline period. The resulting c-statistic in the validation cohort was 0.74, indicating relatively good predictive power. The score was associated with a significantly increased risk of subsequent mortality (hazard ratios 1.0, 1.22, 1.26, 1.54, 1.71, grouped from lowest to highest score), but not with hospitalization.

CONCLUSIONS

We developed a transfusion prediction risk score with good performance characteristics that was associated with mortality. This score could be further developed into a clinically useful application, allowing clinicians to identify patients on hemodialysis most likely to benefit from a timely, proactive anemia treatment approach, with the goal of avoiding red blood cell transfusions and attendant risks of adverse clinical outcomes.

Initial Effects of COVID-19 on Patients with ESKD

BACKGROUND

Reports from around the world have indicated a fatality rate of patients with coronavirus disease 2019 (COVID-19) in the range of 20%-30% among patients with ESKD. Population-level effects of COVID-19 on patients with ESKD in the United States are uncertain.

METHODS

We identified patients with ESKD from Centers for Medicare and Medicaid Services data during epidemiologic weeks 3-27 of 2017-2020 and corresponding weeks of 2017-2019, stratifying them by kidney replacement therapy. Outcomes comprised hospitalization for COVID-19, all-cause death, and hospitalization for reasons other than COVID-19. We estimated adjusted relative rates (ARRs) of death and non-COVID-19 hospitalization during epidemiologic weeks 13-27 of 2020 (March 22 to July 4) versus corresponding weeks in 2017-2019.

RESULTS

Among patients on dialysis, the rate of COVID-19 hospitalization peaked between March 22 and April 25 2020. Non-Hispanic Black race and Hispanic ethnicity associated with higher rates of COVID-19 hospitalization, whereas peritoneal dialysis was associated with lower rates. During weeks 13-27, ARRs of death in 2020 versus 2017-2019 were 1.17 (95% confidence interval [95% CI], 1.16 to 1.19) and 1.30 (95% CI, 1.24 to 1.36) among patients undergoing dialysis or with a functioning transplant, respectively. Excess mortality was higher among non-Hispanic Black, Hispanic, and Asian patients. Among patients on dialysis, the rate of non-COVID-19 hospitalization during weeks 13-27 in 2020 was 17% lower versus hospitalization rates for corresponding weeks in 2017-2019.

CONCLUSIONS

During the first half of 2020, the clinical outcomes of patients with ESKD were greatly affected by COVID-19, and racial and ethnic disparities were apparent. These findings should be considered in prioritizing administration of COVID-19 vaccination.

Association of Dementia-Related Psychosis With Long-term Care Use and Death

OBJECTIVE

To determine the association of dementia-related psychosis (DRP) with death and use of long-term care (LTC); we hypothesized that DRP would be associated with increased risk of death and use of LTC in patients with dementia.

METHODS

A retrospective cohort study was performed. Medicare claims from 2008 to 2016 were used to define cohorts of patients with dementia and DRP. Outcomes were LTC, defined as nursing home stays of >100 consecutive days, and death. Patients with DRP were directly matched to patients with dementia without psychosis by age, sex, race, number of comorbid conditions, and dementia index year. Association of DRP with outcomes was evaluated using a Cox proportional hazard regression model.

RESULTS

We identified 256,408 patients with dementia. Within 2 years after the dementia index date, 13.9% of patients developed DRP and 31.9% had died. Corresponding estimates at 5 years were 25.5% and 64.0%. Mean age differed little between those who developed DRP (83.8 ± 7.9 years) and those who did not (83.1 ± 8.7 years). Patients with DRP were slightly more likely to be female (71.0% vs 68.3%) and white (85.7% vs 82.0%). Within 2 years of developing DRP, 16.1% entered LTC and 52.0% died; corresponding percentages for patients without DRP were 8.4% and 30.0%, respectively. In the matched cohort, DRP was associated with greater risk of LTC (hazard ratio [HR] 2.36, 2.29-2.44) and death (HR 2.06, 2.02-2.10).

CONCLUSIONS

DRP was associated with a more than doubling in the risk of death and a nearly 2.5-fold increase in risk of the need for LTC.

Testing Patterns for CKD-MBD Abnormalities in a Sample US Population

Introduction

Patterns of testing, treatment, and retesting following treatment for disorders of chronic kidney disease mineral bone disorder (CKD-MBD) have not been explored using a large electronic database.

Methods

To determine concordance with CKD-MBD management guidelines, we used 2010 to 2019 data from an electronic health record (>50 million patients) to create cohorts of incident CKD stage 3, 4, and 5 patients using diagnosis codes and estimated glomerular filtration rates. The CKD-MBD test ordering and relevant drug prescribing were assessed during follow-up. We estimated cumulative incidence of posttreatment retesting (death as competing risk). We used multivariable Cox regression to examine baseline characteristics and pretreatment test results as predictors of retesting.

Results

For 215,553 stage 3, 43,576 stage 4, and 11,407 stage 5 CKD patients, the mean follow-up was 2.3, 1.7, and 0.6 years, respectively. Only 46% of stage 4 and 41% of stage 5 patients underwent parathyroid hormone (PTH) testing, 74% and 73% had phosphorus testing, and 38% and 25% had 25D testing. By 1 year after vitamin D sterol treatment, only 50%, 53%, and 60% of stage 3, 4, and 5 patients had been retested for PTH. By 1 year after treatment with ergocalciferol or cholecalciferol, only 46%, 49%, and 55% had 25D reassessed. Pretreatment levels of PTH and 25D were not associated in a graded fashion with likelihood of retesting after treatment. Rates of retesting were not highest for patients with the highest and lowest pre-treatment PTH and 25D levels, respectively.

Conclusion

Frequency of testing for CKD-MBD abnormalities and posttreatment retesting appears to be suboptimal.

Outcomes Following Ischemic Stroke in Older Patients With CKD Stages 4 and 5: A Retrospective Cohort Study

RATIONALE & OBJECTIVE

The associations between ischemic stroke and time to dialysis initiation and/or death in adults with late-stage chronic kidney disease (CKD) have not been explored. We sought to measure the rate and factors associated with stroke in CKD stages 4 and 5 (CKD4-5) and assess the association of stroke with initiation of dialysis and death.

STUDY DESIGN

Retrospective cohort.

SETTING & PARTICIPANTS

Patients with CKD4-5 in Medicare 2007 to 2014.

EXPOSURE OR PREDICTOR

Ischemic stroke in CKD4-5.

OUTCOMES

Initiation of maintenance dialysis or death.

ANALYTICAL APPROACH

Cox proportional hazard modeling assessed factors associated with ischemic stroke. A matched analysis (stroke/no stroke) estimated the cumulative incidence of incident kidney failure and death, treated as competing events. Simulations using a state transition model determined differences in expected time to kidney failure or death and death alone for patients with and without stroke with CKD5.

RESULTS

123,251 patients with CKD4 and 22,054 with CKD5 were identified. Mean ages were 81.0 and 79.2 years, respectively. Female sex (HRs of 1.21 [95% CI, 1.12-1.31] and 1.39 [95% CI, 1.04-1.86] for CKD4 and CKD5, respectively) and black race (HRs of 1.25 [95% CI, 1.12-1.39] and 1.12 [95% CI, 0.80-1.58] for CKD4 and CKD5, respectively) were factors associated with ischemic stroke. Rates for 30-day mortality were 13.3% and 18.8%, and for 1-year mortality, 40.0% and 38.2%. For patients with CKD5, kidney failure or death occurred an average of 3.6 months sooner for patients with an ischemic stroke, and death (irrespective of kidney failure), a mean of 24.3 months sooner.

LIMITATIONS

Study design cannot determine causality; lack of data for stroke severity.

CONCLUSIONS

Female sex and black race were associated with increased risk for stroke in CKD4 and CKD5. In CKD5, stroke was associated with a shorter time to kidney failure or death by nearly 4 months, and to death, by more than 2 years.

Factors Associated with Elective Withdrawal of Maintenance Hemodialysis: A Case-Control Analysis

BACKGROUND

Associations of demographic factors with elective dialysis withdrawal and setting of death, patterns of illness trajectories preceding death, and how illness trajectories, particularly worsening putative disability, are associated with elective withdrawal are poorly understood.

METHODS

Using United States Renal Data System data, we performed a case-control analysis of hemodialysis patients who died in 2010-2015. A disability proxy score characterized disability; logistic regression identified characteristics associated with death from withdrawal and with death setting; and group-based trajectory models characterized the trajectory of disability in the months preceding death.

RESULTS

We identified 14,571 (9.2%) patients who withdrew and 144,305 (90.8%) who died of a non-withdrawal cause. Women were more likely than men to withdraw (OR 1.19, 95% CI 1.15-1.24). The most rural patients were more likely to withdraw than the most urban (OR 1.37, 95% CI 1.25-1.50). Medicaid coverage (a marker for impoverishment) was associated with less withdrawal (OR 0.90, 95% CI 0.86-0.94). Disability proxy score was strongly related to withdrawal: the OR for patients in the highest score category was 31.16 (95% CI 28.40-34.20) versus those with a score of 0. Women and whites (vs. blacks) were overrepresented in the worst, versus better, proxy disability score trajectory. In-hospital death and death in the intensive care unit were more common in women and minorities than in men and whites, but less common in the most rural patients.

CONCLUSIONS

Important differences separate patients who electively withdraw from those who die of non-withdrawal causes. Worsening disability, in particular, may be a marker for withdrawal.

Association of hospital transfusion use and infection-related rehospitalizations among patients receiving hemodialysis: A retrospective cohort study

INTRODUCTION

Red blood cell transfusions have been associated with infection risk. We investigated whether hospital transfusions are associated with infections in maintenance hemodialysis patients requiring transfusions for chronic anemia.

METHODS

In this retrospective cohort study, hemodialysis patients who experienced an incident hospitalization during 2012-2013 were identified from the Medicare end-stage renal disease database. Hospital transfusions were first categorized into one of five groups based on adjusted likelihood of administering red blood cell transfusions during inpatient hospital stays that occurred over the previous year (2011) among the general Medicare cohort. Next, in a patient-level analysis, patients were categorized according to transfusion use at the incident hospitalization hospital. Outcomes were infection-related rehospitalization and a composite of infection-related hospitalization and all-cause mortality during the 60 days following hospital discharge. We estimated adjusted rate ratios for the association between hospital transfusion use and risk of rehospitalization or the composite endpoint using Poisson regression models.

FINDINGS

The study included 1578 hospitals and 61,455 hemodialysis patients. Patient characteristics were balanced across hospital transfusion use groups. The overall transfusion rate was 16.0%. The overall 30-day infection-related hospitalization rate (95% confidence interval) per 100 patient-months was 8.8 (8.6-9.1); rates did not differ by transfusion use group. Rate ratios for infection-related rehospitalization were 1.00 (0.91-1.10) over 30 days and 0.98 (0.91-1.05) over 60 days comparing the lowest and highest transfusion use groups.

DISCUSSION

We found no differences in risk of infection-related rehospitalization for patients receiving maintenance hemodialysis across the varying blood transfusion rates of US hospitals.

Prevalence and incidence of systemic lupus erythematosus and associated outcomes in the 2009-2016 US Medicare population

OBJECTIVES

We aimed to update data on the prevalence and incidence of systemic lupus erythematosus (SLE) in the Medicare population and describe associated outcomes.

METHODS

This observational study used Medicare 20% random sample data 2007-2016 to estimate SLE prevalence and incidence 2009-2016. The study population included patients aged ≥18 years (stratified by <65 and ≥65 years) with Medicare fee-for-service coverage. The SLE definition was based on a published and validated algorithm. All-cause death, hospitalizations, and kidney disease incidence were defined for a prevalent SLE cohort 2011-2015. Unadjusted event rates during 5-year follow-up were reported per 100 patient-years.

RESULTS

The study included > 5 million eligible patients for each year 2009-2016. There were 19,518 (10,898, aged ≥65; 8620, aged <65) in 2016, extrapolated to 97,590 (54,490 aged ≥65; 43,100 aged <65) in the overall 2016 Medicare population. Age- and sex-adjusted prevalence rates (per 100,000 Medicare population) ranged from 301.1 in 2009 to 366.6 in 2016, all ages, and 184.0-239.9, ≥65 years. There were 2614 (1844 aged ≥65; 770 aged <65) incident patients in 2016; age-/sex-adjusted incidence rates (per 100,000 Medicare population) ranged from 46.9 in 2009 to 49.0 in 2016, all ages, and 37.5-40.8, ≥65. Five-year unadjusted mortality, elderly vs. younger, was 8.8 vs. 3.8, morbidity 34.5 vs. 32.4, and kidney disease incidence 19.8 vs. 18.0 per 100 patient-years.

CONCLUSIONS

Prevalence rates steadily increased while incidence was relatively stable 2009-2016. Our data should be interpreted with caution due to our elderly study population.

Association of diabetes-related kidney disease with cardiovascular and non-cardiovascular outcomes: a retrospective cohort study

BACKGROUND

Diabetes-related kidney disease is associated with end-stage renal disease and mortality, but opportunities remain to quantify its association with cardiovascular and non-cardiovascular morbidity outcomes.

METHODS

We used the Truven Health MarketScan Commercial Claims and Encounters Database, 2010-2014, which includes specific health services records for employees and their dependents from a selection of large employers, health plans, and government and public organizations. We used administrative claims data to quantify the association between diabetes-related kidney disease and end-stage renal disease, myocardial infarction, congestive heart failure, stroke, and infections. Cox proportional hazard regression models were used to estimate adjusted hazard ratios of developing complications.

RESULTS

Among 2.2 million patients with diabetes, 7.1% had diabetes-related kidney disease: 13.5%, stage 1-2; 33.8%, stage 3; 13.2% stages 4-5; 39.5%, unknown stage. In multivariable Cox proportional hazard models adjusted for demographic characteristics, baseline comorbid conditions, and total hospital days during the baseline period, hazard ratios for each outcome increased with greater diabetes-related kidney disease severity (stage 1-2 vs. stage 4-5) compared with no diabetes-related kidney disease: myocardial infarction, 1.2 (95% confidence interval 1.1-1.4) and 3.1 (2.9-3.4); congestive heart failure, 1.7 (1.6-1.9) and 5.6 (5.3-5.8); stroke, 1.3 (1.2-1.5) and 2.3 (2.1-2.5); infection, 1.4 (1.3-1.5) and 2.9 (2.8-3.0). Among patients with stage 4-5 disease, 36-month cumulative incidence was nearly 22.8% for congestive heart failure, and 25.8% for infections.

CONCLUSIONS

Diabetes-related kidney disease appears to be formally diagnosed at a more advanced stage than might be expected, given clinical practice guidelines. Risks of cardiovascular and non-cardiovascular outcomes are high.

Early withdrawal and non-withdrawal death in the months following hemodialysis initiation: A retrospective cohort analysis

INTRODUCTION

Whether and how factors associated with elective hemodialysis withdrawal differ from those associated with non-withdrawal death soon after maintenance hemodialysis initiation have not been well studied.

METHODS

A retrospective cohort analysis was performed using USRDS data from 2011 to 2014. Patients were randomly categorized 2:1 into training and validation samples. Elective withdrawal deaths were identified using the Death Notification form. Multinomial logistic regression was used to fit a prediction model for three outcome categories (withdrawal, non-withdrawal death, survival at 6 months) as a function of demographic, comorbidity, and functional status.

FINDINGS

The training sample comprised 80,284 hemodialysis patients. Mean age was 71.7 ± 11.4 years, 44.9% were female, 72.9% were white, and 22.8% were black. Within 6 months, 19.1% died, of whom 2099 (2.6%) withdrew and 13,223 (16.5%) died of a non-withdrawal cause; 13.7% of all deaths were withdrawals. Baseline characteristics and event rates were similar among the 40,142 patients in the validation sample. The model was calibrated adequately and could discriminate moderately well between withdrawal and survival (area under ROC curve [AUC]: 0.77) and between non-withdrawal death and survival (AUC: 0.73). However, discrimination between withdrawal and non-withdrawal death was relatively low (AUC: 0.62). Older age and white, compared with non-white, race were each associated with greater odds of death, and these associations were stronger for withdrawal than for non-withdrawal death.

DISCUSSION

Advanced age and white, as opposed to black, race were most strongly associated with early elective hemodialysis withdrawal compared with non-withdrawal death. However, it is difficult to differentiate between patients who will experience early withdrawal vs. non-withdrawal death, as many factors are similarly associated with both outcomes.

Adherence to Kidney Disease: Improving Global Outcomes Mineral and Bone Guidelines for Monitoring Biochemical Parameters

BACKGROUND

Mineral and bone disorder (MBD) is common in patients with chronic kidney disease (CKD), and is associated with risk of fractures, cardiovascular disease, and death. Kidney Disease: Improving Global Outcomes (KDIGO) guidelines recommend monitoring CKD-MBD biochemical markers, including parathyroid hormone (PTH), phosphorus, 25-hydroxyvitamin D (25D), calcium, and alkaline phosphatase (ALP), in patients with moderate-to-severe CKD.

METHODS

To determine guideline adherence, we used administrative claims records from the 20% sample of Medicare beneficiaries with Parts A, B, and D coverage, 2007 to 2015, and identified cohorts of patients with nondialysis stage 3, 4, or 5 CKD. Testing for biochemical markers during follow-up was defined based on laboratory procedure codes. Baseline factors associated with laboratory testing were determined using logistic regression. All analyses were performed separately by CKD stage.

RESULTS

A total of 640,946 stage 3, 136,278 stage 4, and 22,076 stage 5 CKD patients, 50.2-52.9% women, mean age 74.4-78.0 years, were followed for a mean of 2.5, 1.3, and 0.7 years respectively. The frequency of testing was low for PTH (35.2-48.2%), phosphorus (46.6-62.0%), and 25D (29.3-46.7%). Testing was somewhat higher for calcium (88.1-95.4%) and ALP (63.5-88.1%); most tests were features of larger panels (e.g., basic metabolic panel). Older age, most comorbid conditions, and lack of prior nephrology care were associated with lower likelihood of testing.

CONCLUSIONS

In fee-for-service Medicare beneficiaries, laboratory testing for CKD-MBD biochemical markers appears to be suboptimal in relation to KDIGO guidelines. Competing priories, such as management of comorbid disease and preparation for renal replacement therapy, may distract from CKD-MBD monitoring.

Relation of Race, Apparent Disability, and Stroke Risk With Warfarin Prescribing for Atrial Fibrillation in Patients Receiving Maintenance Hemodialysis

Little is known about how warfarin is prescribed for stroke prevention in maintenance dialysis patients with chronic atrial fibrillation (AF). We examined patterns of warfarin use, and associated factors, after AF diagnosis. This retrospective cohort analysis studied US Medicare patients receiving maintenance dialysis January 1, 2008, to June 30, 2010. Demographics, co-morbidity, and a durable medical equipment claims-based disability proxy score predicted warfarin prescription after AF diagnosis. The analysis included 8,964 patients with nonvalvular AF. Compared with nonusers, warfarin users were younger (age 65.4 ± 12.1 vs 67.0 ± 12.9 years) and more likely to be men (54.3% vs 52.8%) and of white race (64.0% vs 59.6%). After adjustment for other factors, nonwhite, versus white, race was associated with significantly less warfarin use within 30 days: odds ratios (ORs), 95% confidence intervals (CIs), were 0.80, 0.71 to 91, for black patients; 0.57, 0.43 to 0.76, for Asians; and 0.74, 0.49 to 1.12, for members of other races. Percentages of patients receiving warfarin decreased as Hypertension Abnormal renal and liver function Stroke-Bleeding Labile INR Elderly Drugs or alcohol (HAS-BLED) bleeding risk score increased (OR 0.82, 95% CI 0.73 to 0.92, HAS-BLED score 3 to 4 versus 2; 0.38, 0.26 to 0.57, score ≥ 5 vs 2). However, as CHA2DS2-Vasc stroke-risk score increased, warfarin use tended to decrease (OR 0.90, 95% CI 0.78 to 1.03, p = 0.13, CHA2DS2-Vasc score 4 versus 1 to 3; 0.69, 0.61 to 0.78, p < 0.0001, score 5 vs 1 to 3). In conclusion, providers appear to weigh bleeding risk more heavily than stroke-prevention potential when prescribing warfarin for maintenance dialysis patients. Racial minorities received warfarin substantially less often than whites, even after accounting for other factors.

Excess Deaths Attributable to Influenza-Like Illness in the ESRD Population

BACKGROUND

Morbidity and mortality vary seasonally. Timing and severity of influenza seasons contribute to those patterns, especially among vulnerable populations such as patients with ESRD. However, the extent to which influenza-like illness (ILI), a syndrome comprising a range of potentially serious respiratory tract infections, contributes to mortality in patients with ESRD has not been quantified.

METHODS

We used data from the Centers for Disease Control and Prevention (CDC) Outpatient Influenza-like Illness Surveillance Network and Centers for Medicare and Medicaid Services ESRD death data from 2000 to 2013. After addressing the increasing trend in deaths due to the growing prevalent ESRD population, we calculated quarterly relative mortality compared with average third-quarter (summer) death counts. We used linear regression models to assess the relationship between ILI data and mortality, separately for quarters 4 and 1 for each influenza season, and model parameter estimates to predict seasonal mortality counts and calculate excess ILI-associated deaths.

RESULTS

An estimated 1% absolute increase in quarterly ILI was associated with a 1.5% increase in relative mortality for quarter 4 and a 2.0% increase for quarter 1. The average number of annual deaths potentially attributable to ILI was substantial, about 1100 deaths per year.

CONCLUSIONS

We found an association between community ILI activity and seasonal variation in all-cause mortality in patients with ESRD, with ILI likely contributing to >1000 deaths annually. Surveillance efforts, such as timely reporting to the CDC of ILI activity within dialysis units during influenza season, may help focus attention on high-risk periods for this vulnerable population.

Predialysis anemia management and outcomes following dialysis initiation: A retrospective cohort analysis

Whether and how anemia treatment with erythropoiesis stimulating agents (ESAs) before hemodialysis initiation may be associated with lower mortality after dialysis initiation is unknown. We compared all-cause and cardiovascular mortality in two groups of patients who experienced distinct anemia treatment patterns with ESAs before and after hemodialysis initiation. This retrospective cohort analysis included patients initiating hemodialysis April 1, 2012-June 30, 2013, identified from United States Renal Data System end-stage renal disease (ESRD) and pre-ESRD files. Patients treated with ESAs before and after hemodialysis initiation who maintained Hb ≥ 9.0 g/dL throughout (comparator group, n = 3662) were compared with patients with Hb < 9.0 g/dL before hemodialysis initiation (with or without ESAs) whose levels increased with ESAs after hemodialysis initiation (referent group, n = 4461). Cox proportional hazards models were used to calculate the hazard ratio of all-cause and cardiovascular mortality after hemodialysis initiation. Of 20,454 patients, 4855 (23.7%) had Hb < 9.0 g/dL upon hemodialysis initiation; of these 4855, 26.6% received ESAs before initiation. Comparator group Hb levels increased from 8.2 ± 0.8 mg/dL upon initiation to 10.9 ± 1.2 with ESAs afterward. Comparator patients were more likely than referent patients to be younger (76.3 ± 6.7 versus 77.2 ± 6.9 years), male (51.5% versus 49.8%), and black (24.6% versus 18.6%). Risk of all-cause mortality was lower for the comparator group versus the referent group at 3 (HR 0.83, 95% CI 0.68–1.00, P = 0.052), 6 (0.86, 0.74–1.00, P = 0.047), and 12 (0.88, 0.78–0.99, P = 0.036) months. The pattern was similar for cardiovascular mortality. Hb ≥ 9.0 with ESAs before and after hemodialysis initiation was generally associated with lower post-initiation all-cause and cardiovascular mortality compared with predialysis Hb < 9.0 g/dL in patients whose Hb levels subsequently improved with ESAs after hemodialysis initiation.

Prevalence and Risk of Severe Cognitive Impairment in Advanced Chronic Kidney Disease

Background

Our primary goal is to describe the prevalence, severity, and risk of cognitive impairment (CI) by estimated glomerular filtration rate (eGFR, in mL/min/1.73 m2) in a cohort enriched for advanced chronic kidney disease (CKD; eGFR < 45), adjusting for albuminuria, as measured by urine albumin-to-creatinine ratio (UACR, in mg/g). As both eGFR and albuminuria are associated with CI risk in CKD, we also seek to determine the extent that eGFR remains a useful biomarker for risk of CI in those with CKD and concomitant albuminuria.

Methods

Chi-square tests measured the prevalence of severe CI and mild cognitive impairment (MCI) by eGFR level. Logistic regression models and generalized linear models measured risk of CI by eGFR, adjusted for UACR.

Results

Participants were 574 adults with a mean age of 69; 433 with CKD (eGFR < 60, nondialysis) and 141 controls (eGFR ≥ 60). Forty-eight percent of participants with CKD had severe CI or MCI. The prevalence of severe CI was highest (25%) in those with eGFR < 30. eGFR < 30 was only associated with severe CI in those without albuminuria (UACR < 30; OR = 3.3; p = .02) and was not associated with MCI in similar models.

Conclusions

One quarter of those with eGFR < 30 had severe CI. eGFR < 30 was associated with over threefold increased odds of severe CI in those with UACR < 30, but not with UACR > 30, suggesting that eGFR < 30 is a valid biomarker for increased risk of severe CI in those without concomitant albuminuria.

Readmissions Following a Hospitalization for Cardiovascular Events in Dialysis Patients: A Retrospective Cohort Study

Background

Hospitalization for cardiovascular disease (CVD) is common among patients receiving maintenance dialysis, but patterns of readmissions following cardiovascular events are underexplored.

Methods and Results

In this retrospective analysis of prevalent, Medicare‐eligible patients receiving dialysis in 2012–2013, all live‐discharge hospitalizations attributed to CVD were ascertained. Rates of all‐cause, CVD‐related, and non–CVD‐related readmissions and death in the ensuing 10 and 30 days were calculated. Multinomial logistic modeling was used to assess the relationship between potential explanatory factors and outcomes of interest. Among 142 210 analyzed hospitalizations, mean age at time of index CVD hospitalization was 64.9±14.1 years; 50.4% of index hospitalizations were for women, and 41.4% were for white patients. Fully 15.6% and 34.2% of CVD hospitalizations resulted in readmission within 10 and 30 days, respectively; less than half of readmissions were CVD related (42.5%, 10 days; 43.1%, 30 days). Death within 30 days, regardless of readmission, occurred after 4.5% of index hospitalizations; 51.2% were attributed to CVD. Compared with ages 65 to 69 years, younger age tended to be associated with increased readmission risk (adjusted relative risk for ages 18–44 years: 1.55; 95% confidence interval, 1.48–1.63). Readmission risk did not differ between white and black patients, but risk of death without readmission was markedly lower for black patients (relative risk: 0.60; 95% confidence interval, 0.55–0.67).

Conclusions

Roughly 1 in 3 CVD hospitalizations resulted in 30‐day readmission; nearly 1 in 20 was followed by death within 30 days. Risk of death without readmission was higher for white than black patients, despite no difference in risk of readmission.

Factors Associated With Withdrawal From Maintenance Dialysis: A Case-Control Analysis

BACKGROUND

Little is known about differences in the clinical course between patients receiving maintenance dialysis who do and do not withdraw from dialysis therapy.

STUDY DESIGN

Case-control analysis.

SETTING & PARTICIPANTS

US patients with Medicare coverage who received maintenance hemodialysis for 1 year or longer in 2008 through 2011.

PREDICTORS

Comorbid conditions, hospitalizations, skilled nursing facility stays, and a morbidity score based on durable medical equipment claims.

OUTCOME

Withdrawal from dialysis therapy.

MEASUREMENTS

Rates of medical events, hospitalizations, skilled nursing facility stays, and a morbidity score.

RESULTS

The analysis included 18,367 (7.7%) patients who withdrew and 220,443 (92.3%) who did not. Patients who withdrew were older (mean age, 75.3±11.5 [SD] vs 66.2±14.1 years) and more likely to be women and of white race, and had higher comorbid condition burdens. The odds of withdrawal among women were 7% (95% CI, 4%-11%) higher than among men. Compared to age 65 to 74 years, age 85 years or older was associated with higher adjusted odds of withdrawal (adjusted OR, 1.61; 95% CI, 1.54-1.68), and age 18 to 44 years with lower adjusted odds (adjusted OR, 0.36; 95% CI, 0.32-0.40). Blacks, Asians, and Hispanics were less likely to withdraw than whites (adjusted ORs of 0.36 [95% CI, 0.35-0.38], 0.47 [95% CI, 0.42-0.53], and 0.46 [95% CI, 0.44-0.49], respectively). A higher durable medical equipment claims-based morbidity score was associated with withdrawal, even after adjustment for traditional comorbid conditions and hospitalization; compared to a score of 0 (lowest presumed morbidity), adjusted ORs of withdrawal were 3.48 (95% CI, 3.29-3.67) for a score of 3 to 4 and 12.10 (95% CI, 11.37-12.87) for a score ≥7. Rates of medical events and institutionalization tended to increase in the months preceding withdrawal, as did morbidity score.

LIMITATIONS

Results may not be generalizable beyond US Medicare patients; people who withdrew less than 1 year after dialysis therapy initiation were not studied.

CONCLUSIONS

Women, older patients, and those of white race were more likely to withdraw from dialysis therapy. The period before withdrawal was characterized by higher rates of medical events and higher levels of morbidity.

Insights From the 2016 Peer Kidney Care Initiative Report: Still a Ways to Go to Improve Care for Dialysis Patients

Although outcomes improved during the past decade for patients receiving maintenance dialysis, gains were few in certain key areas, as highlighted in the 2016 Peer Kidney Care Initiative Report. Overall incidence rates of dialysis therapy initiation in adults remained relatively stable (∼42 per 100,000 US population, 2009-2013), but rates varied more than 2-fold, from 26 to 54, across US geographic regions. Hospitalization rates in incident patients decreased from 261 hospitalizations per 100 patient-years in 2003 to 207 in 2012, but observation stay rates increased from 40 to 67, attenuating the decline in hospitalizations by half. Decreases in prevalent patient hospitalizations for heart failure, from 15.6 per 100 patient-years in 2004 to 9.5 in 2013, were partially offset by increases in hospitalizations for volume overload, from 3.0 in 2004 to 6.1 in 2013. Prevalent patient rates of hospitalizations for arrhythmias (∼4.6 per 100 patient-years) did not improve during the past decade, whereas sudden cardiac death as a proportion of total cardiovascular deaths increased from 53% to 73%. Hospitalization rates for pneumonia/influenza, at about 8.3 per 100 patient-years in prevalent patients, did not decrease during this period, while hospitalization rates for bacteremia/sepsis increased from 8.6 to 12.0. If decreases in mortality rates are to be sustained, novel approaches to these challenges will be required.

Elevated intracranial pressure and reversible eye-tracking changes detected while viewing a film clip

OBJECTIVE The precise threshold differentiating normal and elevated intracranial pressure (ICP) is variable among individuals. In the context of several pathophysiological conditions, elevated ICP leads to abnormalities in global cerebral functioning and impacts the function of cranial nerves (CNs), either or both of which may contribute to ocular dysmotility. The purpose of this study was to assess the impact of elevated ICP on eye-tracking performed while patients were watching a short film clip. METHODS Awake patients requiring placement of an ICP monitor for clinical purposes underwent eye tracking while watching a 220-second continuously playing video moving around the perimeter of a viewing monitor. Pupil position was recorded at 500 Hz and metrics associated with each eye individually and both eyes together were calculated. Linear regression with generalized estimating equations was performed to test the association of eye-tracking metrics with changes in ICP. RESULTS Eye tracking was performed at ICP levels ranging from -3 to 30 mm Hg in 23 patients (12 women, 11 men, mean age 46.8 years) on 55 separate occasions. Eye-tracking measures correlating with CN function linearly decreased with increasing ICP (p < 0.001). Measures for CN VI were most prominently affected. The area under the curve (AUC) for eye-tracking metrics to discriminate between ICP < 12 and ≥ 12 mm Hg was 0.798. To discriminate an ICP < 15 from ≥ 15 mm Hg the AUC was 0.833, and to discriminate ICP < 20 from ≥ 20 mm Hg the AUC was 0.889. CONCLUSIONS Increasingly elevated ICP was associated with increasingly abnormal eye tracking detected while patients were watching a short film clip. These results suggest that eye tracking may be used as a noninvasive, automatable means to quantitate the physiological impact of elevated ICP, which has clinical application for assessment of shunt malfunction, pseudotumor cerebri, concussion, and prevention of second-impact syndrome.

Mammography screening and detection of early stage breast cancer in Hispanic and African American women at a Minnesota safety net healthcare system

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Background: Approximately 12% of breast cancer cases occur in women younger than 50 years, per SEER data from 2012. Hispanic women are known to present at a younger age and African American women with more advanced stage disease. In this study, we describe the impact of age and race on the initial presentation of breast cancer among minority women treated at the Hennepin Healthcare System (HHS) in the state of Minnesota. Methods: A single-institution retrospective analysis of data from our electronic health record of all breast cancer diagnoses from 2010-2015. Cases were compared by age ( < 50 or > 50 years), race (Caucasian, African American, Hispanic, other), stage (AJCC 7th edition), and method of diagnosis (self-reported mass or screening mammography). Results: A total of 315 breast cancer diagnoses occurred at HHS from 2010-2015. In our cohort, 29% of all breast cancer cases were diagnosed in women < 50yrs. Hispanic and African American women had higher rates of diagnosis at < 50yrs compared to Caucasian women (38.9% vs 37.1% vs 18.1 respectively, p < 0.05). Early stage cancer (stage 0 or I) accounted for most diagnoses in those > 50yrs (54.8%), while advanced stage (stage II-IV) was more prevalent in the < 50yrs age group (59.5%) (p < 0.05). Of all women diagnosed with breast cancer, 63% presented with a self-reported mass and 37% were diagnosed by screening mammography. Hispanics and African American women had a higher rate of presentation with a self-reported mass (74% and 66% respectively) compared to Caucasian women (55%). Women with breast cancer < 50yrs were more likely to present with a self-reported mass than women > 50yrs (80% vs 55%, p < 0.05). 92% of Hispanic and 80% of African American women < 50yrs presented with a self-reported mass, compared to 62% of Caucasian women (p = 0.095). Conclusions: At our institution, Hispanic and African American women are diagnosed at a significantly younger age than Caucasian women, and those diagnosed at a younger age have more advanced disease. Presenting with a self-reported mass is very common for young non-Caucasian women. Whether screening mammography can be better utilized to change these trends requires further study.

Use of the Medicare database in epidemiologic and health services research: a valuable source of real-world evidence on the older and disabled populations in the US

Medicare is the federal health insurance program for individuals in the US who are aged ≥65 years, select individuals with disabilities aged <65 years, and individuals with end-stage renal disease. The Centers for Medicare and Medicaid Services grants researchers access to Medicare administrative claims databases for epidemiologic and health outcomes research. The data cover beneficiaries’ encounters with the health care system and receipt of therapeutic interventions, including medications, procedures, and services. Medicare data have been used to describe patterns of morbidity and mortality, describe burden of disease, compare effectiveness of pharmacologic therapies, examine cost of care, evaluate the effects of provider practices on the delivery of care and patient outcomes, and explore the health impacts of important Medicare policy changes. Considering that the vast majority of US citizens ≥65 years of age have Medicare insurance, analyses of Medicare data are now essential for understanding the provision of health care among older individuals in the US and are critical for providing real-world evidence to guide decision makers. This review is designed to provide researchers with a summary of Medicare data, including the types of data that are captured, and how they may be used in epidemiologic and health outcomes research. We highlight strengths, limitations, and key considerations when designing a study using Medicare data. Additionally, we illustrate the potential impact that Centers for Medicare and Medicaid Services policy changes may have on data collection, coding, and ultimately on findings derived from the data.

Relative Incidence of Acute Adverse Events with Ferumoxytol Compared to Other Intravenous Iron Compounds: A Matched Cohort Study

Concerns persist about adverse reactions to intravenous (IV) iron. We aimed to determine the relative safety of ferumoxytol compared to other IV iron compounds. This retrospective cohort study with propensity-score matching for patients and drug doses used the Medicare 20% random sample to identify patients (1) without chronic kidney disease (non-CKD) and (2) with non-dialysis-dependent chronic kidney disease (NDD-CKD) who received a first dose of IV iron in 2010–2012. Exposures were ferumoxytol, iron sucrose, sodium ferric gluconate, or iron dextran. Outcomes were hypersensitivity symptoms, anaphylaxis, emergency department (ED) encounters, hospitalizations, and death after acute IV iron exposure. In the primary analysis for reactions on the day of or following exposure, there was no difference in hypersensitivity symptoms (hazard ratio 1.04, 95% confidence interval 0.94–1.16) or hypotension (0.83, 0.52–1.34) between 4289 non-CKD ferumoxytol users and an equal number of users of other compounds; results were similar for 7358 NDD-CKD patients and an equal number of controls. All-cause ED encounters or hospitalizations were less common in both the non-CKD (0.56, 0.45–0.70) and NDD-CKD ferumoxytol-treated patients (0.83, 0.71–0.95). Fewer than 10 deaths occurred in both the non-CKD and NDD-CKD ferumoxytol users and in matched controls; the hazard for death did not differ significantly between ferumoxytol users and controls in the non-CKD patients (2.00, 0.33–11.97) or in the NDD-CKD patients (0.25, 0.04–1.52). Multiple sensitivity analyses showed similar results. Ferumoxytol did not appear to be associated with more adverse reactions than other compounds for the treatment of iron-deficiency anemia in both non-CKD and NDD-CKD patients.

The Healthy People 2020 Objectives for Kidney Disease: How Far Have We Come, and Where Do We Need to Go?

The Healthy People 2020 initiative established goals for patients with CKD and ESRD. We assessed United States progress toward some of these key goals. Using data from the Centers for Medicare and Medicaid Services ESRD database, we created yearly cohorts of patients on incident and prevalent dialysis from 2000 to 2013. Change in event rate or proportion change over the study years was modeled using Poisson regression with adjustment for age, race, sex, and primary cause of ESRD. For all-cause mortality in prevalent patients, Healthy People 2020 sought approximately 0.8% relative annual improvement; actual improvement was 2.7%. Improvement was greatest for patients ages 18-44 years old (3.8%; P<0.01 versus 2.8% for ages 65-74 years old) and 2.3% even for patients ages ≥75 years old. For mortality in incident patients, the relative annual decrease was 2.1% overall, a twofold improvement over the goal; mortality decreased nearly twice as much in black as in white patients (3.2% versus 1.8%; P<0.001). Geographic variation was substantial; the relative annual decrease was 0.6% in the Midwest and more than fourfold greater (2.7%) in the South. Cardiovascular mortality in prevalent patients decreased dramatically at 5.0% per year, far exceeding the annual goal of approximately 0.8%; the decrease was greatest in patients ages ≥75 years old (5.5%; P<0.001 versus ages 65-74 years old; 5.1%). The relative annual increase in percentages of patients with a fistula at dialysis initiation was 2.4%, roughly three times the goal; the increase was greater for black than white patients (3.2% versus 2.3%; P<0.01). Adjusted regional differences varied greater than twofold: 2.0% for the South versus 4.1% for the Midwest. Thus, although gains have been substantial, not all groups have benefitted equally. Goal development for Healthy People 2030 should consider changes in goal paradigms, such as tailoring by geographic region and incorporating patient-centered goals.

Facility-level CKD-MBD composite score and risk of adverse clinical outcomes among patients on hemodialysis

BACKGROUND

Patients receiving hemodialysis with values outside of target levels for parathyroid hormone (PTH: 150-600 pg/mL), calcium (Ca: 8.4-10.2 mg/dL), and phosphate (P: 3.5-5.5 mg/dL) are at elevated morbidity and mortality risk. We examined whether patients receiving care in dialysis facilities where greater proportions of patients have at least two values out of target have a higher risk of adverse clinical outcomes.

METHODS

The study cohort consisted of 39,085 prevalent hemodialysis patients in 1298 DaVita dialysis facilities as of September 1, 2009, followed from January 1, 2010, until an outcome, a censoring event, or December 31, 2010. We determined the quintile of the distribution across facilities of the proportion of patients with at least two of three parameters out of, or above, target over a 4-month baseline period. The primary composite outcome was cardiovascular hospitalization or death. Secondary outcomes included death, cardiovascular hospitalization, and parathyroidectomy. Poisson regression models were used to estimate the association of facility quintile with outcomes.

RESULTS

Facility quintile was associated with a 7 % increased risk of cardiovascular hospitalization or death (quintile 5 versus 1, RR 1.07, 95 % CI 1.01-1.13) using the out-of-target measure of exposure and a 12 % increased risk (RR 1.12, 95 % CI 1.06-1.19) using the above-target measure. No association was seen for death using either measure. Patients in facility quintiles 3-5 (versus 1) were at increased parathyroidectomy risk (RR ranged from 2.05, 95 % CI 1.10-3.82, for quintile 3 to 2.73, 95 % CI 1.50-4.98, for quintile 5).

CONCLUSIONS

Facility level analysis of a large prevalent sample of US patients on hemodialysis demonstrates that patients in facilities with the least control of PTH, Ca, and P had the greatest risk of parathyroidectomy or the combination of cardiovascular hospitalization or death.