Nursing Home Status Adjustment for Standardized Mortality and Hospitalization in Dialysis Facility Reports.

Rationale & Objective: Compared to the original nursing home status (any nursing home stay in the previous calendar year), new nursing home status variables were developed to improve the risk adjustment of Standardized Mortality/Hospitalization Ratio (SMR/SHR) models used in public reporting of dialysis quality of care, such as the Annual Dialysis Facility Report. Study Design: Retrospective observational study. Setting & Participants: 625,040 US maintenance dialysis patients with >90 kidney failure days in 2019. Predictors: Nursing home status variables; patient characteristics; comorbid conditions. Outcomes: Mortality/hospitalization. Analytical Approach: We assigned patients and patient times (SMR/SHR model) to one of 3 mutually exclusive categories: long-term care (≥90 days), short-term care (1-89 days), or non-nursing home, based on nursing home stay during the previous 365 days from the first day of the time period at risk. Nursing home status was derived from the Nursing Home Minimum Data Set. Comparisons of hazard ratios from adjusted models, facility SMR/SHR performance, and model C-statistics between the original/new models were performed. Results: SMR's hazard ratio of original nursing home status (2.09) was lower than both ratios of short-term care (2.38) and long-term care (2.43), whereas SHR's hazard ratio of original nursing home status (1.10) was between the ratios of long-term care (1.01) and short-term care (1.20). There was a difference in hazard ratios between short-term care and long-term care for both measures. Small percentages of facilities changed performance categories: 0.7% for SMR and 0.4% for SHR. The SMR C-statistic improved whereas the SHR C-statistic was relatively unchanged. Limitations: Limited capture of subacute rehabilitation stays in the nursing home by using a 90-day cutoff for short-term care and long-term care; unable to draw causal inference about nursing home care. Conclusions: Use of a nursing home metric that effectively separates short-term from long-term nursing home utilization results in more meaningful risk adjustment that generally comports with Medicare payment policy, potentially resulting in more interpretable results for dialysis stakeholders.

COVID-19 and Hospitalization Among Maintenance Dialysis Patients: A Retrospective Cohort Study Using Time-Dependent Modeling.

Rationale & Objective: The coronavirus disease 2019 (COVID-19) pandemic has had a profound impact on hospitalizations in general and on dialysis patients in particular. This study modeled the impact of COVID-19 on hospitalizations of dialysis patients in 2020. Study Design: Retrospective cohort study. Setting & Participants: Medicare patients on dialysis in calendar year 2020. Predictors: COVID-19 status was divided into 4 stages: COVID1 (first 10 days after initial diagnosis), COVID2 (extends until the Post-COVID stage), Post-COVID (after 21 days with no COVID-19 diagnosis), and Late-COVID (begins after a hospitalization with a COVID-19 diagnosis); demographic and clinical characteristics; and dialysis facilities. Outcome: The sequence of hospitalization events. Analytical Approach: A proportional rate model with a nonparametric baseline rate function of calendar time on the study population. Results: A total of 509,609 patients were included in the study, 63,521 were observed to have a SARS-CoV-2 infection, 34,375 became Post-COVID, and 1,900 became Late-COVID. Compared with No-COVID, all 4 stages had significantly greater adjusted risks of hospitalizations with relative rates of 18.50 (95% CI, 18.19-18.81) for COVID1, 2.03 (95% CI, 1.99-2.08) for COVID2, 1.37 (95% CI, 1.35-1.40) for Post-COVID, and 2.00 (95% CI, 1.89-2.11) for Late-COVID. Limitations: For Medicare Advantage patients, we only had inpatient claim information. The analysis was based on data from the year 2020, and the effects may have changed due to vaccinations, new treatments, and new variants. The COVID-19 effects may be somewhat overestimated due to missing information on patients with few or no symptoms and possible delay in COVID-19 diagnosis. Conclusions: We discovered a marked time dependence in the effect of COVID-19 on hospitalization of dialysis patients, beginning with an extremely high risk for a relatively short period, with more moderate but continuing elevated risks later, and never returning to the No-COVID level.

The Impact of COVID-19 on Postdischarge Outcomes for Dialysis Patients in the United States: Evidence from Medicare Claims Data.

Background: Recent investigations have shown that, on average, patients hospitalized with coronavirus disease 2019 (COVID-19) have a poorer postdischarge prognosis than those hospitalized without COVID-19, but this effect remains unclear among patients with end-stage kidney disease (ESKD) who are on dialysis. Methods: Leveraging a national ESKD patient claims database administered by the US Centers for Medicare and Medicaid Services, we conducted a retrospective cohort study that characterized the effects of in-hospital COVID-19 on all-cause unplanned readmission and death within 30 days of discharge for patients on dialysis. Included in this study were 436,745 live acute-care hospital discharges of 222,154 Medicare beneficiaries on dialysis from 7871 Medicare-certified dialysis facilities between January 1 and October 31, 2020. Adjusting for patient demographics, clinical characteristics, and prevalent comorbidities, we fit facility-stratified Cox cause-specific hazard models with two interval-specific (1-7 and 8-30 days after hospital discharge) effects of in-hospital COVID-19 and effects of prehospitalization COVID-19. Results: The hazard ratios due to in-hospital COVID-19 over the first 7 days after discharge were 95% CI, 1.53 to 1.65 for readmission and 95% CI, 1.38 to 1.70 for death, both with P<0.001. For the remaining 23 days, the hazard ratios were 95% CI, 0.89 to 0.96 and 95% CI, 0.86 to 1.07, with P<0.001 and P=0.50, respectively. Effects of prehospitalization COVID-19 were mostly nonsignificant. Conclusions: In-hospital COVID-19 had an adverse effect on both postdischarge readmission and death over the first week. With the surviving patients having COVID-19 substantially selected from those hospitalized, in-hospital COVID-19 was associated with lower rates of readmission and death starting from the second week.

COVID-19 Risk Factors and Mortality Outcomes Among Medicare Patients Receiving Long-term Dialysis.

Importance: There is a need for studies to evaluate the risk factors for COVID-19 and mortality among the entire Medicare long-term dialysis population using Medicare claims data. Objective: To identify risk factors associated with COVID-19 and mortality in Medicare patients undergoing long-term dialysis. Design, Setting, and Participants: This retrospective, claims-based cohort study compared mortality trends of patients receiving long-term dialysis in 2020 with previous years (2013-2019) and fit Cox regression models to identify risk factors for contracting COVID-19 and postdiagnosis mortality. The cohort included the national population of Medicare patients receiving long-term dialysis in 2020, derived from clinical and administrative databases. COVID-19 was identified through Medicare claims sources. Data were analyzed on May 17, 2021. Main Outcomes and Measures: The 2 main outcomes were COVID-19 and all-cause mortality. Associations of claims-based risk factors with COVID-19 and mortality were investigated prediagnosis and postdiagnosis. Results: Among a total of 498 169 Medicare patients undergoing dialysis (median [IQR] age, 66 [56-74] years; 215 935 [43.1%] women and 283 227 [56.9%] men), 60 090 (12.1%) had COVID-19, among whom 15 612 patients (26.0%) died. COVID-19 rates were significantly higher among Black (21 787 of 165 830 patients [13.1%]) and Hispanic (13 530 of 86 871 patients [15.6%]) patients compared with non-Black patients (38 303 of 332 339 [11.5%]), as well as patients with short (ie, 1-89 days; 7738 of 55 184 patients [14.0%]) and extended (ie, ≥90 days; 10 737 of 30 196 patients [35.6%]) nursing home stays in the prior year. Adjusting for all other risk factors, residing in a nursing home 1 to 89 days in the prior year was associated with a higher hazard for COVID-19 (hazard ratio [HR] vs 0 days, 1.60; 95% CI 1.56-1.65) and for postdiagnosis mortality (HR, 1.31; 95% CI, 1.25-1.37), as was residing in a nursing home for an extended stay (COVID-19: HR, 4.48; 95% CI, 4.37-4.59; mortality: HR, 1.12; 95% CI, 1.07-1.16). Black race (HR vs non-Black: HR, 1.25; 95% CI, 1.23-1.28) and Hispanic ethnicity (HR vs non-Hispanic: HR, 1.68; 95% CI, 1.64-1.72) were associated with significantly higher hazards of COVID-19. Although home dialysis was associated with lower COVID-19 rates (HR, 0.77; 95% CI, 0.75-0.80), it was associated with higher mortality (HR, 1.18; 95% CI, 1.11-1.25). Conclusions and Relevance: These results shed light on COVID-19 risk factors and outcomes among Medicare patients receiving long-term chronic dialysis and could inform policy decisions to mitigate the significant extra burden of COVID-19 and death in this population.

Acute Kidney Injury Requiring Dialysis and Incident Dialysis Patient Outcomes in US Outpatient Dialysis Facilities.

BACKGROUND AND OBJECTIVES: About 30% of patients with AKI may require ongoing dialysis in the outpatient setting after hospital discharge. A 2017 Centers for Medicare & Medicaid Services policy change allows Medicare beneficiaries with AKI requiring dialysis to receive outpatient treatment in dialysis facilities. Outcomes for these patients have not been reported. We compare patient characteristics and mortality among patients with AKI requiring dialysis and patients without AKI requiring incident dialysis. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: We used a retrospective cohort design with 2017 Medicare claims to follow outpatients with AKI requiring dialysis and patients without AKI requiring incident dialysis up to 365 days. Outcomes are unadjusted and adjusted mortality using Kaplan-Meier estimation for unadjusted survival probability, Poisson regression for monthly mortality, and Cox proportional hazards modeling for adjusted mortality. RESULTS: In total, 10,821 of 401,973 (3%) Medicare patients requiring dialysis had at least one AKI claim, and 52,626 patients were Medicare patients without AKI requiring incident dialysis. Patients with AKI requiring dialysis were more likely to be White (76% versus 70%), non-Hispanic (92% versus 87%), and age 60 or older (82% versus 72%) compared with patients without AKI requiring incident dialysis. Unadjusted mortality was markedly higher for patients with AKI requiring dialysis compared with patients without AKI requiring incident dialysis. Adjusted mortality differences between both cohorts persisted through month 4 of the follow-up period (all P=0.01), then, they declined and were no longer statistically significant. Adjusted monthly mortality stratified by Black and other race between patients with AKI requiring dialysis and patients without AKI requiring incident dialysis was lower throughout month 4 (1.5 versus 0.60, 1.20 versus 0.84, 1.00 versus 0.80, and 0.95 versus 0.74; all P<0.001), which persisted through month 7. Overall adjusted mortality risk was 22% higher for patients with AKI requiring dialysis (1.22; 95% confidence interval, 1.17 to 1.27). CONCLUSIONS: In fully adjusted analyses, patients with AKI requiring dialysis had higher early mortality compared with patients without AKI requiring incident dialysis, but these differences declined after several months. Differences were also observed by age, race, and ethnicity within both patient cohorts.

Characteristics of Markets and Patients Served by ESRD Seamless Care Organizations.

Under the Comprehensive End-stage Renal Disease (ESRD) Care (CEC) Model, dialysis facilities and nephrologists form ESRD Seamless Care Organizations (ESCOs) to deliver high value care. This study compared the characteristics of patients and markets served and unserved by CEC and assessed its generalizability. ESCOs operated in 65 of 384 markets. ESCO markets were larger than non-ESCO markets, had fewer White patients, higher household income, and higher Medicare spending per patient. Patients in ESCOs were similar to eligible nonaligned patients in age and sex but differed in race/ethnicity and were more often treated in an urban area; comorbidity prevalence differed modestly. CEC is available to a meaningful share of the dialysis population and relatively few dialysis patients resided in a market where no provider could meet the participation threshold, so market size may not be the primary barrier for potential new participants in CEC or future kidney care models.

Comparative effectiveness analysis of Medicare dialysis facility survey processes.

BACKGROUND: To assure and improve the quality and safety of care provided by dialysis facilities, federal oversight has been conducted through periodic survey assessment. However, with the growing number of individuals living with ESRD and dialysis facilities, state survey agencies have faced challenges in time and resources to complete survey activities. Therefore, the survey process ('Basic Survey' used prior to 2013) was redesigned in order to develop a more efficient process ('Core Survey' newly implemented since 2013). The purpose of this analysis was to evaluate and compare dialysis facility survey outcomes between the Core and Basic Survey processes, using a causal inference technique. The survey outcomes included condition-level citations, total citations (condition- and standard-level), and citation rate per survey-hour. METHODS: For comparisons of non-randomly assigned survey types, propensity score matching was used. Data were drawn from CMS' Quality Improvement Evaluation System (QIES) database from January 1, 2013 through July 31, 2014. Covariates available included survey type, facility characteristics (state, urban, practices catheter reuse, dialysis modalities offered, number of patients, mortality, hospitalization, infection) and survey-related characteristics (number of surveyors, time since last survey). RESULTS: Compared to the Basic Survey, the Core Survey identified 10% more total citations (P = 0.001) and identified condition-level citations more frequently, although the latter finding did not reach statistical significance. These findings suggest an increase of 10% in citation rate (i.e. ratio between citations and survey time) with the Core survey process (P = 0.002). CONCLUSIONS: Greater efficiency has implications for attenuating the time-intensive burden of the state survey process, and improving the safety and quality of care provided by dialysis facilities.

Paying for Frequent Dialysis.

In late 2017, the 7 regional contractors responsible for paying dialysis claims in Medicare proposed new payment rules that would restrict payment for hemodialysis treatments in excess of 3 weekly to exceptional acute-care circumstances. Frequent hemodialysis is performed more frequently than the traditional thrice-weekly pattern, and many stakeholders-patients, providers, dialysis machine manufacturers, and others-have expressed concern that these payment rules will inhibit the growth of this treatment modality's use among US dialysis patients. In this Perspective, we explain the role of these contractors in the context of Medicare's in-center hemodialysis-centric dialysis payment system and assess how well this system accommodates the higher treatment frequencies of both peritoneal dialysis and frequent hemodialysis. Then, given the available evidence concerning the relative effectiveness of these modalities versus thrice-weekly in-center hemodialysis and trends in their use, we discuss options for modifying Medicare's payment system to support frequent dialysis.

Persistent Variation in Medicare Payment Authorization for Home Hemodialysis Treatments.

OBJECTIVE: To analyze variation in medical care use attributable to Medicare's decentralized claims adjudication process as exemplified in home hemodialysis (HHD) therapy. DATA SOURCES/STUDY SETTING: Secondary data analysis using 2009-2012 paid Medicare claims for HHD and in-center hemodialysis (IHD). STUDY DESIGN: We compared variation across Medicare administrative contractors (MACs) in predicted paid treatments per standardized patient-month for HHD and IHD patients. We used ordinary least-squares regression to determine whether higher paid HHD treatment counts expanded HHD programs' presence among dialysis facilities. DATA COLLECTION: We identified HHD and IHD treatments using procedure, revenue center, and claim condition codes on type 72x claims. PRINCIPAL FINDINGS: MACs varied persistently in predicted HHD treatments per patient-month, ranging from 14.3 to 21.9 treatments versus 10.9 to 12.4 IHD treatments. The presence of facilities' HHD programs was uncorrelated with average HHD payment counts. CONCLUSIONS: Medicare's claims adjudication process promotes variation in medical care use, as we observe among HHD patients. MACs' discretionary decision making, while potentially facilitating innovation, may admit inefficiency in care practice as well as inequitable access to health care services. Regulators should weigh the benefits of flexibility in local coverage decisions against those of national standards for medical necessity.

Variation in infection prevention practices in dialysis facilities: results from the national opportunity to improve infection control in ESRD (End-Stage Renal Disease) project.

OBJECTIVE To observe patient care across hemodialysis facilities enrolled in the National Opportunity to Improve Infection Control in ESRD (end-stage renal disease) (NOTICE) project in order to evaluate adherence to evidence-based practices aimed at prevention of infection. SETTING AND PARTICIPANTS Thirty-four hemodialysis facilities were randomly selected from among 772 facilities in 4 end-stage renal disease participating networks. Facility selection was stratified on dialysis organization affiliation, size, socioeconomic status, and urban/rural status. MEASUREMENTS Trained infection control evaluators used an infection control worksheet to observe 73 distinct infection control practices at the hemodialysis facilities, from October 1, 2011, through January 31, 2012. RESULTS There was considerable variation in infection control practices across enrolled facilities. Overall adherence to recommended practices was 68% (range, 45%-92%) across all facilities. Overall adherence to expected hand hygiene practice was 72% (range, 10%-100%). Compliance to hand hygiene before and after procedures was high; however, during procedures hand hygiene compliance averaged 58%. Use of chlorhexidine as the specific agent for exit site care was 19% overall but varied from 0% to 35% by facility type. The 8 checklists varied in the frequency of perfect performance from 0% for meeting every item on the checklist for disinfection practices to 22% on the arteriovenous access practices at initiation. CONCLUSIONS Our findings suggest that there are many areas for improvement in hand hygiene and other infection prevention practices in end-stage renal disease. These NOTICE project findings will help inform the development of a larger quality improvement initiative at dialysis facilities.

Correlation of clinical disease severity to radiographic thumb osteoarthritis index.

PURPOSE: To determine if a slight modification of the 1987 Eaton-Glickel staging and interpreting 4 standardized radiographs for trapeziometacarpal (TMC) osteoarthritis (OA) improved analysis, to determine if a quantifiable index measurement from a single Robert (pronated anteroposterior) view enhanced reproducibility, and to examine whether improved radiographic staging correlated to clinically relevant disease and thus support validity. METHODS: We analyzed 4 thumb radiographs (posteroanterior, lateral, Robert, and stress views) in 60 consecutive subjects representing an adult population spectrum of asymptomatic to advanced disease. Two experienced hand surgeons (A.L.L. and A.P.C.W.), 1 chief resident (A.J.B.), and 1 medical student (J.M.M.) performed the analysis on each subject's radiographs. We analyzed all 4 radiographs for Eaton and modified Eaton staging and then later analyzed only the Robert view for the thumb osteoarthritis (ThOA) index measurement. The radiographs were randomized and reread a week later for each classification at separate times. Surgically excised trapeziums from 20/60 subjects were inspected for first metacarpal surface disease and correlated to the 3 classifications. RESULTS: All 3 staging classifications demonstrated high reproducibility, with the intraclass correlation coefficient averaging 0.73 for the Eaton, 0.83 for the modified Eaton, and 0.95 for the ThOA index. Articular wear and metacarpal surface eburnation correlated highest to the ThOA index, with advanced disease 1.55 or greater correlating to Eaton III/IV and modified Eaton stage 3/4 in a linear relationship. CONCLUSIONS: The ThOA index based on a Robert view provided a measurable alternative to Eaton staging and correlated to severity of surgically relevant thumb TMC OA. CLINICAL RELEVANCE: A simple reproducible radiographic measurement may enhance TMC OA classification and provide a reliable means to predict clinical disease. TYPE OF STUDY/LEVEL OF EVIDENCE: Diagnostic II.

Blood transfusion practices in dialysis patients in a dynamic regulatory environment.

BACKGROUND: In 2011, Medicare implemented a prospective payment system (PPS) covering an expanded bundle of services that excluded blood transfusions. This led to concern about inappropriate substitution of transfusions for other anemia management methods. STUDY DESIGN: Medicare claims were used to calculate transfusion rates among dialysis patients pre- and post-PPS. Linear probability regressions adjusted transfusion trends for patient characteristics. SETTING & PARTICIPANTS: Dialysis patients for whom Medicare was the primary payer between 2008 and 2012. PREDICTOR: Pre-PPS (2008-2010) versus post-PPS (2011-2012). OUTCOMES & MEASUREMENTS: Monthly and annual probability of receiving one or more blood transfusions. RESULTS: Monthly rates of one or more transfusions varied from 3.8%-4.8% and tended to be lowest in 2010. Annual rates of transfusion events per patient were -10% higher in relative terms post-PPS, but the absolute magnitude of the increase was modest (-0.05 events/patient). A larger proportion received 4 or more transfusions (3.3% in 2011 and 2012 vs 2.7%-2.8% in prior years). Controlling for patient characteristics, the monthly probability of receiving a transfusion was significantly higher post-PPS (ß = 0.0034; P < 0.001), representing an -7% relative increase. Transfusions were more likely for females and patients with more comorbid conditions and less likely for blacks both pre- and post-PPS. LIMITATIONS: Possible underidentification of transfusions in the Medicare claims, particularly in the inpatient setting. Also, we do not observe which patients might be appropriate candidates for kidney transplantation. CONCLUSIONS: Transfusion rates increased post-PPS, but these increases were modest in both absolute and relative terms. The largest increase occurred for patients already receiving several transfusions. Although these findings may reduce concerns regarding the impact of Medicare's PPS on inappropriate transfusions that impair access to kidney transplantation or stress blood bank resources, transfusions should continue to be monitored.

Prevention of peritonitis in peritoneal dialysis.

Reducing the frequency of peritonitis for patients undergoing peritoneal dialysis (PD) continues to be a challenge. This review focuses on recent updates in catheter care and other patient factors that influence infection rates. An experienced nursing staff plays an important role in teaching proper PD technique to new patients, but nursing staff must be cognizant of each patient's unique educational needs. Over time, many patients become less adherent to proper dialysis technique, such as washing hands or wearing a mask. This behavior is associated with higher risk of peritonitis and is modifiable with re-training. Prophylactic antibiotics before PD catheter placement can decrease the infection risk immediately after catheter placement. In addition, some studies suggest that prophylaxis against fungal superinfection after antibiotic exposure is effective in reducing fungal peritonitis, although larger randomized studies are needed before this practice can be recommended for all patients. Over time, exit site and nasal colonization with pathogenic organisms can lead to exit-site infections and peritonitis. For patients with Staphylococcus aureus colonization, exit-site prophylaxis with either mupirocin or gentamicin cream reduces clinical infection with this organism. Although there are limited data for support, antibiotic prophylaxis before gastrointestinal, gynecologic, or dental procedures may also help reduce the risk of peritonitis.

Dialysis dose scaled to body surface area and size-adjusted, sex-specific patient mortality.

BACKGROUND AND OBJECTIVES: When hemodialysis dose is scaled to body water (V), women typically receive a greater dose than men, but their survival is not better given a similar dose. This study sought to determine whether rescaling dose to body surface area (SA) might reveal different associations among dose, sex, and mortality. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Single-pool Kt/V (spKt/V), equilibrated Kt/V, and standard Kt/V (stdKt/V) were computed using urea kinetic modeling on a prevalent cohort of 7229 patients undergoing thrice-weekly hemodialysis. Data were obtained from the Centers for Medicare & Medicaid Services 2008 ESRD Clinical Performance Measures Project. SA-normalized stdKt/V (SAN-stdKt/V) was calculated as stdKt/V × ratio of anthropometric volume to SA/17.5. Patients were grouped into sex-specific dose quintiles (reference: quintile 1 for men). Adjusted hazard ratios (HRs) for 1-year mortality were calculated using Cox regression. RESULTS: spKt/V was higher in women (1.7 ± 0.3) than in men (1.5 ± 0.2; P<0.001), but SAN-stdKt/V was lower (women: 2.3 ± 0.2; men: 2.5 ± 0.3; P<0.001). For both sexes, mortality decreased as spKt/V increased, until spKt/V was 1.6-1.7 (quintile 4 for men: HR, 0.62; quintile 3 for women: HR, 0.64); no benefit was observed with higher spKt/V. HR for mortality decreased further at higher SAN-stdKt/V in both sexes (quintile 5 for men: HR, 0.69; quintile 5 for women: HR, 0.60). CONCLUSIONS: SA-based dialysis dose results in dose-mortality relationships substantially different from those with volume-based dosing. SAN-stdKt/V analyses suggest women may be relatively underdosed when treated by V-based dosing. SAN-stdKt/V as a measure for dialysis dose may warrant further study.

Using race as a case-mix adjustment factor in a renal dialysis payment system: potential and pitfalls.

BACKGROUND: Racial disparities in health care are widespread in the United States. Identifying contributing factors may improve care for underserved minorities. To the extent that differential utilization of services, based on need or biological effect, contributes to outcome disparities, prospective payment systems may require inclusion of race to minimize these adverse effects. This research determines whether costs associated with end-stage renal disease (ESRD) care varied by race and whether this variance affected payments to dialysis facilities. STUDY DESIGN: We compared the classification of race across Medicare databases and investigated differences in cost of care for long-term dialysis patients by race. SETTING & PARTICIPANTS: Medicare ESRD database including 890,776 patient-years in 2004-2006. PREDICTORS: Patient race and ethnicity. OUTCOMES: Costs associated with ESRD care and estimated payments to dialysis facilities under a prospective payment system. RESULTS: There were inconsistencies in race and ethnicity classification; however, there was significant agreement for classification of black and nonblack race across databases. In predictive models evaluating the cost of outpatient dialysis care for Medicare patients, race is a significant predictor of cost, particularly for cost of separately billed injectable medications used in dialysis. Overall, black patients had 9% higher costs than nonblack patients. In a model that did not adjust for race, other patient characteristics accounted for only 31% of this difference. LIMITATIONS: Lack of information about biological causes of the link between race and cost. CONCLUSIONS: There is a significant racial difference in the cost of providing dialysis care that is not accounted for by other factors that may be used to adjust payments. This difference has the potential to affect the delivery of care to certain populations. Of note, inclusion of race into a prospective payment system will require better understanding of biological differences in bone and anemia outcomes, as well as effects of inclusion on self-reported race.

Do resource utilization and clinical measures still vary across dialysis chains after controlling for the local practices of facilities and physicians?

BACKGROUND: Because of adverse survival effects, anemia management and financial incentives to increase doses of erythropoiesis-stimulating agents (ESAs) have been controversial. Prior studies showed more aggressive anemia management in dialysis facilities owned by for-profit chains, but have been criticized for not accounting for practices of individual physicians and facilities. OBJECTIVE: To improve understanding of how dialysis practices and resource utilization are influenced by physicians, facilities, and chains. DESIGN: Mixed models with chain fixed effects and facility and physician random effects. SETTING: Medicare hemodialysis patients in 2004. PARTICIPANTS: A total of 234,158 patients, 3995 facilities, 4838 physicians, and 7 chain classifications were included. MEASUREMENTS: Spending per session for dialysis-related services billed separately from the dialysis treatment and for ESAs. Achievement of hematocrit (HCT) and urea reduction ratio (URR) targets. RESULTS: Of the 4 largest for-profit chains, 3 had higher resource use than independents, with differences up to $17.92 higher ESA/session. Utilization was positively associated with achieving target HCT. Despite incurring lower costs, patients treated by a large nonprofit chain were as likely as patients of independents to achieve the HCT target. The largest chains were more likely than independents to achieve the URR target. Substantial variation occurred across physicians and facilities, and adjustment for chain only modestly decreased this variation. LIMITATION: Chains' methods of influencing practices were not directly observed. CONCLUSIONS: Chains appear to have the ability to implement protocols that shift practices, but not the ability to substantially reduce local variation. Assertions that chain effects found by earlier studies were spurious are not supported.

When payment systems collide: the effect of hospitalization on anemia in renal dialysis patients.

BACKGROUND: Different types of providers often face differing financial incentives for providing similar types of care. This may have implications for payment systems that target improvements in care requiring multiple types of providers. OBJECTIVES: The objective of this study was to determine how hospitalization influences the anemia of Medicare patients with chronic renal failure, where anemia is treated under a prospective payment system during hospitalizations and under a fee-for-service system during outpatient renal dialysis. METHODS: We examined the effects of time in hospital and reason for hospitalization on levels of anemia among 87,263 Medicare renal dialysis patients with a hospital stay of 3 days or more during 2004. Medicare claims were used to measure changes in hematocrit between the month before and the month after hospital discharge, and to classify admissions with a high risk of anemia. Multilevel models were used to study variation in outcomes across providers. RESULTS: Longer time in the hospital was associated with worsening anemia. As expected, larger declines in hematocrit occurred following admissions for conditions or procedures with a high risk of anemia. However, we observed a similar effect of time in the hospital for admissions both with and without a high risk of anemia. There were relatively large differences in anemia outcomes across both individual hospitals and physicians. CONCLUSIONS: Hospitalization-related anemia increases the need for care by outpatient renal dialysis providers. Efforts to improve care through payment system design are more likely to be successful if financial incentives are aligned across care settings.

Provider monitoring and pay-for-performance when multiple providers affect outcomes: An application to renal dialysis.

OBJECTIVE: To characterize the influence of dialysis facilities and nephrologists on resource use and patient outcomes in the dialysis population and to illustrate how such information can be used to inform payment system design. DATA SOURCES: Medicare claims for all hemodialysis patients for whom Medicare was the primary payer in 2004, combined with the Medicare Enrollment Database and the CMS Medical Evidence Form (CMS Form 2728), which is completed at onset of renal replacement therapy. STUDY DESIGN: Resource use (mainly drugs and laboratory tests) per dialysis session and two clinical outcomes (achieving targets for anemia management and dose of dialysis) were modeled at the patient level with random effects for nephrologist and dialysis facility, controlling for patient characteristics. RESULTS: For each measure, both the physician and the facility had significant effects. However, facilities were more influential than physicians, as measured by the standard deviation of the random effects. CONCLUSIONS: The success of tools such as P4P and provider profiling relies upon the identification of providers most able to enhance efficiency and quality. This paper demonstrates a method for determining the extent to which variation in health care costs and quality of care can be attributed to physicians and institutional providers. Because variation in quality and cost attributable to facilities is consistently larger than that attributable to physicians, if provider profiling or financial incentives are targeted to only one type of provider, the facility appears to be the appropriate locus.

Association of quarterly average achieved hematocrit with mortality in dialysis patients: a time-dependent comorbidity-adjusted model.

BACKGROUND: Recent publications suggest that increased mortality is associated with high hematocrit targets in erythropoietin-stimulating agent-treated patients with chronic kidney disease. We aim to further inform the debate about optimal hematocrit targets, advancing the hypothesis that the current hematocrit target may not optimize the survival of patients with end-stage renal disease. STUDY DESIGN: Cross-sectional observational study. SETTING & PARTICIPANTS: Medicare dialysis patients from 2002 to 2004 (n = 393,967). FACTORS: Quarterly average hematocrit and erythropoietin alfa (EPO) dose. OUTCOMES: Mortality hazard ratios from time-dependent Cox proportional hazard models, adjusting for comorbidities. RESULTS: N = 2,712,197 patient-facility quarters. During the study, 100,086 deaths were identified. Percentages of patient quarters within each hematocrit category: hematocrit less than 27% (2.0%), 27% to 28.49% (1.7%), 28.5% to 29.9% (2.9%), 30% to 31.49% (5.2%), 31.5% to 32.99% (9.0%), 33% to 34.49% (14.9%), 34.5% to 35.99% (19.2%), 36% to 37.49% (18.0%), 37.5% to 38.99% (12.0%), 39% to 40.49% (6.4%), 40.5% to 41.99% (3.0%), and 42% or greater (3.1%). Mortality hazard ratios from the fully adjusted model: hematocrit less than 27% (3.11), 27% to 28.49% (2.60), 28.5% to 29.9% (2.14), 30% to 31.49% (1.80), 31.5% to 32.99% (1.44), 33% to 34.49% (1.17), 34.5% to 35.99% (reference), 36% to 37.49% (0.98), 37.5% to 38.99% (1.01), 39% to 40.49% (1.13), 40.5% to 41.99% (1.32), and 42% or greater (1.57). LIMITATIONS: First, potential confounding by indication related to associations between underlying illness and mortality, anemia, and EPO responsiveness. Second, Medicare claims data reflect a range of conditions and degrees of severity not easily translated into the clinical context. Third, for Medicare claims, EPO reporting is not required if EPO is not billed. Greater than 95% of "missing hematocrit" quarters are "EPO = 0" patient quarters. Interpretation of results for the missing hematocrit and EPO = 0 use categories is complicated by data source limitations. CONCLUSIONS: We show an association between mortality and low hematocrit in dialysis patients, in part reflecting the presence of comorbidities. We also show an association between increased mortality and high hematocrit. Additional interventional trials should be undertaken to better define the optimal target for anemia management in patients with end-stage renal disease, with careful prospective identification of underlying comorbidities and clinical factors contributing to high erythropoietin-stimulating agent requirement.

Size of the embryoid body influences chondrogenesis of mouse embryonic stem cells.

For applications in tissue engineering and regenerative medicine, embryonic stem cells (ESCs) are commonly pre-differentiated in the form of embryoid bodies (EBs). The uncontrolled cell differentiation in EBs results in a highly heterogeneous cell population, an unfavourable condition for therapeutic development. The purpose of this study was to determine an optimal size of EBs for chondrogenic differentiation. EBs were produced in suspension culture with mouse ESCs (ES-D3 GL). The 5-day-old EBs were sorted under a microscope by diameter: small EBs (S-EBs, < 100 microm), medium EBs (M-EBs, 100-150 microm) and large EBs (L-EBs, > 150 microm). The three sizes of EBs were cultured separately for 3 weeks in chondrogenic medium. Type II collagen and aggrecan gene expression was significantly upregulated in the S-EBs, when compared with the M-EBs and L-EBs (p < 0.05 and p < 0.001, respectively). Proteoglycans produced by the cells derived from S-EBs were > 50% of the other two groups. In addition, both Oct4 and Sox2 were expressed more in S-EBs than in M-EBs and L-EBs. Type X collagen expression was relatively increased in L-EBs. Slight shifts toward haematopoietic and endothelial differentiation were seen in the L- and M-EBs. In summary, the size of EBs has implications on ESC differentiation. Cells derived from S-EBs have a greater chondrogenic potential than those from M-EBs and L-EBs. The size of EBs can be a parameter utilized to optimize ESC differentiation for tissue engineering.