Organizational Status of Dialysis Facilities and Patient Outcome: Does Higher Injectable Medication Use Mediate Increased Mortality?

Objective

Examine the mediating effect of injectable drugs in the relationship between dialysis facility organizational status and patient mortality.

Study Setting

Medicare dialysis population.

Study Design

Data from the U.S. Renal Data System (USRDS) were used to identify 3,884 freestanding dialysis facilities and 37,942 Medicare patients incident to end-stage renal disease (ESRD) in 2006. The role of injectable medications was evaluated during a 2-year follow-up period by mediational analyses using mixed-effect regression models.

Data Collection

USRDS data were matched with Dialysis Facility Report data from Centers for Medicare and Medicaid Services (CMS) and census data.

Principal Findings

There was a strong association found between organizational status and use of injectable drugs. Large for-profit chains used significantly higher injectable medications compared with nonprofit chains and independent facilities. However, the relationship between facility organizational status and patient mortality was not found to be mediated through the higher use of injectable drugs.

Conclusions

Large for-profit chain facilities administered higher IV epoetin, iron, and vitamin D dosages, but this did not result in improved survival. Given the associated costs and lack of a survival benefit, the overuse of injectable medications among the U.S. dialysis patients will likely end under the recent bundling of injectable medications without jeopardizing patient outcomes.     

Reexploring Differences among For-Profit and Nonprofit Dialysis Providers

Objective. To determine whether profit status is associated with differences in hospital days per patient, an outcome that may also be influenced by provider financial goals. Data Sources. United States Renal Data System Standard Analysis Files and Centers for Medicare and Medicaid Services cost reports. Design. We compared the number of hospital days per patient per year across for‐profit and nonprofit dialysis facilities during 2003. To address possible referral bias in the assignment of patients to dialysis facilities, we used an instrumental variable regression method and adjusted for selected patient‐specific factors, facility characteristics such as size and chain affiliation, as well as metrics of market competition. Data Extraction Methods. All patients who received in‐center hemodialysis at any time in 2003 and for whom Medicare was the primary payer were included (N=170,130; roughly two‐thirds of the U.S. hemodialysis population). Patients dialyzed at hospital‐based facilities and patients with no dialysis facilities within 30 miles of their residence were excluded. Results. Overall, adjusted hospital days per patient were 17±5 percent lower in nonprofit facilities. The difference between nonprofit and for‐profit facilities persisted with the correction for referral bias. There was no association between hospital days per patient per year and chain affiliation, but larger facilities had inferior outcomes (facilities with 73 or more patients had a 14±1.7 percent increase in hospital days relative to facilities with 35 or fewer patients). Differences in outcomes among for‐profit and nonprofit facilities translated to 1,600 patient‐years in hospital that could be averted each year if the hospital utilization rates in for‐profit facilities were to decrease to the level of their nonprofit counterparts. Conclusions. Hospital days per patient‐year were statistically and clinically significantly lower among nonprofit dialysis providers. These findings suggest that the indirect incentives in Medicare's current payment system may provide insufficient incentive for for‐profit providers to achieve optimal patient outcomes.     

The effect of dialysis chains on mortality among patients receiving hemodialysis

Objective. To examine the association between dialysis facility chain affiliation and patient mortality. Study Setting. Medicare dialysis population. Study Design. Data from the United States Renal Data System (USRDS) were used to identify 3,601 free‐standing dialysis facilities and 34,914 Medicare patients' incidence to end‐stage renal disease (ESRD) in 2004. Mixed‐effect regression models were used to estimate patient mortality by dialysis facility chain and profit status during the 2‐year follow‐up. Data Collection. USRDS data were matched with facility, cost, and census data. Principle Findings. Of the five largest dialysis chains, the lowest mortality risk was observed among patients dialyzed at nonprofit (NP) Chain 5 facilities. Compared with Chain 5, hazard ratios were 19 percent higher (95 percent CI 1.06–1.34) and 24 percent higher (95 percent CI 1.10–1.40) for patients dialyzed at for‐profit (FP) Chain 1 and Chain 2 facilities, respectively. In addition, patients at FP facilities had a 13 percent higher risk of mortality than those in NP facilities (95 percent CI 1.06–1.22). Conclusions. Large chain affiliation is an independent risk factor for ESRD mortality in the United States. Given the movement toward further consolidation of large FP chains, reasons behind the increase in mortality require scrutiny.     

Profit-seeking, corporate control, and the trustworthiness of health care organizations: assessments of health plan performance by their affiliated physicians

OBJECTIVE: To compare the relative trustworthiness of nonprofit and for-profit health plans, using physician assessments to measure dimensions of plan performance that are difficult for consumers to evaluate. DATA SOURCE: A nationally representative sample of 1,621 physicians who responded to a special topics module of the 1998 Socioeconomic Monitoring System Survey (SMS), fielded by the American Medical Association. Physicians assessed various aspects of their primary managed care plan, defined as the plan in which they had the largest number of patients. STUDY DESIGN: Plan ownership was measured as the interaction of tax-exempt status (nonprofit versus for-profit) and corporate control (single state versus multistate health plans). Two sets of regression models are estimated. The dependent variables in the regressions are five measures of performance related to plan trustworthiness: two related to deceptive practices and three to dimensions of quality that are largely hidden from enrollees. The first set (baseline) models relate plan ownership to trustworthy practices, controlling for other characteristics of the plan, the marketplace for health insurance, and the physician respondents. The second (interactive) set of models examines how the magnitude of ownership-related differences in trustworthiness varies with the market share of nonprofit plans in each community. DATA COLLECTION: The 1998 SMS was fielded between April and September of 1998 by Westat Inc. The average time required for a completed interview was approximately 30 minutes. The overall response rate was 52.2 percent. PRINCIPAL FINDINGS: Compared with more local nonprofit plans, for-profit plans affiliated with multistate corporations are consistently reported by their affiliated physicians to engage in practices associated with reduced trustworthiness. Nonprofit plans affiliated with multistate corporations have more physician-reported practices associated with trustworthiness than do for-profit corporate plans on four of five outcomes, but appear less trustworthy than locally controlled nonprofits on two of the five measures. The magnitude of these ownership-related differences declines as the market share of nonprofit plans rises: for two of the five measures, ownership-related differences in practices related to trustworthiness are entirely eliminated when the nonprofits enroll more than 30 percent of the local market. CONCLUSIONS: The combination of for-profit ownership and multistate corporate control appears to consistently and substantially reduce physician-reported measures related to the trustworthiness of health plans. Because this is the fastest growing form of managed care, these results raise concerns about further erosion of trust in American health care. Preserving a substantial market niche for nonprofit plans appears to reduce this erosion and should be considered by policymakers as a strategy for restoring trust in the health care system.     

Mortality benefit of transfer to level I versus level II trauma centers for head-injured patients

OBJECTIVE: To determine whether head-injured patients transferred to level I trauma centers have reduced mortality relative to transfers to level II trauma centers. DATA SOURCE/STUDY SETTING: Retrospective cohort study of 542 patients with head injury who initially presented to 1 of 31 rural trauma centers in Oregon and Washington, and were transferred from the emergency department to 1 of 15 level I or level II trauma centers, between 1991 and 1994. STUDY DESIGN: A bivariate probit, instrumental variables model was used to estimate the effect of transfer to level I versus level II trauma centers on 30-day postdischarge mortality. Independent variables included age, gender, Injury Severity Scale (ISS), other indicators of injury severity, and a dichotomous variable indicating transfer to a level I trauma center. The differential distance between the nearest level I and level II trauma centers was used as an instrument. PRINCIPAL FINDINGS: Patients transferred to level I trauma centers differ in unmeasured ways from patients transferred to level II trauma centers, biasing estimates based on standard statistical methods. Transfer to a level I trauma center reduced absolute mortality risk by 10.1% (95% confidence interval 0.3%, 22.2%) compared with transfer to level II trauma centers. CONCLUSIONS: Patients with severe head injuries transferred from rural trauma centers to level I centers are likely to have improved survival relative to transfer to level II centers.     

The comparative performance of for-profit and nonprofit home health care services in the US

OBJECTIVE: To determine, by way of an exhaustive, systematic, and comprehensive review and summary of all scientific published studies, whether or not there are any performance differences between private for-profit and private nonprofit home health care providers. The second objective is to discover the proportion of all research on this topic that is devoted to home health care services compared to all other health services providers. DATA SOURCES: Computerized bibliographic searches of relevant databases and published indexes and abstracts were undertaken. They included Medline (Ovid and Pubmed versions), Web of Science (Social Sciences Citation Index and Science Citation Index), ABI/Inform, and Sociological Abstracts. Follow-up searches of reference lists in each article obtained from the computerized search were then completed. STUDY DESIGN: This systematic review retained for analysis all published studies that compared the performance of for-profit and nonprofit health care providers on access, quality, cost/efficiency, and/or amount of charity care, based on data collected after 1980. As a quality control measure only studies published in peer reviewed journals were included. Studies were coded according to the article's stated conclusions: for-profit superiority, nonprofit superiority, or no difference/mixed results. PRINCIPAL FINDINGS: The comparative performance of for-profit and nonprofit home health service organizations is one of the most understudied areas of health care provider services in the US today. Only 6 of the over 1030 comparisons of the two concerned home health care. No data on this topic have been collected since 1991, and no articles about it have been published in a peer-reviewed journal since 1995. CONCLUSION: Research on the relative performance of for-profit and nonprofit home health care services is a research priority urgently in need of attention.     

The production of dialysis by for-profit versus not-for-profit freestanding renal dialysis facilities.

OBJECTIVE. A study was conducted to determine whether for-profit and not-for-profit freestanding renal dialysis facilities differ with respect to efficiency in the production of dialysis treatments. DATA SOURCES/STUDY SETTING. National data on 1,224 Medicare-certified freestanding dialysis facilities were obtained from the Health Care Financing Administration's (HCFA) 1990 Independent Renal Dialysis Facility Cost Report. Data on Medicare patients receiving care at these facilities during 1990 were obtained from HCFA's End Stage Renal Disease (ESRD) Program Management and Medical Information System (PMMIS). STUDY DESIGN. Ordinary least squares regression (OLS) was used to estimate the association between monthly output of dialysis treatments in 1990 and (a) facility capital and labor inputs, (b) facility ownership characteristics, and (c) case-mix characteristics. DATA COLLECTION/EXTRACTION METHODS. Facility and patient level data were extracted from the Facility Cost Report and the PMMIS databases, respectively. Patient level data were aggregated by facility and merged with facility level data. PRINCIPAL FINDINGS. For-profit sole proprietorships, for-profit partnerships and for-profit corporations each produced significantly more dialysis treatments per month than not-for-profits, adjusting for quantities of resource inputs and case-mix characteristics. CONCLUSION. For-profit facilities appear to be more efficient producers of dialysis treatments than not-for-profits. Further study should address whether other factors such as differences in severity of disease or in quality of care are responsible for these observations.     

A national study of efficiency for dialysis centers: an examination of market competition and facility characteristics for production of multiple dialysis outputs

OBJECTIVE: To examine market competition and facility characteristics that can be related to technical efficiency in the production of multiple dialysis outputs from the perspective of the industrial organization model. STUDY SETTING: Freestanding dialysis facilities that operated in 1997 submitted cost report fonns to the Health Care Financing Administration (HCFA), and offered all three outputs--outpatient dialysis, dialysis training, and home program dialysis. DATA SOURCES: The Independent Renal Facility Cost Report Data file (IRFCRD) from HCFA was utilized to obtain information on output and input variables and market and facility features for 791 multiple-output facilities. Information regarding population characteristics was obtained from the Area Resources File. STUDY DESIGN: Cross-sectional data for the year 1997 were utilized to obtain facility-specific technical efficiency scores estimated through Data Envelopment Analysis (DEA). A binary variable of efficiency status was then regressed against its market and facility characteristics and control factors in a multivariate logistic regression analysis. PRINCIPAL FINDINGS: The majority of the facilities in the sample are functioning technically inefficiently. Neither the intensity of market competition nor a policy of dialyzer reuse has a significant effect on the facilities' efficiency. Technical efficiency is significantly associated, however, with type of ownership, with the interaction between the market concentration of for-profits and ownership type, and with affiliations with chains of different sizes. Nonprofit and government-owned Facilities are more likely than their for-profit counterparts to become inefficient producers of renal dialysis outputs. On the other hand, that relationship between ownership form and efficiency is reversed as the market concentration of for-profits in a given market increases. Facilities that are members of large chains are more likely to be technically inefficient. CONCLUSIONS: Facilities do not appear to benefit from joint production of a variety of dialysis outputs, which may explain the ongoing tendency toward single-output production. Ownership form does make a positive difference in production efficiency, but only in local markets where competition exists between nonprofit and for-profit facilities. The increasing inefficiency associated with membership in large chains suggests that the growing consolidation in the dialysis industry may not, in fact, be the strategy for attaining more technical efficiency in the production of multiple dialysis outputs.     

Survival of hemodialysis patients: modeling differences in risk of dialysis centers.

OBJECTIVE: Dialysis is the most common renal replacement therapy for patients with end stage renal disease. This paper considers survival of dialysis patients, aiming to assess quality of renal replacement therapy at dialysis centers in Rio de Janeiro, Brazil, and to investigate differences in survival between health facilities. METHODS: A Cox proportional hazards model, allowing for time-varying covariates and prevalent data, was the basic method used to analyze the survival of 11,579 patients on hemodialysis in 67 health facilities in Rio de Janeiro State from January 1998 until August 2001, using data obtained from routine information systems. A frailty random effects model was applied to investigate differences in mortality between health centers not explained by measured characteristics. RESULTS: The individual variables associated with the outcome were age and underlying disease, with diabetes being the main isolated risk factor. Considering covariates of the health unit, two factors were associated with performance: bigger units had on average better survival times than smaller ones and units which offered cyclic peritoneal dialysis performed less well than those that did not. There were significant frailty effects among centers, with relative risks varying between 0.24 and 3.15, and an estimated variance of 0.43. CONCLUSIONS: Routine assessment based on health registries of the outcome of any high technology medical treatment is extremely important in maintaining quality of care and in estimating the impact of changes in therapies, units, and patient profiles. The frailty model allowed estimation of variation in risk between centers not attributable to any measured covariates. This can be used to guide more specific investigation and changes in health policies related to renal transplant therapies.     

Factors affecting conversion rates to Medicaid among new admissions to nursing homes.

OBJECTIVE. This study examines conversion to Medicaid as a payment source among a cohort of newly admitted nursing home residents. DATA SOURCE. The longitudinal data used came from regular assessments of residents in the National Health Corporation's 43 for-profit nursing homes in Missouri, Kentucky, South Carolina, and Tennessee. This information system tracked all residents who were discharged, providing a comprehensive record that may have spanned multiple admissions. STUDY DESIGN. Using survival analysis methods, Cox regression, and survival trees, we contrasted the effect of state, initial payment source, education, age, and functional status on the rate of spend-down to Medicaid. DATA EXTRACTION METHODS. New-admission cohorts were created by linking an admission record for a newly admitted resident with all subsequent assessments and follow-up records to ascertain the precise dates of any payment source changes and other discharge transitions. PRINCIPAL FINDINGS. For the 1,849 individuals who were admitted as self-payers and who were still in the nursing home at the end of one year, there is a 19 percent probability of converting to Medicaid. All analytic methods revealed that education, age, and state of residence were predictive of spend-down among residents who were admitted as self-payers. CONCLUSIONS. Our results confirm the effect of education as an SES indicator and state as a proxy for Medicaid policy on spend-down. Future research should model the effects and duration of intervening hospitalizations and other transitions on Medicaid spend-down among new admissions.