Managed care and preventable hospitalization among Medicaid adults

OBJECTIVE: The study examines the association between managed care enrollment and preventable hospitalization patterns of adult Medicaid enrollees hospitalized in four states. DATA SOURCES/STUDY SETTING: Hospital discharge data from the Healthcare Cost and Utilization Project (HCUP) database of the Agency for Healthcare Research and Quality (AHRQ) for New York (NY), Pennsylvania (PA), Wisconsin (WI), and Tennessee (TN) residents in the age group 20-64 hospitalized in those states, linked to the Area Resource File (ARF) and American Hospital Association (AHA) survey files for 1997. STUDY DESIGN: The study uses separate logistic models for each state comparing preventable admissions with marker admissions (urgent, insensitive to primary care). The model controls for socioeconomic and demographic variables, and severity of illness. PRINCIPAL FINDINGS: Consistently in different states, private health maintenance organization (HMO) enrollment was associated with fewer preventable admissions than marker admissions, compared to private fee-for-service (FFS). However, Medicaid managed care enrollment was not associated with a reduction in preventable admissions, compared to Medicaid FFS. CONCLUSIONS: Our analysis suggests that the preventable hospitalization pattern for private HMO enrollees differs significantly from that for commercial FFS enrollees. However, little difference is found between Medicaid HMO enrollees and Medicaid FFS patients. The findings did not vary by the level of Medicaid managed care penetration in the study states.     

Including hospice in Medicare capitation payments: would it save money?

Hospice services received by Medicare risk-based health maintenance organization (HMO) enrollees are paid on a non-capitated basis, creating financial incentives for HMOs to encourage their terminally ill patients to elect hospice. Using Medicare administrative records for 1998, we found that hospice enrollment in the last month of life was significantly higher among HMO enrollees than among beneficiaries in fee-for-service (FFS). However, low mortality rates among HMO enrollees produced similar population-based rates of hospice use in the HMO and FFS sectors. Simulations showed that including hospice care under capitation payments in July 1998 would have produced very small savings for Medicare.     

Prostate cancer treatment and ten-year survival among group/staff HMO and fee-for-service Medicare patients.

OBJECTIVE: To compare treatment patterns and the ten-year survival of prostate cancer patients in two large, nonprofit, group/staff HMOs to those of patients receiving care in the fee-for-service health setting. DATA SOURCES/STUDY DESIGN: A cohort of men age 65 and over diagnosed with prostate cancer between 1985 and the end of 1992 and followed through 1994. Subjects (n = 21,741) were ascertained by two population-based tumor registries covering the greater San Francisco-Oakland and Seattle-Puget Sound areas. Linkage of registry data with Medicare claims data and with HMO inpatient utilization data allowed the determination of health plan enrollment and the measurement of comorbid conditions. Multivariate regression models were used to examine HMO versus FFS treatment and survival differences adjusting for sociodemographic and clinical characteristics. PRINCIPAL FINDINGS: Among cases with non-metastatic prostate cancer, HMO patients were more likely than FFS patients to receive aggressive therapy (either prostatectomy or radiation) in San Francisco-Oakland (odds ratio [OR] = 1.69, 95% CI = 1.46-1.96) but not in Seattle (OR = 1.15, 0.93-1.43). Among men receiving aggressive therapy, HMO cases were three to five times more likely to receive radiation therapy than prostatectomy. Overall mortality was equivalent over ten years (HMO versus FFS mortality risk ratio [RR] = 1.01, 0.94-1.08), but prostate cancer mortality was higher for HMO cases than for FFS cases (RR = 1.25, 1.13-1.39). CONCLUSION: Despite marked treatment differences for clinically localized prostate cancer, overall ten-year survival for patients enrolled in two nonprofit group/staff HMOs was equivalent to survival among patients receiving care in the FFS setting, even after adjustment for sociodemographic and clinical characteristics. Similar overall but better prostate cancer-specific survival among FFS patients is most plausibly explained by differences between the HMO and FFS patients in both tumor characteristics and unmeasured patient selection factors.     

How does managed care manage the frail elderly? The case of hospital readmissions in fee-for-service versus HMO systems

OBJECTIVES: This study examined whether hospital readmissions varied among the frail elderly in managed care versus fee-for-service (FFS) systems. SETTING AND PARTICIPANTS: Random sample of 450 patients, aged 65 and over, from a large vertically integrated health care system in San Diego, California. Participants were receiving physician-authorized home health and survived and 18-month follow-up period. MAIN OUTCOME MEASURES: Multiple logistic regression analyses were used to conduct comparisons of readmissions and preventable readmissions by plan type. Two methods to identify preventable readmissions were developed, one based on a computerized algorithm of service use patterns, and another based on blind clinical review. RESULTS: The odds of having a preventable hospital readmission within 90 days of an index admission were 3.51 (P = 0.06) to 5.82 (P = 0.02) times as high for Medicare HMO enrollees compared to Medicare FFS participants, depending on the method used to assess preventability. Readmission patterns were similar for Medicare HMO enrollees and FFS study participants dually enrolled in Medicare and Medicaid. CONCLUSION: In this group of frail elderly Medicare beneficiaries, those enrolled in an HMO were more likely to have a preventable hospital readmission than those receiving care under FFS. These results suggest that policies promoting stringent approaches to utilization control (e.g., early hospital discharge, reduced levels of post-acute care, and restricted use of home health services) may be problematic for the frail elderly.     

Effects of Medicaid managed care programs on health services access and use

OBJECTIVE: To estimate the effects of Medicaid managed care (MMC) programs on Medicaid enrollees' access to and use of health care services at the national level. DATA SOURCES/STUDY SETTING: 1991-1995 National Health Interview Surveys (NHIS) and a 1998 Urban Institute survey on state Medicaid managed care programs. STUDY DESIGN: Using multivariate regression models, we estimated the effect of living in a county with an MMC program on several access and use measures for nonelderly women who receive Medicaid through AFDC and child Medicaid recipients. We focus on mandatory programs and estimate separate effects for primary care case management (PCCM) programs, health maintenance organization (HMO) programs, and mixed PCCM/HMO programs, relative to fee-for-service (FFS) Medicaid. We control for individual and county characteristics, and state and year effects. DATA COLLECTION/EXTRACTION METHOD: This study uses pooled individual-level data from up to five years of the NHIS (1991-1995), linked to information on Medicaid managed care characteristics at the county level from the 1998 MMC survey. PRINCIPAL FINDINGS: We find virtually no effects of mandatory PCCM programs. For women, mandatory HMO programs reduce some types of non-emergency room (ER) use, and increase reported unmet need for medical care. The PCCM/HMO programs increase access, but had no effects on use. For children, mandatory HMO programs reduce ER visits, and increase the use of specialists. The PCCM/HMO programs reduce ER visits, while increasing other types of use and access. CONCLUSIONS: Mandatory PCCM/HMO programs improved access and utilization relative to traditional FFS Medicaid, primarily for children. Mandatory HMO programs caused some access problems for women.     

An Analysis of Unobserved Selection in an Inpatient Diagnostic Cost Group Model

The study assesses unobserved selection bias in an inpatient diagnostic cost group (DCG) model similar to Medicare's Principal Inpatient Diagnostic Cost Group (PIP-DCG) risk adjustment model using a unique data set that contains hospital discharge records for both FFS and HMO Medicare beneficiaries in California from 1994 to 1996. We use a simultaneous equations model that jointly estimates HMO enrollment and subsequent hospital use to test the existence of unobserved selection and estimate the true HMO effect. It is found that the inpatient DCG model does not adequately adjust for biased selection into Medicare HMOs. New HMO enrollees are healthier than FFS beneficiaries even after adjustment for the included PIP-DCG risk factors. A model developed over an FFS sample ignoring unobserved selection overestimates hospital use of new HMO enrollees by 28 percent compared to their use if they had remained in FFS. Models that better captures selection bias are needed to reduce overestimation of Medicare HMO enrollees' resource use.     

Evaluating Medicaid HMOs when encounter data are missing: case of developmentally delayed children

In evaluating Medicaid Health Maintenance Organizations (HMOs), crucial information regarding severity of illness of patients is often missing – in part because encounter data are not available. If we assume that patients are either in the HMO or in fee-for-service (FFS) plans (i.e., no in or out migration); then severity of HMO patients can be deduced from encounters of FFS patients. We applied this approach to effectiveness of HMO services for developmentally delayed children. Data supported the assumption of a closed system. Data also showed that over 12 months, severity of FFS patients declined. Therefore, we inferred that the HMO was attracting sicker patients. The HMO was paid less than FFS plan, despite the fact that it attracted sicker patients.     

The effect of HMOs on the inpatient utilization of medicare beneficiaries

OBJECTIVE: To determine the effect of joining HMOs (health maintenance organizations) on the inpatient utilization of Medicare beneficiaries. DATA SOURCES: We linked enrollment data on Medicare beneficiaries to patient discharge data from the California Office of Statewide Health Planning and Development (OSHPD) for 1991-1995. DESIGN AND SAMPLE: A quasi-experimental design comparing inpatient utilization before and after switching from fee-for-service (FFS) to Medicare HMOs; with comparison groups of continuous FFS and HMO beneficiaries to adjust for aging and secular trends. The sample consisted of 124,111 Medicare beneficiaries who switched from FFS to HMOs in 1992 and 1993, and random samples of 108,966 continuous FFS beneficiaries and 18,276 continuous HMO enrollees yielding 1,227,105 person-year observations over five years. MAIN OUTCOMES MEASURE: Total inpatient days per thousand per year. PRINCIPAL FINDINGS: When beneficiaries joined a group/staff HMO, their total days per year were 18 percent lower (95 percent confidence interval, 15-22 percent) than if the beneficiaries had remained in FFS. Total days per year were reduced less for beneficiaries joining an IPA (independent practice association) HMO (11 percent; 95 percent confidence interval, 4-19 percent). Medicare group/staff and IPA-model HMO enrollees had roughly 60 percent of the inpatient days per thousand beneficiaries in 1995 as did FFS beneficiaries (976 and 928 versus 1,679 days per thousand, respectively). In the group/staff model HMOs, our analysis suggests that managed care practices accounted for 214 days of this difference, and the remaining 489 days (70 percent) were due to favorable selection. In IPA HMOs, managed care practices appear to account for only 115 days, with 636 days (85 percent) due to selection. CONCLUSIONS: Through the mid-nineties, Medicare HMOs in California were able to reduce inpatient utilization beyond that attributable to the high level of favorable selection, but the reduction varied by type of HMO.     

How do HMOs achieve savings? The effectiveness of one organization's strategies.

OBJECTIVE: To examine how a group practice used organizational strategies rather than provider-level incentives to achieve savings for health maintenance organization (HMO) compared to fee-for-service (FFS) patients. DATA SOURCES/STUDY SETTING: A large group practice with a group model HMO also treating FFS patients. Data sources were all patient encounter records, demographic files, and clinic records covering 3.5 years (1986-1989). The clinic's procedures to record services and charges were identical for FFS and HMO patients. All FFS and HMO patients under age 65 who received any outpatient services during approximately 100,000 episodes of the seven study illnesses were eligible. STUDY DESIGN: Using an explanatory case design, we first compared HMO and FFS rates of resource utilization, in standardized dollars, which measured the impact of organizational strategies to influence patient and provider behavior. We then examined the effect of HMO insurance and organizational measures to explain total outpatient use. Key variables were standardized charges for all outpatient services and the HMO's strategies. PRINCIPAL FINDINGS: Patient and provider behavior responded to organizational strategies designed to achieve savings for HMO patients; for instance, HMO patients used midlevel providers and generalists more often and ER and specialists less often. Overall HMO savings, adjusted for case mix, were explained by the specialty of the physicians the patients first visited and appeared to affect patients with average health more than others. CONCLUSION: Organizational strategies, without resort to differential financial incentives to each provider, resulted in lower rates of outpatient services for HMO patients. Savings from outpatient use, especially for common diseases that rarely require hospitalization, can be substantial.     

Consumer acceptance of prepaid and fee-for-service medical care: results from a randomized controlled trial.

Do consumers find the care provided by health maintenance organizations (HMOs) and that provided in the fee-for-service (FFS) system equally acceptable? To address this question, we randomly assigned 1,537 people ages 17 to 61 either to FFS insurance plans that allowed choice of physicians or to a well-established HMO. We also studied 486 people who had already selected the HMO (control group). Those who had chosen the HMO were as satisfied overall with medical care providers and services as their FFS counterparts. The typical person assigned to the HMO, however, was significantly less satisfied overall relative to FFS participants. Attitudes toward specific features of care favored both FFS and HMO, depending on the feature rated. Four differences (length of appointment waits, parking arrangements, availability of hospitals, and continuity of care) favored FFS; two (length of office waits, costs of care) favored the HMO. HMO versus FFS differences in ratings of access to care and availability of resources mirror differences in the organizational features of these two systems that are generally considered responsible for the significantly lower medical expenditures at HMOs. Regardless of their origin, less favorable attitudes toward interpersonal and technical quality of care in the HMO have marked consequences: dissatisfaction and disenrollment.     

Effects of managed care on southern youths' behavioral services use

Children and adolescents' access to Medicaid-financed behavioral health services was examined over 8 years in Tennessee (managed care) and Mississippi (fee-for-service [FFS]) using logistic regression. Managed care reduced access to behavioral care overall, overnight services (e.g., inpatient), and specialty outpatient services. Managed care also restricted the relative use of overnight and specialty outpatient for children and adolescents. However, managed care had pronounced effects on use of case management services. We also document differences in access and mix of behavioral services used over time by race, sex, age, and Medicaid enrollment category.     

Use of ambulatory health services by the near poor.

Individuals in the gray area between Medicaid eligibility and sufficient income to meet the costs of health care, the near poor, utilize health services less than other groups. As part of a study of health care behavior in an inner-city area based on a household survey of three distinct populations (HMO) members, public housing project residents, and a defined geographical area), we examined this question more thoroughly. Survey results show that the near poor had lower levels of use than Medicaid recipients when other factors were controlled. Particularly among those classified as in poor health, the near poor were more likely to be non-users and less likely to make multiple visits. However, differences in use between the near poor and the Medicaid recipients are substantially and consistently smaller for the HMO users (whose costs were covered by a special contract) than for users of a hospital outpatient department. The patterns persist for regular care received for a chronic condition but not for care sought for episodes of illness. These findings point to the special disadvantage faced by low income individuals who are not receiving Medicaid.     

HMO vs fee-for-service care of older persons with acute myocardial infarction.

OBJECTIVES. Health maintenance organizations (HMOs) continue to grow in number and in their enrollment of Medicare recipients. They are also increasingly viewed as organizational structures that might contribute to control of health care costs. Yet little is known about the quality of care that elderly HMO enrollees receive. METHODS. We compared patients from three HMOs to a fee-for-service (FFS) sample that was national in scope. Sickness at admission, the quality of process of care, and mortality were assessed for patients aged 65 years and older who had been hospitalized with a diagnosis of acute myocardial infarction. RESULTS. After adjustment for sickness at admission, there were no significant mortality differences between the HMO and FFS groups at either 30 (23.2% vs 23.5%) or 180 days (34.4% vs 34.5%) after admission. Compliance with process criteria was higher for the HMO group as a whole (P < .05). The HMOs had greater compliance with three of five scales measuring different aspects of care for patients with acute myocardial infarction. CONCLUSIONS. We conclude that older patients from our participating HMOs who were hospitalized for acute myocardial infarction received hospital care that was generally better in terms of process than that received by patients in a national FFS sample.     

Enrollee health status under Medicare risk contracts: an analysis of mortality rates.

Previous studies comparing the health status of Medicare beneficiaries enrolled under HMO risk contracts to that of Medicare beneficiaries in fee-for-service (FFS) have generally focused on demonstration projects conducted before 1985. This study examines mortality rates in 1987 for approximately 1 million aged Medicare beneficiaries enrolled in 108 HMOs. We estimated adjusted mortality ratios (AMR) for each HMO and across all HMOs, by dividing the actual number of deaths among HMO enrollees by the "expected" number of deaths. The expected number of deaths was based on death rates among local FFS populations, adjusting for age, sex, Medicaid buy-in status, and institutional status. The AMR for all HMO enrollees pooled together was 0.80. For persons newly enrolled in 1987, the AMR was 0.69; in general, AMRs were higher for beneficiaries who had been enrolled for longer periods of time. Among individual HMOs, none exhibited an AMR substantially above 1.00. Regression analysis indicated lower AMRs for staff model HMOs than for either IPA or group models. Low mortality among Medicare HMO enrollees is consistent with favorable selection or with improvements in the health status of enrollees due to better access or quality of care in HMOs. In either case, health status differences between HMO enrollees and FFS beneficiaries have implications for the appropriateness of Medicare's Adjusted Average Per Capita Cost (AAPCC) payment formula for HMOs.     

Medicaid Managed Care and Health Care for Children

Objective. Many states expanded their Medicaid managed care programs during the 1990s, causing concern about impacts on health care for affected populations. We investigate the relationship between Medicaid managed care enrollment and health care for children.
Data Sources and Measures. Repeated cross-sections of Medicaid-covered children under 18 years of age from the 1996/1997 and 1998/1999 Community Tracking Study Household Surveys ( n =2,602) matched to state-year CMS Medicaid managed care enrollment data. For each individual, we constructed measures of health care utilization (provider and emergency department visits, hospitalizations, surgeries); health care access (usual source of care, unmet medical needs, put-off needed care); and satisfaction (satisfaction overall, with doctor choice, and with last visit).
Study Design. Regression analysis of the relationship between within-state changes in Medicaid managed care enrollment rates and changes in mean utilization, access, and satisfaction measures for children covered by Medicaid, controlling for a range of potentially confounding factors.
Principal Findings. Increases in Medicaid health maintenance organization (HMO) enrollment are associated with less emergency room use, more outpatient visits, fewer hospitalizations, higher rates of reporting having put off care, and lower satisfaction with the most recent visit. Medicaid primary care case management (PCCM) plans are associated with increases in outpatient visits, but also with higher rates of reporting unmet medical needs, putting off care, and having no usual source of care.
Conclusions. Both Medicaid HMO and PCCM plans can have important impacts on health care utilization, access, and satisfaction. Some impacts may be positive (e.g., less ED use and more outpatient provider use), although concern about increasing challenges in access to care and satisfaction is also warranted.     

Medicaid managed care in New York City: recent performance and coming challenges

OBJECTIVES: This study evaluated New York City's voluntary Medicaid managed care program in terms of health care use and access. METHODS: A survey of adults in Medicaid managed care and fee-for-service programs during 1996-1997 was analyzed. RESULTS: Responses showed significant favorable risk selection into managed care but little difference in use of health care services. Although some measures of access favored managed care, many others showed no difference between the study groups. CONCLUSIONS: The early impact of mandatory enrollment will probably include an increase in the average risk of managed care enrollees with little change in beneficiary use and access to care.     

The impact of payor/provider type on health care use and expenditures among the frail elderly.

OBJECTIVES: This study examined whether health care expenditures and usage by the frail elderly differ under three payor/provider types: Medicare fee for service, Medicare health maintenance organization (HMO), and dual Medicare-Medicaid enrollment. METHODS: In-home interviews were conducted among 450 frail elderly patients of a San Diego, Calif, health care system. Cost and use data were collected from providers. RESULTS: Analyses revealed no difference in total expenditures between fee-for-service and HMO enrollees, but Medicare-Medicaid beneficiaries' expenditures were 46.8% higher than those for HMO enrollees and 52.2% higher than those for the fee-for-service group. Fee-for-service participants were less than half as likely as HMO enrollees to have two or more hospital admissions, but hospital usage rates between those two payor/provider groups did not differ. Not were there payor/provider differences in access to home health care, but HMO home health care users received significantly fewer services than the others. CONCLUSIONS: The care provided to these HMO beneficiaries resulted in a combination of restricted home health use and higher multiple hospitalizations. This raises compelling questions for future research. For the dually enrolled, stronger cost containment may be required.     

Partially capitated managed care versus FFS for special needs children

Little research has examined whether Medicaid managed care plans (MCPs) that incorporate case management are effective in coordinating services for children with special health care needs (CSHCN). This study evaluates the effects of enrollment of special needs children into a partially capitated MCP (with ongoing case management) versus the fee-for-service (FFS) option on use of therapeutic services, specifically speech, occupational, and physical therapy by site of service (school versus health care sector). Results show that special needs children enrolled in the partially capitated MCP are significantly more likely to obtain occupational and physical therapy at school relative to their FFS counterparts. Moreover, children enrolled in FFS are significantly less likely to be either regular or frequent users of each type of therapy relative to children enrolled in managed care. We attribute much of these disparities in use of therapeutic services at school to the availability of case management and coordination that is an integral component of the partially capitated MCP.     

Service-level selection by HMOs in Medicare

In the federal Medicare program, contracting health maintenance organizations (HMOs) are paid on a capitated basis. There has long been concern that an "adverse selection" of risks remain in the traditional fee-for-service (FFS) sector, since beneficiaries with low costs may leave the FFS sector and join the HMOs. The distortion associated with this form of selection is that health plans may design their mix of health care services in order to effectuate favorable selection. This paper scrutinizes patterns of HMO membership and costs by service in the FFS sector for evidence consistent with the hypothesis that HMOs engage in service-level product distortion. We develop a multi-service model of choice between FFS and HMOs and show that if the HMO sector is underproviding (overproviding) a service relative to the FFS sector, we should observe a positive (negative) correlation between the HMO market share and average costs of those remaining in the FFS sector. We estimate the correlation between the HMO market share and the average FFS costs for different health care services using Medicare data for 1996. We find evidence indicating that there exists significant service-level selection by HMOs.