Results were expected in some areas and unexpected in others. Despite integration and uniformity in many aspects of the system, the interplay of patient and subregional characteristics that contributed to different PAC utilization as well as some variation during the time period of the study were observed.
Rather than demonstrating differences in care based solely on minority status, the findings indicate that disparities in rehabilitation services provided after stroke may be caused by complex interrelationships of socioeconomic factors, including income, age, sex/gender, race/ethnicity, geographic factors, and type or severity of stroke. Cultural factors, yet to be determined, also may play a role in the determination of the types of services and the settings of care for subpopulations from various ethnic groups.
Unexpectedly, it was found that white patients in our population were less likely to go to an IRH and, in fact, other racial/ethnic groups, namely Asian and black populations, were more likely to receive care in this setting. White women were more likely to be treated in an SNF even after adjusting for other explanatory variables, including age and type of stroke. Median household income was a significant factor in receipt of SNF care, ie, patients with lower income were more likely to go to SNF. Proximity to the regional IRH also was associated with the care health plan members received.
The longer average LOS in acute hospital for patients going to IRH may be a proxy for severity or may represent the longer period required to secure a bed in an IRH as compared with other settings that are more accessible because of geographic proximity, admission criteria, and process of referral and decision-making. Discharge to a SNF under Centers for Medicare and Medicaid reimbursement guidelines allows for a longer LOS (up to 100 days) in a SNF as compared with an IRH (not reimbursed under Medicare for more than 30 days for a patient with a stroke) [21
]. In addition, SNFs are more available in a wider geographic area and more readily accessible than the one IRH in the system at the time of this study.
The variation in discharge level of care by acute hospitals within the system may reflect differences in decision-making by discharge planners or physicians. Referral patterns may vary because of the availability of PM&R physicians for consultation and assistance in functional prognostication, medical appropriateness, and determination of the best setting for rehabilitation after acute hospitalization.
Educational factors such as patient and family knowledge about the differences in PAC and rehabilitation services and the availability of information through professional contacts may lead to more likely placement in an IRH than SNF. Acculturation and health practices among racial/ethnic groups must be considered important in the investigation of health care disparities in health care delivery and outcomes. Recent research by Gordon [22
] in this health system, in which the author investigated educational level and race/ethnicity and health practices, suggests that differences in health status cannot be fully explained by differences in age and educational attainment within racial-ethnic groups.
Social and cultural factors, such as the number of caregivers available to secure a discharge plan for IRH placement, may be important determinants of sites of care after stroke. For certain populations, the culturally associated shame of placement in a long-term care facility may be operative in the process of decisions by patients and families about placement. When language barriers exist, choices may be uninformed or incompletely understood. For older white women, the absence of a caregiver, attributable to the more common lack of a spouse, partner, or other family member to provide care, may result in placement in a SNF rather than an IRH. Further research is necessary to clarify the contribution of cultural, linguistic, and other factors to decisions about PAC and stroke rehabilitation made by patients, families, physicians and other care providers.
In addition, further research is necessary to investigate whether the severity of the stroke or the rate of recovery from stroke varies across these populations. Factors other than stroke severity may contribute to LOS and, in ongoing research of the authors, the National Institutes of Health Stroke Scale [23
] is being used as an impairment measure so that groups can be stratified for further investigation of disparities and outcomes.
Kaiser Permanente health system’s regional and national offices have dedicated substantial resources to the identification and elimination of health care disparities through national and regional initiatives and research [24
]. This study will provide the basis for subsequent research and programmatic initiatives to further understand and ameliorate health care disparities within the health system. Geographic factors obviously played a role in access to care in our study, ie, the greater access to SNF beds than IRH beds in rural areas and areas not as close to the IRH facility, even though it was centrally located. The number of IRH beds in contrast to available SNF beds did play a role, as predicted, in the numbers of patients served in these settings [25
The findings in this study may not be generalizable to other health systems or other geographic regions. Differences among fee-for-service and managed health care in both utilization and outcomes of stroke patients have been demonstrated in previous studies [26
]. Racial/ethnic disparities in the delivery of health care services have been demonstrated to vary geographically, and variation in care practices do not fully explain these disparities [27
]. Further identification and investigation of provider and patient characteristics (including patient severity of illness and co-morbidities) within a health system such as this one will be necessary to fully explain the reasons for these disparities. Ethnic designations within data sets may be fraught with errors as the result of misclassifications and missing data, resulting in limitations to research in disparities. This problem is one that is identified in other health care systems such as the Veterans Administration system [28
]. In addition, the racial/ethnic groupings are quite broad in this and other studies (particularly for Asian and Hispanic populations), and further studies of subpopulations would be useful to identify the role of cultural and linguistic factors that may influence patient choice and access to rehabilitation services among these diverse groups.
As Buntin points out, nonclinical factors clearly affect PAC utilization, and access to care may be caused by a lack of clinical consensus about care pathways and appropriate settings of care as well as financial factors [29
]. The system under study here is a health system with prepayment financing and capitated rate-setting for Medicare populations, a quite different system of care from most systems in the United States. In addition, the population includes non-Medicare members. Access to care may be influenced by geographic factors, availability of beds for institutional care in IRH and SNF, or other types of care. The direct influence of these factors could not be determined.
When compared with other studies that included Medicare beneficiaries, the rates of treatment in IRH in our health system are lower (11.8%, range, 10.6–13.0 over the time period), with the percentages in three other Medicare studies being 16.2% [30
], 26.7% [31
], and 21.1% [32
]. The authors of these studies also acknowledge the challenges related to investigating the delivery of PAC in multiple settings, and the effects of changes in payment systems that may be influencing decision-making in other health systems during the period of this study.
The reasons for, or the effects of, these differences in utilization is beyond the scope of this study. Clearly, more research is needed to determine the best care settings and care pathways for patients with stroke [33
]. Further research into the reasons for variation in care delivery and utilization among culturally and otherwise-diverse populations must address patient and family characteristics, as well as physician/other provider, facility, health system, and financial factors that contribute to decision-making and outcomes after stroke.