The Importance of Rural Hospitals: Transfers and 30-day Readmissions Among Rural Residents and Patients Presenting at Rural Hospitals

Abstract

The purpose was to examine factors associated with transfers and readmissions among Medicare patients initially presenting at rural facilities. Data from the 2013 Medicare Claims file were used to identify fee-for-service patients with a hospital admission (n = 298,783) or an emergency department visit immediately followed by a hospital admission (117,416), for a total of 416,199. Transfers were defined as hospitalization at a different facility within 1 day of a discharge from a prior inpatient or emergency department encounter. For analysis of 30-day readmission, beneficiaries who died before discharge were excluded, for a total of 416,198 observations. Overall, 4.8% of index encounters resulted in a transfer. The transfer rate was higher for patients living in rural areas (9.8%, P < 0.0001), with the highest among residents of small rural areas (10.1%). The transfer rate was higher among those initial encounters in an urban facility (5.3%) than those admitted to a rural facility (2.7%, P < 0.0001). In adjusted analysis, beneficiaries with index encounters in rural or critical access facilities had higher odds of being transferred than those seen at urban facilities. The 30-day readmission rate was lower among patients presenting initially at rural versus urban hospitals (12.1% versus 19.2%). Although transfer status slightly increased the odds of rehospitalization in adjusted analysis, initial presentation at a rural facility was associated with reduced odds. The relatively high rate of transfers from rural hospitals to urban institutions suggests that systems must ensure that their patients' follow-up care meets their needs.

Introduction

Up to one third of rural Americans receive care in hospitals outside of their community of residence, often in urban areas.^1,2 These visits may be the result of rural residents bypassing their local hospital to seek care elsewhere or of transfer from their local rural or critical access hospital (CAH) to a larger urban facility.^3

–7 CAHs have additional needs for transfers, as facilities with this designation are limited in size (maximum of 25 acute care beds) and restricted to a 96-hour length of stay.⁸ Patient transfers can occur from either the emergency department or inpatient services, and for a variety of reasons. Among the most commonly cited reasons for transfers are the lack of services, intensity of services, or providers to perform necessary services at the original facility.^9

–16

Transfers from rural areas entail some level of risk. Delays can occur while processing the transfer, as well as when traveling to the receiving facility and processing the subsequent admission.^17
–19 Nonetheless, the need for transfers is high, as many rural and critical access facilities lack trauma services.⁹ Increasingly, they also lack obstetric care and other specialty services.^14,20 Transfers also add complexity to post-acute care coordination for hospitalized patients. Specifically, timely and appropriate treatment and follow-up care in the community upon discharge may be hindered by a lack of communication across providers, non-integrated medical records systems, a lack of financial incentives, and an overall lack of coordination across systems.^21,22

One indicator of poor care coordination is the 30-day readmission rate²³; with proper postdischarge care, this rate should be lower than without such care.^24,25 There is evidence that patients who are transferred are less likely to receive timely outpatient follow-up care and to have higher 30-day readmissions than those not transferred.^26,27 However, this relationship has not been not explored fully across disease conditions, settings, or across geographical boundaries. Further, studies of readmissions or postdischarge care may explicitly exclude transfers from their analyses.²⁸ Others have shown that 30-day readmission rates are lower among some rural residents, including those with diabetes or dually eligible for Medicaid.^29,30 Others have shown that CAHs have higher readmission rates than both rural and urban facilities.³¹ Further, the literature describing transfers from rural or critical access facilities is sparse. Prior work has been been limited to either emergency department transfers, small sample sizes,³² single states,⁷ old data,^32
–34 or CAHs.³⁵

The purpose of this analysis is to focus on rural populations and encounters at rural and critical hospital facilities, among patients with all conditions, to more fully examine the impact of transfers on 30-day readmissions.

Methods

Data source and population

Data for the analysis were drawn from the 2013 Medicare Claims files obtained from the Research Data Assistance Center (ResDAC); the Master Beneficiary Summary file plus Chronic Conditions Segment, Medicare Provider and Analysis Review (MedPAR) claims file (containing inpatient claims), outpatient claims file, and carrier claims file (containing physician claims). Because the analysis relies on claims data, Medicare Advantage beneficiaries were not included in data obtained from ResDAC. Files were merged using a unique identifier to create a single analytic file with all encounters included.

The initial sample consisted of 2,906,607 beneficiaries. For all analyses, the unit of analysis was the beneficiary, established by the presence of an index encounter. Thus, the analytic sample was restricted to beneficiaries with an index hospitalization or emergency department visit, and their subsequent inpatient encounters. After deletions for missing data, the study sample for analysis of transfers was comprised of 298,783 beneficiaries with an index inpatient admission and 117,416 beneficiaries with an emergency department visit immediately followed by a hospitalization, for a total of 416,199 observations. For analysis of 30-day readmission, beneficiaries who died before discharge were excluded, for a total of 416,198 observations.

Variables

Transfers were defined as hospitalization at a different facility within 1 day of a discharge from a prior inpatient or emergency department encounter. These were identified in several ways: (1) inpatient discharges with a discharge disposition of “transfer,” (2) subsequent inpatient admissions with an admission source of “transfer from another facility,” or (3) emergency department visits with a discharge disposition of “transfer.” All analyses were delimited to beneficiaries with such an index encounter. Transfers to any facility other than a general acute care facility (such as skilled nursing or long-term care) were excluded.

Similarly, 30-day readmissions were defined as an acute care inpatient admission within 30 days of a prior discharge from an acute care hospitalization for any condition. Those who died upon discharge were excluded from the 30-day readmission population. Planned readmissions were excluded from the analysis, if indicated by the coding schema.

Information about the beneficiaries included age (in years), sex, and race/ethnicity (non-Hispanic white, non-Hispanic black, Hispanic, or other race). Information regarding each health care encounter included date, primary and secondary diagnoses, and type of encounter (inpatient, emergency department, other). For inpatient claims, discharge date diagnostic-related groups, discharge disposition, and facility identifier were included. Records with missing data for the variables of interest were excluded. In addition, the analysis included indicators of 12 chronic conditions, as identified by the Medicare Chronic Conditions segment of the beneficiary summary file (acute myocardial infarction [AMI], atrial fibrillation, congestive heart failure, cancer, chronic obstructive pulmonary disease [COPD], diabetes, hip fracture, ischemic heart disease, osteoporosis, arthritis, stroke/transient ischemic attack [TIA], and hypertension).

Rurality was based on zip code Census Tract approximations,³⁶ using the 2006 Rural-Urban Commuting Area Codes.³⁷ Codes 1.0, 1.1, 2.0, 2.1, and 3.0 were classified as urban. Rural was categorized as large rural (codes 4, 4.1, 4.2, 5, 5.1, 5.2, 6, 6.1), small rural (codes 7, 7.1, 7.2, 7.3, 7.4, 8, 8.1, 8.2, 8.3, 8.4), and remote rural (codes 9, 10, 11, 12, 9.1, 9.2, 10.1, 10.2, 10.3, 10.4, 10.5, 10.6). Patient residence was based on their reported zip code of residence, while facility location was based on the zip code of its physical location, identified via the National Plan and Provider Enumeration System.³⁸ CAHs were identified by their provider number within the MedPAR file; these are rural hospitals that meet specific requirements, such as distance to another hospital, and have limits on patient length of stay. Thus, hospitals were classified as urban or rural, and within rural, as CAHs versus all other (non-CAH).

Initial analyses examined the proportion of the population with an index encounter (inpatient or emergency department), subset by rurality of the beneficiary's residence, and the initial facility location and type. Transfer and 30-day readmission rates were then estimated by facility location and beneficiary residence, as well as the characteristics already described. All comparisons were tested using Wald chi-square tests of difference or analysis of variance, with an α = 0.05. Multivariable regression models were utilized to determine the factors associated with a transfer and a same-condition readmission within 30 days. For the purpose of these analyses, beneficiary residence and facility location were combined: urban residence/urban facility, urban residence/rural facility, and so on. This research was deemed exempt by the University of South Carolina Institutional Review Board.

Results

Initial admissions

Just over one fourth of the study sample lived in a rural area (27.9%), but only 18.1% of all the index encounters were in rural facilities (Table 1). However, the majority of rural residents (56.7%) sought care in a rural hospital (P < 0.0001). Nearly one fourth (23.4%) of remote rural residents sought care in a critical access hospital.

Table 1.

Distribution of Beneficiary Residence, by Initial Encounter Facility Type and Location, 2013 (n = 416,198)

	Hospital location
	Urban	All rural types	Rural (not CAH)	CAH
All Beneficiaries	81.9%	18.1%	13.6%	4.5%
Urban Residence^a	96.8%	3.2%	2.6%	0.6%
Rural Residence^a,b	43.3%	56.7%	42.1%	14.6%
Large Rural Residence^a,b	40.9%	59.1%	53.8%	5.3%
Small Rural Residence^a,b	46.1%	53.9%	31.5%	22.5%
Remote Rural Residence^a,b	44.7%	55.3%	31.9%	23.4%

Significantly different from urban facility location, α = 0.05.

Significantly different from rural residence, α = 0.05.

CAH, critical access hospital.

Overall, 4.8% of index encounters resulted in a transfer (Table 2). The transfer rate was higher for patients living in rural areas (9.8%, P < 0.0001), with the highest among residents of small rural areas. The transfer rate also was higher among those initial encounters in an urban facility. This proportion was lower among those admitted to a rural facility (P < 0.0001), and even lower among those admitted to a CAH (P < 0.0001). Other factors associated with a higher transfer rate included male sex, age younger than 85 years, white and other race, living in the Midwest or the South, and living in a county with 1 or 2 hospitals. In general, having a chronic condition was associated with a higher transfer rate, with patients with a history of AMI having the highest rate (Table 2).

Table 2.

Proportion with a Transfer or 30-Day Readmission, by Patient Characteristics, 2013 (n = 416,198)

	Percent with a transfer	Percent with a 30-day readmission
All	4.8	17.8
Beneficiary Residence
Urban (Ref)	3.2	19.6
All Rural	9.8^a	15.4^a
Large Rural	7.9^a	14.8^a
Small Rural	10.1^a	11.7^a
Remote Rural	9.7^a	12.4^a
Facility Location
Urban (Ref)	5.3	18.9
Any Rural	2.7^a	15.0^a
Rural Only	3.2^a	16.2^a
CAH Only	0.8^a	3.5^a
Sex
Male (Ref)	5.3	18.7
Female	4.4^a	17.3^a
Age Group, years
65–74 (Ref)	5.2	17.2
75–84	5.0	18.8^a
≥85	3.7^a	17.9^a
Race/Ethnicity
White (Ref)	5.1	17.8
African American	3.5^a	17.5
Hispanic	3.5^a	19.1^a
Other	4.8	19.5^a
Region
Northeast (Ref)	4.2	19.8
Midwest	5.4^a	16.5^a
South	4.8^a	17.5^a
West	4.2	18.5^a
Number of Hospitals in the County
0 (Ref)	6.0	16.7
1	8.3^a	14.0^a
2	6.6^a	15.7^a
>2	3.3^a	19.5^a
Specific Chronic Condition
Acute Myocardial Infarction	10.3^b	16.8^c
Atrial Fibrillation	5.3^b	17.9
Congestive Heart Failure	5.3^b	16.8^c
Cancer	5.0^b	17.7
Chronic Obstructive Pulmonary Disease	5.0^b	16.4^c
Diabetes	5.2^b	16.3^c
Hip Fracture	5.5^b	16.0^c
Ischemic Heart Disease	5.4^b	16.2^c
Osteoporosis	4.3	16.0^c
Arthritis	4.7	15.3^c
Stroke / Transient Ischemic Attack	5.5^b	16.2^c
Hypertension	5.2^b	15.9^c

Significantly different from the referent category, α = 0.05.

Proportion with this condition is significantly higher than those without the condition.

Proportion with this condition is significantly lower than those without the condition.

CAH, critical access hospital.

Table 2 also displays the proportion of admissions with a 30-day readmission; overall, 17.8% of discharges had a subsequent readmission. This rate was highest for urban residents, and decreased as rurality increased. This rate also was lower for initial encounters at rural facilities, particularly CAH facilities. Other factors associated with a higher 30-day readmission rate included male sex, age older than 74 years, Hispanic and other race, living in the Northeast and West, and living in a county with more than 2 hospitals. In general, having a chronic condition was associated with a lower readmission rate.

Table 3 displays the rates of 30-day readmissions, by presenting facility location and transfer status. Overall, discharges studied had a 30-day readmission rate of 17.8%. This rate was lower among beneficiaries first presenting at rural and CAH facilities compared to urban (P < 0.0001). Overall, transfer and non-transfer patients had similar 30-day readmission rates (ns); however, this relationship differed by location of the presenting facility. Among patients first presenting at an urban facility, readmission rates were higher for non-transfer than transfer patients (P > 0.001). Patients transferred after presenting at rural facilities, however, had higher rates of readmission than those presenting with the highest among rural non-CAH facilities, across all levels of rurality (Table 3).

Table 3.

30-Day Readmission Rates and Location, by Transfer Status and Index Encounter Location (n = 416,198)

	All	Urban	All rural	Rural (not CAH)	CAH only
All
30-Day Readmission Rate	17.8	19.2	12.1^a	15.3^a	3.1^a,b
Transfers
30-Day Readmission Rate	17.3	18.0^c	15.7^a,c	18.8^a,c	7.9^a,b,c
Non-Transfers
30-Day Readmission Rate	17.9	19.3	11.8^a	15.0^a	2.7^a,b

Significantly different from urban hospitals, α = 0.05.

Significantly different from rural (not CAH) hospitals, α = 0.05.

Significantly different from non-transfers in the same category.

CAH, critical access hospital.

Table 4 displays the results of the multivariable regression models estimating the likelihood of transfer and readmission, respectively. A significant interaction was found between beneficiary's location of residence and the facility location of the index encounter; therefore, a combined variable was created to reflect this. This interaction term was set as the combination of beneficiary residence (urban, large rural, and small + remote rural combined) with facility location (urban, rural only, CAH). Because of small sample sizes, the urban interaction term was collapsed into 2 categories: urban residence/urban facility, and urban residence/rural and CAH facility. Other categories are as listed in Table 4.

Table 4.

Adjusted Odds of a Transfer or a 30-Day Readmission, 2013 (n = 416,198)

	Transfer	30-Day readmission
	aOR (95% CI)	aOR (95% CI)
Beneficiary Residence / Facility Location Interaction
Urban / Urban	Ref	Ref.
Urban / Rural, CAH	2.89 (2.68, 3.11)	0.38 (0.35, 0.41)
Lg. Rural / Urban	2.04 (1.91, 2.17)	0.68 (0.65, 0.71)
Sm. & Remote Rural / Urban	2.19 (2.07, 2.33)	0.75 (0.72, 0.78)
Lg. Rural / Rural	2.32 (2.20, 2.44)	0.85 (0.82, 0.88)
Sm. & Remote Rural / Rural	3.04 (2.87, 3.22)	0.77 (0.74, 0.81)
Lg. Rural / CAH	3.86 (3.46, 4.31)	0.13 (0.11, 0.16)
Sm. & Remote Rural / CAH	4.03 (3.80, 4.28)	0.14 (0.12, 0.15)
Prior Discharge included a Transfer
No		Ref.
Yes		1.05 (1.01, 1.09)
Sex
Male	Ref.	Ref.
Female	0.88 (0.86, 0.91)	0.92 (0.91, 0.94)
Age Group, years
65–74	Ref.	Ref.
75–84	0.89 (0.86, 0.92)	1.14 (1.12, 1.16)
≥85	0.63 (0.61, 0.66)	1.09 (1.06, 1.11)
Race/Ethnicity
White	Ref.	Ref.
African American	0.82 (0.79, 0.86)	0.92 (0.90, 0.94)
Hispanic	0.99 (0.88, 1.10)	0.96 (0.91, 1.01)
Other	1.00 (0.92, 1.09)	1.05 (1.01, 1.10)
Region
Northeast	Ref.	Ref.
Midwest	0.95 (0.90, 0.99)	0.93 (0.91, 0.96)
South	0.86 (0.82, 0.90)	0.98 (0.96, 1.01)
West	0.91 (0.86, 0.96)	0.94 (0.91, 0.96)
Number of Hospitals in the County
0	Ref.	Ref.
1	1.27 (1.17, 1.37)	0.87 (0.83, 0.92)
2	1.20 (1.11, 1.30)	0.89 (0.85, 0.94)
>2	0.95 (0.88, 1.03)	0.94 (0.90, 0.99)
Specific Chronic Condition
Acute Myocardial Infarction	2.17 (2.07, 2.27)	1.05 (1.02, 1.09)
Atrial Fibrillation	1.09 (1.05, 1.13)	1.14 (1.11, 1.16)
Congestive Heart Failure	1.02 (0.98, 1.06)	1.13 (1.10, 1.15)
Cancer	1.00 (0.96, 1.04)	1.09 (1.06, 1.11)
Chronic Obstructive Pulmonary Disease	0.82 (0.79, 0.85)	1.02 (1.00, 1.04)
Diabetes	0.96 (0.92, 0.99)	1.03 (1.01, 1.05)
Hip Fracture	1.25 (1.17, 1.34)	0.98 (0.94, 1.03)
Ischemic Heart Disease	1.11 (1.06, 1.15)	0.92 (0.90, 0.94)
Osteoporosis	0.92 (0.87, 0.96)	0.98 (0.95, 1.01)
Arthritis	0.84 (0.81, 0.87)	0.85 (0.83, 0.86)
Stroke / Transient Ischemic Attack	1.17 (1.13, 1.22)	0.97 (0.95, 1.00)
Hypertension	1.22 (1.16, 1.28)	0.64 (0.63, 0.66)

Bold indicates that it is significantly different from the referent group, α = 0.05.

aOR, adjusted odds ratio; CAH, critical access hospital; CI, confidence interval; Lg, large; Sm, small.

Beneficiaries with index encounters in rural or CAH facilities had higher odds of being transferred than those seen at urban facilities. These odds increased as the rurality of residence increased, and were highest among residents of small or remote rural area presenting to a CAH (adjusted odds ration 4.03; 95% confidence interval [CI] 3.80–4.28). In addition, residents of large rural areas first presenting at urban facilities had increased odds of transfer, compared to urban residents/urban facilities.

Factors associated with a reduced odds of transfer included female sex, older age, African American race, not living in the Northeast, and having 1 or 2 hospitals in the county. The model also included a selection of 12 specific conditions as verified and included in the Medicare Chronic Conditions segment of the beneficiary summary file. Of these conditions, COPD, diabetes, osteoporosis, and arthritis were all associated with lower odds of transfer, while AMI, atrial fibrillation, hip fracture, ischemic heart disease, stroke/TIA, and hypertension were all associated with higher odds of transfer.

In adjusted analysis, transfer status was associated with increased odds of readmission within 30 days (Table 4). However, although transfers were more likely among patients presenting at rural facilities, opposite results were found for 30-day readmissions, holding transfer status equal. For example, an urban resident first presenting to a rural or CAH facility had adjusted odds of a 30-day readmission of 0.38 (95% CI 0.35–0.41) compared to urban residents at urban facilities. Within rural residents, those first seen at rural non-CAH facilities had a higher odds of a 30-day readmission than rural residents seen at CAH facilities, yet both remained lower than those at urban facilities. The adjusted odds of a CAH index encounter resulting in a 30-day readmission were very low for residents of large rural areas and small and remote rural areas (Table 4). Factors associated with higher odds of a 30-day readmission included male sex, older age, white and other race, living in the Northeast, not having a hospital in the county of residence, and several of the selected chronic conditions (Table 4).

Discussion

This analysis examined the transfer patterns among Medicare beneficiaries, focusing on those admitted to rural or CAH facilities. The finding that the likelihood of transfer increased as rurality of the patient's residence increased, and was further increased by being admitted to a rural or CAH facility, has important care and policy implications for these populations.

Although it is difficult to ascertain severity of illness using claims data, findings do support the critical role that rural facilities play in the care of patients, particularly CAHs. Of all index encounters among residents of small and remote rural areas, nearly 60% were in CAH facilities. The importance of local services for triage and stabilization, as well as definitive care, is not contradicted by the higher transfer rate among these CAH encounters. Studies have shown that for some conditions, triage and transport do not result in poorer care, and can actually result in better outcomes.^{17
–19,34,39,40} Without local facilities, these patients would be forced to travel directly to other locations, delaying the initiation of care and potentially leading to poorer outcomes.^18,41,42

In addition, a high proportion of 30-day readmissions among transferred patients were returns to the index hospital, indicating a need for local facilities to care for these patients. If trauma centers and hospitals continue to close in rural areas,^9,43
–45 patients in those areas may experience poorer health outcomes. Programs that focus on improved care coordination have demonstrated a reduction in the 30-day readmission rate across settings and conditions.^27
–29 This care coordination would be aided by the presence and continued support of community health centers, rural health clinics, and other providers in rural areas. This also may be an avenue requiring further research and demonstration projects to achieve desirable results.

The lower readmission rate among transfers from CAH facilities also is worth noting. This may be related to the lower overall transfer rate, reduced disease acuity of the patients, or some other unknown factor. There also is evidence that those transferred were more likely to be admitted to a long-term care or skilled nursing facility upon discharge from the second institution, which would reduce their likelihood of a readmission (data not shown). The magnitude of this difference, however, was small, ranging from 2.0–3.3 percentage points, and may not be large enough to contribute significantly. More research is needed to explore this issue.

Transfers from one community to another increase the challenges of adequate care coordination post discharge, leading to gaps in the care continuum. The higher 30-day readmission rate among rural transfer versus non-transfer patients is further evidence of a failure of care coordination post discharge, particularly among those admitted to rural facilities, because prior studies have found a positive link between adequate care coordination and lower rates,^{24,25,46
–48} particularly for earlier readmissions.⁴⁹ Medicare Accountable Care Organizations (ACOs) were created in part to better handle these transitions, and have demonstrated lower costs of care for transfers within their systems.⁵⁰ Further research into ACOs, particularly rural ACOs, would be vital to better understand their potential impact on care and system efficiency.

Transfers also had a higher in-hospital death rate (5.6%) compared to non-transfers (2.0%, data not shown). Among transfers, rural encounters were higher still, topping out at 6.3% among rural non-CAH facilities. Again, severity is difficult to ascertain; thus, it is unclear what proportion of deaths among transfers would be avoidable or caused by delays in care. Further work to explore this question would be helpful to improve the care delivery in these populations.

Limitations

The current work is subject to the limitations of a retrospective study conducted with administrative claims data. Thus, the clinical profile of patients is restricted to standardized disease categories. Because the analysis is restricted to Medicare fee-for-service patients, it may not be applicable to beneficiaries enrolled in managed care plans. Finally, the role of patient and physician preferences in the selection of the presenting and transfer institutions is not included.

Conclusions

Examinations of hospitals transfers are difficult because of uncertainty around the clinical need for such transfers. In addition, patient preferences have been shown to be drivers of transfers, even beyond clinical indications.⁵¹ These transfers also do not take into account those who seek care in facilities outside of their service area.^3,5,52,53 Regardless, as rural patients seek care outside of their communities, either by need, choice, or some other factor, systems must ensure that their follow-up care meets their needs.

Footnotes

Author Disclosure Statement

The authors declare that there are no conflicts of interest. This study was supported by the Federal Office of Rural Health Policy (FORHP), Health Resources and Services Administration (HRSA), US Department of Health and Human Services (HHS) under cooperative agreement U1CRH03711. The information, conclusions and opinions expressed in this study are those of the authors and no endorsement by FORHP, HRSA, HHS, is intended or should be inferred.

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