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Age and Ageing Advance Access published online on May 30, 2008
Age and Ageing, doi:10.1093/ageing/afn120
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Copyright © The Author 2008. Published by Oxford University Press on behalf of the British Geriatrics Society.

Post-acute care for older people in community hospitals—a cost-effectiveness analysis within a multi-centre randomised controlled trial

Jacqueline O'reilly1, Karin Lowson2, John Green3, John B. Young3 and Anne Forster3

1 Health Research and Information Division, Economic and Social Research Institute, Dublin, Ireland
2 York Health Economics Consortium Ltd., University of York, York, UK
3 Academic Unit of Elderly Care and Rehabilitation, University of Leeds, Bradford, UK

Address correspondence to: J. B. Young. Academic Unit of Elderly Care and Rehabilitation, University of Leeds, Bradford Royal Infirmary, Duckworth Lane, Bradford BD9 6RJ, UK. Tel: +44 (0)1274 383406; Fax: +44 (0)1274 382766. Email: john.young{at}bradfordhospitals.nhs.uk


   Abstract
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 Abstract
Introduction
 Methods
 Results
 Discussion
 Key points
 Conflicts of interest...
 References
 
Objectives: to compare the cost effectiveness of post-acute care for older people provided in community hospitals with general hospital care.

Design: cost-effectiveness study embedded within a randomised controlled trial.

Setting: seven community hospitals and five general hospitals at five centres in the midlands and north of England.

Participants: 490 patients needing rehabilitation following hospital admission with an acute illness.

Intervention: multidisciplinary team care for older people in community hospitals.

Measurements: EuroQol EQ-5D scores transformed into quality-adjusted life years; health and social service costs during the 6-month period following randomisation.

Results: there was a non-significant difference between the community hospital and general hospital groups for changes in quality-adjusted life-year values from baseline to 6 months (mean difference 0.048; 95% confidence interval –0.028 to 0.123; P = 0.214). Resource use was similar for both groups. The mean (standard deviation) costs per patient for health and social services resources used were comparable for both groups: community hospital group £8,946 (£6,514); general hospital group £8,226 (£7,453). These findings were robust to sensitivity analyses. The incremental cost-effectiveness ratio estimate was £16,324 per quality-adjusted life year. A cost effectiveness acceptability curve suggests that if decision makers' willingness to pay per quality-adjusted life year was £10,000, then community hospital care was effective in 47% of cases, and this increased to only 50% if the threshold willingness to pay was raised to £30,000.

Conclusions: the cost effectiveness of post-acute rehabilitation for older people was similar in community hospitals and general hospitals.

Keywords: health services for the aged, sub-acute care, convalescent hospitals, costs and cost analysis, aged 80 and over, elderly


   Introduction
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Methods
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Community hospitals are an existing, well established form of health care, widely available across the United Kingdom with the potential to provide intermediate care services for older people[1]. However, the evidence base for their clinical and economic impact is not robust[2]. Purchasers should be reluctant to commit funds to services where effectiveness and cost effectiveness have not been demonstrated, particularly where investments such as community hospitals or other intermediate care facilities may be significant.

We report on an economic evaluation that was embedded within a randomised controlled trial of community hospital care for older people. Following an acute admission, medically stable patients were randomised to transfer to a community hospital or to remain in the general hospital for rehabilitation. The study took place within five centres in the midlands and north of England. A previous report has described the study patients, sites and trial methods[3]. The main clinical outcome result was a clinically modest but statistically significant difference in independence at 6 months for patients randomised to community hospital care[4]. The clinical outcomes and economics results for one centre have been reported separately[5, 6]. The economic data for the patients from this centre are also included in the present analysis of all five participating centres with the intention to describe a more representative estimate for the cost effectiveness of post-acute rehabilitation care in community hospitals.


   Methods
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 Abstract
 Introduction
 Methods
Results
 Discussion
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 References
 
Study population
Multi-centre and local Research Ethics Committees approved the study. Recruitment to the randomised controlled trial took place in general hospitals in five centres with seven associated community hospitals over a period of 34 months from November 2000. Patients were eligible for the trial if they had an address within the catchment area of the relevant community hospital and, in the opinion of their attending senior physician, were medically stable and in need of post-acute rehabilitation care prior to an anticipated home discharge. Patients with features of medical instability (pyrexia, breathlessness at rest, history of chest pain within the previous 48 h, or need for intravenous medication)[7]; patients who were drowsy or unconscious; patients requiring stroke unit rehabilitation, or treatment in other departments such as surgery or coronary care; and patients who needed new residential or nursing home placement, were excluded from the trial. Patients and their carers gave written informed consent, or assent was sought from a carer or relative where patients had impaired capacity. Of the 490 patients recruited to the study, 280 were randomised to a community hospital and 210 to general hospital care. The characteristics of the intervention and control groups were similar at baseline[4].

Economic evaluation
The economic evaluation adopted a whole-systems approach investigating the relative costs of the two treatment settings to the NHS and Social Services during the 6 months following randomisation.


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  		Table 1. Mean QALY values at each assessment point

 

Outcome measure
Health outcome for the economic study was measured by the EuroQol EQ-5D[8] administered by a researcher recorded at 1 week after hospital discharge, and at 3 and 6 months after recruitment. The EQ-5D contains five health items, which have been valued by the general public for use in cost-utility analyses[9]. This utility measure incorporates individual preferences or weights attached to health-related quality of life and, because it produces a single index, is suitable for economic evaluation. This measure is not disease-specific and therefore can be used to evaluate and compare the health impact of a range of different interventions and diseases[8]. It is acceptable to older people with good response rates (81%), and is sensitive to change[10].

The EuroQol scores were transformed into quality-adjusted life years (QALY)[11] on the assumption that no further change in the score occurred during the remainder of the year.


Resource utilisation
Resource utilisation data were obtained through a questionnaire administered by a researcher at the same time points as the EQ-5D. The questionnaire was designed to collect information on the utilisation of several resource categories including hospital admissions; visits to accident and emergency departments, day hospitals, day centres, general practitioners and hospital outpatient departments; and use of out-of-hours services, home visits by health or social care staff, residential and nursing care homes, and aids and adaptations. The primary source for information on inpatient hospital care and hospital outpatient visits was the Patient Administration System within each trust. Subsequent elective hospital admissions, for example for cataract extractions or joint replacement procedures, for patients on an elective surgical waiting list that pre-dated trial recruitment were excluded on the basis that they were not related to the index admission or to community hospital care.


Costs
Unit cost data were obtained from both national and local sources. Cost data for the post-randomisation length of hospital stay in the general hospitals of the participating trusts were sourced from the Chartered Institute of Public Finance and Accountancy database[12] which records hospital trusts' financial returns and from which the general hospital speciality costs could be obtained. The per diem costs for community hospital care were derived from a detailed analysis of the costs of one community hospital[6]. To be comparable with the general hospitals, the community hospitals' per diem rates comprise both direct and indirect costs, including expenditure on support services, estates and staffing costs (incorporating nursing establishment, consultant, general practitioner, physiotherapist and occupational therapist, therapy helper, speech and language therapist and dietician). The costs for the index community hospital were then applied to all seven community hospital sites in estimating the total costs of the initial admission and subsequent community hospital readmissions. Costs for readmissions to the general hospital were based on trust-specific health resource group costs[13], increased by a per diem cost if the actual length of stay was in excess of that expected from the trust-specific health resource group. Community service costs were obtained from Personal Social Services Research Unit tables[14]. Where patients made a financial contribution, it was assumed that they incurred the total cost in the case of community services and 30% of the costs for institutional care.

The price year was 2001–02 and the currency was UK pounds sterling. Since the timescale of the trial was less than 1 year, it was not necessary to discount costs and health benefits.


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  		Table 2. Mean health and social care resources used by patients in the community hospital and general hospital groups during the 6-month follow-up period

 

Analysis
A cost-effectiveness approach to the economic analysis over the 6 months of the study was adopted using the intention-to-treat principle. Patients who died were assigned a QALY value of zero for the follow-up period in which the death occurred. Changes in QALY scores from baseline to 6 months between the intervention and control groups were reasonably normally distributed and were compared using the unpaired t-test. Individual patient costs were calculated by multiplying resource volumes by unit costs. Cost data were skewed. Mean differences and their 95% confidence intervals in component categories of cost data and total cost data between the intervention and control groups were reported. Additionally, by simulating the process of repeated data gathering from the same population, non-parametric bootstrapping was used to estimate the distribution of incremental costs and benefits associated with the community hospital and general hospital groups. When information about the costs of alternative treatments is to be used to guide health care policy decision making, it is the total budget needed to treat patients that is relevant[15]. For this reason, we have presented the results in terms of mean costs per patient treated[15]. This more readily assists an interpretation by health care planners to determine budget allocations for the two health care settings.

The incremental cost-effectiveness ratio was calculated as the ratio of the differences between the two groups for mean costs and mean QALY values per patient. In calculating the incremental cost-effectiveness ratio, patients with missing QALY values were assumed to have scores equal to the mean patient in their treatment group. To gain an understanding of the uncertainty surrounding the incremental cost-effectiveness ratio, a cost-effectiveness acceptability curve was estimated using a non-parametric bootstrap method on the basis of 10,000 replications[16, 17]. The cost-effectiveness acceptability curve indicates the probability that community hospital care will be cost effective relative to the alternative general hospital care, given a particular level of the decision maker's willingness to pay for an additional QALY[18]. The initial hospital admission, subsequent readmissions and institutional care costs were substantial cost drivers, and were therefore explored in sensitivity analyses. We also explored the per diem rate at which a cost equilibrium occurred between the two care settings.

The study was funded by the Department of Health and the Medical Research Council and included a previous single-centre study, which was funded by The Health Foundation. The financial sponsors had no role in the design, execution, analysis and interpretation of data, or writing of the study.


   Results
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 Abstract
 Introduction
 Methods
 Results
Discussion
 Key points
 Conflicts of interest...
 References
 
Baseline QALY values were lower in the community hospital group but higher at each of the three follow-up assessment points compared with the general hospital group (Table 1). There was a non-significant difference between the groups for changes in QALY values from baseline to 6 months in favour of the community hospital group (mean difference 0.048; 95% confidence interval –0.028 to 0.123; P = 0.214). The number of patients reporting utilisation of health and social care resources, the quantity and costs of resources used were similar for both the community hospital and general hospital groups (Table 2). The mean (standard deviation) costs of health and social services resources used per patient were similar for both groups: community hospital group, £8,946 (£6,514); general hospital group, £8,226 (£7,453); mean difference £720 (95% confidence interval–£523 to £1,964) (Table 3). The bootstrapped mean incremental cost-effectiveness ratio was £16,324 per QALY. The cost-effectiveness acceptability curve (See Appendix 1 in the supplementary data on the Journal's website http://www.ageing.oxfordjournals.org.) suggested that if decision makers' willingness to pay per QALY was £10,000, then community hospital care was effective in 47% of cases and this increased to only 50% if the threshold willingness to pay was raised to £30,000.


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  		Table 3. Cost per patient (UK£) and results of the sensitivity analyses

 
The results of the sensitivity analyses (Table 3) indicated that the economic results were robust to underlying assumptions. Using national rather than site-specific general hospital costs, or restricting costs of readmissions to exclude the costs incurred by extended lengths of stay, did not alter the conclusions. Institutional care costs were also robust to changes in the assumption regarding patient contributions to the cost of institutional care. An exploratory analysis showed that the mean cost per patient in the community hospital group became less than the general hospital group only when the per diem rate for the community hospital was reduced by over 30% (from £148 to £100).


   Discussion
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 References
 
Internationally, many health services have been developing intermediate care policies. Primarily, this has been to reduce demands for acute hospital care but there has also been a perception that these services would offer greater cost effectiveness. There is, however, scant evidence for greater cost effectiveness associated with intermediate care. Nurse-led unit care[19] and residential care home-based rehabilitation[20] appear to substantially prolong overall lengths of stay. Evaluations of hospital-at-home services have reported inconsistent findings in respect of resources used and costs compared to traditional hospital care[21, 22].

Previous resource studies of community hospital care have investigated the impact on general hospital use by comparing patients in areas with and without access to community hospitals[23–25]. However, this is not an ideal method because essentially two different settings (rural and urban) are under comparison, and there are confounding factors with potential to influence bed use and length of stay. The renewed interest in community hospitals in the context of providing intermediate care[1] has highlighted the weakness in the evidence base and this is the first large-scale cost-effectiveness study of community hospital care. The results are applicable to one community hospital function: post-acute rehabilitation care for older people.

A key strength of the economic evaluation study is that it was embedded within a multi-centre randomised trial (which also incorporated patients from an earlier single-centre study). The economic perspective has been a whole-systems one of health and social care costs combined over the 6 months of the study, but has excluded the issue of apportioning costs for informal carer burden. However, the carer burdens in the clinical outcomes study were similar between the community hospital and control groups (unreported data). There are some limitations to our study. The mean age of the study population was 86 years, some of whom had cognitive impairment. There is, therefore, concern over the recall reliability for events and services received over the 6 months. This was mitigated by, whenever possible, interviewing patients in the presence of their carers. Furthermore, information on hospital stay, hospital outpatient visits and hospital readmissions (a major cost driver) was obtained from the hospital patient information system. Reported information concerning some community health and social services received was also checked for reliability against a computerised community database and moderate agreement was found. A further limitation was that the costs of the seven participating community hospitals were not separately calculated but we relied on a detailed costing study of one community hospital[6] and applied this result to the other six community hospitals. However, a sensitivity analysis indicated that it was only when the per diem cost at the community hospital was reduced by an implausible 30% that it became less expensive than the general hospital.

Concerns have been raised about the use of the EQ-5D measurement and the associated QALY calculation in respect of older people[26, 27]. It was used in our study because it remains the predominant method in health economic evaluation and is used by the National Institute for Health and Clinical Excellence (NICE) to assist in comparing and recommending interventions[28]. Furthermore, the EQ-5D has been found to be acceptable to very elderly patients (80+ years), with a good response rate (81%) and sensitivity to change[10, 29]. Alternative health economic methods could be either cost minimisation (assumes near-equal health outcome), or a cost-consequence analysis (a subtle variant of cost-effectiveness analysis). Cost-consequence analysis, however, does not readily relate benefits to costs because it creates a situation, in effect, of multiple outcomes, which may pull in different directions. It is not, therefore, a strongly recommended health economic evaluation method.

The clinical outcomes study[4] reported that patient independence was greater at 6 months in the community hospital group compared with the general hospital group. The main findings of our complementary economic study are that the health outcomes and costs between the two services were similar. The mean costs over 6 months of follow-up associated with community hospital care were £720 more per patient but this was not significantly different (95% confidence interval –£532 to £1,964) compared to general hospital care. Sensitivity analyses showed that the cost comparisons were robust to changes in the underlying assumptions. The estimate of cost effectiveness, the incremental cost-effectiveness ratio, was £16,324—well within the notional £30,000 threshold used by the NICE in their health technology appraisals[30]. Although the assumption that QALY scores were set equal to the mean for patients with missing QALY values will have reduced the variance of the QALYs, and thus the variance of the incremental cost-effectiveness ratio, the effect is likely to have been small as only 65 (13%) patients (community hospital group 35 (13%) general hospital group 30 (14%)) were involved.


   Key points
Top
 Abstract
 Introduction
 Methods
 Results
 Discussion
 Key points
Conflicts of interest...
 References
 

  • Community hospitals are a long established and important component of health care provision in England.
  • Previous health economic studies of community hospital care have been methodologically weak and difficult to interpret.
  • This study was a health economic evaluation of community hospitals compared to general hospital care and was embedded within a multi-centre randomised controlled trial design.
  • Quality-adjusted life-year values and resource use were similar in both groups. The mean (standard deviation) costs per patient were: community hospital group £8,946 (£6,514); general hospital group £8,226 (£7,453).
  • Community hospitals offer similar cost effectiveness to a general hospital for post-acute care of older people in need of rehabilitation.


   Acknowledgements
 
We thank our colleagues in the elderly care departments, the managers and staff at the participating community hospitals and general hospitals, the patients and carers who took part in the study, Emma Tanner for assisting in the management of the study, Karen Mallinder for assisting in researcher training and support, Margaret Dean, Linda Dobrzanska, Yvonne Parker, Ruth Rea, Anne Schofield, Philippa Scothern, Len Stevens, Annette Strickland, Teresa Taylor, Helen Ward and Helen Wright for recruiting and following-up the patients and carers.


   Conflicts of interest declaration
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 Methods
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 Discussion
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 Conflicts of interest...
References
 
There are no conflicts of interest to declare.


   References
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 Methods
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Received 3 October 2007; accepted in revised form 18 April 2008.


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