Economic Evaluation of Multidisciplinary Rehabilitation Following Hip Fracture

Author: Rachel Kathleen Milte

Milte, Rachel Kathleen, 2014 Economic Evaluation of Multidisciplinary Rehabilitation Following Hip Fracture, Flinders University, School of Health Sciences

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Abstract

Hip fracture is a major contributor to morbidity and mortality in Australia and worldwide. In addition, healthcare spending for individuals spikes following a hip fracture due to increased needs for medical and supportive care. Many patients with hip fractures are malnourished upon admission to hospital, which impacts upon the recovery and rehabilitation potential of patients, and is also a significant independent predictor of increases in healthcare costs. There is increasing scrutiny on healthcare spending and a need for approaches which demonstrate a return on investment. Therefore, finding effective strategies to improve recovery following a hip fracture is important. However rehabilitation following hip fracture is an expensive complex intervention involving multiple components (e.g. medical, nursing, and allied health interventions). Health economics has received increasing focus over the past decades as a way of evaluating not only the benefits from healthcare interventions but also their 'value for money'. The focus of this thesis was to apply a range of methods of economic evaluation to rehabilitation following hip fracture, especially focusing on nutrition and exercise therapy. The intent was to demonstrate the strengths and potential weaknesses of various approaches. Initially, a systematic review of the literature for economic evaluations of nutrition interventions for treatment or prevention of malnutrition was conducted (Chapter 2). Malnutrition is known to be common among patients with hip fractures, and therefore effective treatment strategies are useful in multidisciplinary rehabilitation strategies. Only 20 articles meeting the selection criteria were identified (with an intervention increasing protein and energy intake via the oral route). Studied interventions included the provision of fortified diets but most used commercial Oral Nutritional Supplements (ONS). Seven studies included a multidisciplinary intervention with malnutrition screening and assessment, physical activity interventions, or consultations from other health professionals. The systematic review identified that there were only few high quality cost-utility studies (the preferred method of economic evaluation for regulatory bodies in Australia and around the world), but three indicated likely cost-effectiveness of their interventions in populations of hospitalised and community dwelling adults. While there is promising initial evidence for the cost-effectiveness of nutritional strategies in treating and preventing malnutrition, further studies utilizing preferred methods of economic evaluation are needed to provide more rigorous evidence to inform decision makers, especially in populations of frail older adults. To add to the evidence for providing nutrition therapy in frail, older adults at risk of malnutrition, an economic evaluation was undertaken of a multidisciplinary rehabilitation strategy including an individualised program of nutrition and exercise therapy provided for six months following a hip fracture (Chapter 3). The study followed a cost-utility methodology, and therefore quality adjusted life years (QALY) were used to assess the benefits of the intervention. The incremental cost effectiveness ratio (ICER) calculated was $AUD28,350 which although large was below the implied cost effectiveness ratio of $50,000 for Australia. Therefore, it is likely that this intervention of multidisciplinary rehabilitation would be considered cost-effective in Australia. In addition to applying economic evaluation methods to healthcare interventions, this thesis also looked further into methodological issues surrounding cost-utility studies as they are applied to multidisciplinary rehabilitation strategies in frail older adults, namely the measurement of quality of life for calculation of QALY gain. A subsequent study applied two different instruments for measuring quality of life and QALY to a population of older adults following hip fracture to compare their performance (Chapter 4). It was found that the ICECAP-O, a relatively new instrument designed specifically for use in older adults, was highly correlated (r=0.529, p=0.000) with the EQ-5D-3L, a traditional instrument used worldwide for the measurement of quality of life. However, there were some systematic differences between the two instruments with the mean utility score generated from the ICECAP-O almost 0.01 higher than the score generated from the EQ-5D-3L, and this reached statistical significance (z=-3.613 p=0.000). Further work is needed to compare the performance of the new ICECAP-O instrument against more traditional instruments, especially overtime and in the generation of benefits for use in cost-utility studies. In a final study (Chapter 5), patients' preferences for different configurations of rehabilitation programs were elicited utilising an economic technique known as a discrete choice experiment (DCE). In this study, patients were averse to rehabilitation programs involving very high levels of therapy and severe levels of pain, but not to lower levels of therapy and moderate levels of pain. The mobility outcome achieved from rehabilitation therapy following a hip fracture was found to be the most important determinant of rehabilitation program preference, in our sample of frail older adults. Importantly included in this study were two groups usually excluded from studies of this nature, those with cognitive impairment and from a nursing home. The study also highlighted the ability of discrete choice experiment techniques to be used to elicit preferences of frail older adults for multidisciplinary rehabilitation interventions. In summary this thesis has identified that a number of economic methods can be successfully applied to the evaluation of rehabilitation approaches in older adults, and it is recommended that methods of economic analysis should be more widely applied to evaluate nutritional and rehabilitation strategies in the future to improve the evidence-base for practice in this area.

Keywords: Hip fracture,economic evaluation,multidisciplinary rehabilitation
Subject: Health Sciences thesis

Thesis type: Doctor of Philosophy
Completed: 2014
School: School of Health Sciences
Supervisor: Associate Professor Michelle Miller and Professor Julie Ratcliffe