Introduction
Motor neurone disease (MND) is a debilitating, life-limiting condition characterised by the loss of motor neurons in areas including the cerebral cortex, brainstem, and spinal cord, manifested by upper and lower motor neurone symptoms (Shook & Pioro, 2009; Ward et al., 2010). As motor neurons deteriorate, symptoms manifest in a multitude of ways, including: respiratory compromise, spasticity, atrophy, fatigue, dysphagia, dysarthria and progressive weakness in the trunk, bulbar muscles and limbs (Petri & Meyer, 2011).
MND is an overarching term to describe a number of conditions that include amyotrophic lateral sclerosis, progressive bulbar palsy, progressive muscular atrophy, and primary lateral sclerosis. Some are not fatal, and progress much slower than others, for example, primary lateral sclerosis (Petri & Meyer, 2011; MNDA, 2015). However, for the purpose of this study, the author is referring to the more progressive forms of MND, in particular the most common form, amyotrophic lateral sclerosis (ALS). ALS is often rapid in progression, leading to death for the majority of patients within two to five years (Petri & Meyer, 2011; National Clinical Guideline Centre, 2015). It is estimated that, at any given time, 5000-7000 people are living with MND in the UK, and approximately 1100 people are diagnosed nationally every year (Gent,2012; National Clinical Guideline Centre, 2015).
The Motor Neurone Disease Association (MNDA) estimates that 80% of people diagnosed with MND will require the use of a wheelchair (MNDA, 2015b). Owing to the rapid progression of MND, quality of life is suggested as a primary goal for patients (Lewis & Rushanan, 2007) and the provision of a wheelchair can facilitate an improvement in quality of life and independence. With this in mind, the National Clinical Guideline Centre (2015) recommend that patients are referred for assessment by a specialist wheelchair centre as soon as possible. It has also been suggested that, even if a patient is mobile, provision of a wheelchair can assist with energy conservation, and therefore referral should happen in a timely way (Lewis & Rushanan, 2007).
However, there are approximately 1.2 million wheelchair users in the UK with services funded and run differently, and services provided for patients can vary from one area to another (NHS Improving Quality, 2014).
To facilitate an improvement in services, it is suggested that evidence based practice is utilised and implemented into treatment (NHS Improving Quality, 2014; National Clinical Guideline Centre, 2015; MNDA, 2015b). Law & MacDermind (2014) describe evidence based practice (EBP) as a process characterised by an inquisitive practitioner who wishes to develop their practice and that of others. The process starts with a question, followed by appraisal of the evidence, implementation of that evidence (providing it is methodologically sound), and the evaluation of the outcome of the intervention. EBP is becoming more prominent within services and within practice, and the Health and Care Professions Council (2013) suggest that Occupational Therapists engage in EBP, evaluate their own practice systematically, and participate in the evaluation of that evidence. Other academics have suggested that, because of the amount of research published, it is not effective to simply read research, and that therapists require tools to be able to critique the quality of the research (Glasziou et al., 2007). This is further supported by Melnyk and Fineout-Overholt (2011) who suggest that to be an effective evidence based practitioner, one needs to find, critically appraise, and use, the best evidence in clinical practice.
Methodology
The objective of this review is to identify and critically appraise research literature to attempt to answer a pertinent question within practice. The Population, Intervention, Comparator, Outcome (PICO) principle (Table 1) was utilised to formulate an appropriate and focused question (Law & MacDermind, 2014):
Would earlier powered wheelchair provision improve quality of life or independence in adults diagnosed with rapidly deteriorating Motor Neurone Disease?
Table 1: PICO
P |
Motor Neurone Disease |
I |
Powered wheelchair |
C |
Current practice |
O |
Improved quality of life / Independence |
A search of the following databases between the years of 2000-2015 was conducted: AMED, CINAHL Plus, MEDLINE & SocINDEX, using combinations of the search terms listed in Table 2.
Table 2: Search Terms
Motor Neurone Disease or Amyotrophic lateral sclerosis
|
AND |
Wheelchair or Powered Wheelchair |
AND |
Quality of Life or Independence |
This search returned 121 articles and, after title and abstract analysis and deletion of duplicate articles, 28 articles were deemed appropriate for initial analysis, and a further 11 articles were located via a manual search of the literature and reference lists of relevant articles. From this analysis, a total of 11 articles were deemed appropriate for full critique and discussion (Flowchart 1). Exclusion criteria included case reviews, opinions or articles addressing other topics with wheelchairs or MND as a by-product.
Conducting research with a group of patients facing imminent deterioration in health and well-being and likely death in a very short space of time is difficult. The conducting of randomised controlled trials would be unethical in a group of patients who require provision, as a control group would require withholding of equipment; therefore research of this standard is not available. Furthermore, as a result of the rapid deterioration of the condition, the majority of research conducted is of convenience, because it would be very difficult to conduct the necessary research in a timely manner. Consequently studies using convenience samples were included within this literature review. While they returned two systematic reviews and two cohort studies, the majority of other papers available were convenience samples (Table 3).
Table 3: Hierarchy of Evidence
Level 1 |
Systematic reviews (n=1) |
Level 2 |
Cohort studies (n=2) |
Level 3 |
Convenience sample (n=8) |
Level 4 & 5 |
(n=0) |
Flowchart 1: Article Inclusion (Liberati et al., 2009; Aveyard, 2010)
Records identified through database searching |
Additional records identified through other sources |
Records after duplicates removed |
Abstracts screened |
Records excluded |
Full-text articles excluded |
Full-text articles assessed for eligibility |
Studies included in literature review |
Literature Review
Powered wheelchairs and MND
Mobility is considered an essential component of participation, activity and quality of life, and increased mobility has been shown to have a positive impact on independence (Sonenblum et al., 2008). Powered wheelchairs are routinely issued to patients with MND as their illness progresses, while manual wheelchairs are provided in the earlier stages of the condition. However, in the author’s experience, this can cause issues as the disease progresses when patients become too debilitated to function in their manual wheelchair, and require the provision of powered mobility. Due to waiting times for provision or, indeed, where the disease has progressed too far, powered provision can be too late to provide any true independence or quality of life.
A systematic review conducted by Arbesman & Sheard (2014) looked at occupational therapy interventions for people with ALS between 2003-2011 and found that there is limited research conducted around the area of powered wheelchairs and ALS. The authors concluded that there is limited evidence that people with ALS are comfortable or satisfied with the use of their powered wheelchair. The authors further stated that there is limited evidence that powered wheelchairs enable better interaction and involvement in the community. The authors suggested that the selection of powered wheelchairs must be taken with the progression of the disease in mind, and that appropriate add-ons, such as dual control and tilt in space, should be utilised.
An interesting study conducted by Ward et al. (2010) suggested that provision of appropriate functions on the wheelchair, including the provision of powered tilt in space and attendant controls, are an important consideration. Ward administered a questionnaire to a convenience sample of 32 people with ALS and issued with a powered wheelchair in the United States of America (USA). Provision was handled in clinic, and questionnaires were sent retrospectively. Clinics and provision operate slightly differently in the USA; for example, within this study patients attended clinic with a therapist and equipment supplier, and were afforded the opportunity to test drive numerous powered wheelchairs. Results from Ward and her team demonstrated that initial use of the powered wheelchair and functions was low. However this increased over time with the patient using the wheelchair and the facilities more often. Unfortunately the research does not indicate the time interval between provision and an increase in use. This may be due to difficulties in measuring because of differences in disease progression between patients. It must additionally be noted that funding and provision systems in the USA are very different from those in the UK, and that provision of such expensive high end wheelchairs as those used in this study are unlikely to be funded via the NHS (average cost per wheelchair $26,404).
In a British study, Rolfe (2012) conducted a robust convenience sample of 62 patients who had been provided with a wheelchair from the Oxford MND centre between 2007 and 2010. The purpose of the research was to attempt to aid wheelchair services by providing a timeline of likely need for provision. The author found that the average time for a limb onset diagnosed patient from diagnosis to require a powered wheelchair was 25 months compared to 12 months for a patient diagnosed with bulbar onset. This research demonstrates the need for wheelchair services to be made aware of the Amyotrophic Lateral Sclerosis Functional Rating Scale (ALSFRS) score as this, in combination with knowledge of the onset site, can help to predict the rate of change. In turn this would help services plan to meet individual needs, especially considering the much shortened time scale for patients with bulbar onset.
Rolfe further demonstrated that time between provision of a manual wheelchair and a powered wheelchair is often short (4-11 months). Consequently patients tend to have to revert to a waiting list for powered chair provision through wheelchair services in a relatively short space of time after their manual chair provision. Rolfe (2012) suggests that, for patients with a rapidly deteriorating condition such as MND, a new approach which separates this group and speeds provision should be considered.
There is very limited research evidence available on this topic. Rolfe has demonstrated the need for timely provision and for therapists and wheelchair services to be more aware of the diagnosis type and functional abilities of the patient, and the subsequent positive impact on provision. It must be noted however that this research was conducted through a specialist MND centre and not through a standard NHS wheelchair service. Nonetheless, it is important that wheelchair services link with services such as these to facilitate best practice development and further enhance skills and abilities. Furthermore, this research utilised a convenience sample of patients, and further research needs to be conducted on a wider scale taking into account a number of NHS-provided services.
An earlier study conducted in the USA looked at user characteristics and preferences of patients diagnosed with ALS. Trail et al. (2001) found that powered wheelchairs provided a greater sense of well-being and improved independence for patients, in comparison with those using a manual wheelchair. A similar, but larger (n=63) and more recent study by Gruis et al. (2011), also in the USA, looking at ALS patients’ use of, and satisfaction with, the use of assistive technology, found that patients answered positively to how well the powered wheelchair worked. However, overall they were only moderately satisfied with their wheelchair, whether manual or powered. The authors concluded that issues relating to manoeuvrability and size of the powered wheelchair may have a detrimental effect on patients’ satisfaction with its use, even though many desirable functions are available on powered wheelchairs as opposed to manual wheelchairs. Wheelchairs were not the main focus of this research, and it must be noted that it was conducted as a survey of patients’ use of all assistive devices, therefore patients may naturally have different preferences between one piece of assistive technology and another. Furthermore it must be noted that the range of responses from patients in the survey when questioned regarding their satisfaction with their powered wheelchair was between 5 and 10 with a median of 8 (10 being extremely satisfied).
As wheelchairs were not the main focus of this research, reliability must be questioned because patients were asked to rate a number of assistive devices, and they may have inadvertently compared devices and potentially provided lower scores than they would have otherwise given.
Although limited in their methodology, these two papers indicate the importance of powered wheelchairs for patients diagnosed with ALS and indicate that, overall, patients responded positively to the use of their powered wheelchair, and found that powered wheelchairs provided an improved sense of well-being and independence.
Powered wheelchair provision and independence / quality of life
Due to the limited amount of research into the area of MND and wheelchair provision, it was necessary to take into consideration the effect of powered wheelchair provision on quality of life and independence in other conditions. A convenience sample study conducted by May & Rugg (2010) in the UK examined 20 wheelchair users’ perceived improvement in occupational performance, quality of life, and satisfaction with their powered wheelchair provision. The authors found that patients perceived an increase in the quality of their lives as well as improvements psychologically and functionally after provision. However, this study was small in size and included a number of different conditions, making results difficult to generalise. However, since the authors utilised a standardised tool as well as qualitative methods, the research could be reproduced on a condition-specific, larger scale.
In other studies relating to use of powered wheelchairs and quality of life, positive outcomes have been found. Pettersson et al. (2007) conducted a study of 32 stroke patients at the point of delivery of a powered wheelchair as well as 3-5 months after provision. This research, conducted in Sweden, used a structured questionnaire and standardised outcome measures. Utilising the Psychosocial Impact of Assistive Devices Scale (PIADS) (Day et al., 2002) the authors demonstrated that provision of a powered wheelchair has a positive outcome on quality of life for the majority of participants (n=91%). However, the EuroQol-5D scale, a self-completed quality of life measure developed by EuroQol (EuroQol Group, 1990) showed that all participants within the project felt their quality of life regarding mobility had been unchanged, which contradicted the findings from the PIADS. This research would appear robust in its methodology taking into account a number of outcome measures and questions. However, with the findings contradicting themselves, it would appear that participants may have been confused by what was being asked of them, compounded by the use of two different outcome measures.
Interestingly additional studies in Nordic countries have found positive results. Löfqvist et al. (2012) conducted a prospective cohort study via structured interviews at provision, four months, and one year follow up of 47 patients who were prescribed powered wheelchairs or powered scooters in Sweden. Utilising an outcome measure designed specifically for Nordic countries, they found that one year after provision, 50% of people reported being more independent than they were at provision. It must be noted that after one year only 34 participants remained in the study, and the majority of these were male (n=23). Another consideration is that cultural differences as well as service provision and legislative differences may make comparisons to provision in the UK difficult. For example, in these Nordic papers, powered wheelchairs and powered scooters are used interchangeably and are issued by local therapists, a practice which does not occur in the UK. Nevertheless, positive outcomes with regard to independence and quality of life have been found throughout the research and therefore show the potential effect of powered wheelchair provision.
An earlier study found that provision of powered wheelchairs facilitated an increase in independence among the 124 participants, and the participants placed a high value on this increase in independence. In this study Frank et al. (2000), used a convenience sample of patients in north west London to investigate problems and benefits of provision of powered wheelchairs. The authors found that powered wheelchair provision allowed for reduced dependence on care givers. However, it must be noted that this study was conducted when powered wheelchair provision was in its infancy and models have changed drastically in the last 15 years. A more recent study by Frank et al. (2010) examined carers’ and families’ experiences after provision of a powered wheelchair. Using a structured telephone interview of 64 patients, they found that powered wheelchair provision provided the patient with more independence and freedom, and also allowed the caregiver to have some freedom. Although published in 2010, this research was actually conducted in 2002, again a time when powered wheelchairs were still in the initial stages of being prescribed within the NHS.
Evans et al. (2007) conducted a qualitative investigation into older adults’ satisfaction with, and use of, powered wheelchairs. Amongst the 17 participants satisfaction varied immensely, with some participants experiencing positive changes since provision, and some not using their wheelchair at all or reporting no positive impact. The qualitative approach to this research appears appropriate and robust: interviews were conducted by the researchers, and analysis was conducted by someone not involved in the research, eliminating a source of bias.
The findings of this paper suggest there are benefits associated with powered wheelchair provision, including increased independence and well-being; however, not everyone finds provision to be of benefit, especially participants with environmental concerns. Therefore careful consideration needs to be taken when providing wheelchairs to balance the patient’s needs, environment and lifestyle with the expensive nature of this equipment and potential for non-use.
Conclusion
The research evidence base around powered wheelchair provision is limited. This points to the requirement for further research and the need to provide evidence that patients receiving assessments and wheelchairs through the NHS and their contractors are being provided with the correct equipment in a timely and holistic way, based on best practice. Currently there are no definitive guidelines on when, or indeed what, would be most appropriate to provide a person diagnosed with MND. However it is clearly agreed throughout studies that provision in a timely manner is essential. Furthermore, early provision can facilitate increased independence and abilities before the deteriorating nature of the disease takes control of the patient's life. In addition, providing a powered wheelchair early in the disease progression along with features that can adapt in the future to enable independent mobility using adaptive aids or for attendant propulsion, means that the person can experience greater quality of life and independence throughout their illness (Ward et al., 2010; Rolfe, 2012).
Referring back to the original question Would earlier powered wheelchair provision improve quality of life and or independence in adults diagnosed with rapidly deteriorating Motor Neurone Disease?, in the main it has been found that provision of a powered wheelchair to patients diagnosed with MND can have a positive effect on their quality of life and well-being. However it is important to set up wheelchairs with appropriate functions and facilities, and to provide them in a timely manner to enable patients to continue to use them as their disease progresses (Ward et al., 2010; Rolfe, 2012). As previously stated, there is a lack of information pertaining to wheelchair use and patients diagnosed with MND and, as such, it was necessary to consider the effect powered wheelchair provision has on patients with differing conditions with regard to quality of life and independence. Again, positive outcomes were found throughout this review with increases in quality of life as well as independence reported (Frank et al., 2000; Pettersson et al., 2007; Frank et al., 2010; May & Rugg, 2010). However one small study found independence and satisfaction to vary significantly between participants, particularly when environmental issues were not taken into consideration (Evans et al., 2007).
It is the opinion of this author that provision of a powered wheelchair earlier in the disease process can facilitate an increase in short term independence and longer term quality of life. This is supported by Lewis & Rushanan (2007) who suggest that patients are able to maintain their independence with the use of a powered wheelchair. Initially that may be with joystick or other specialist controls such as head/proximity controls etc. and, as the patient deteriorates, an attendant control can be added. This is further supported by Rolfe (2012) who concluded that powered wheelchair use in patients with MND allows for appropriate functions to be utilised that are only available on powered models. It is important to consider however that powered wheelchair provision may not always be possible due to environmental and vehicular restrictions, as well as issues with acceptance of equipment. Therefore provision of powered wheelchairs will not be suitable for all patients, and a holistic individual assessment will need to be conducted.
However with current practice tending to lean towards the provision of a manual wheelchair in the initial stages of the disease, as demonstrated by Rolfe (2012), this author would like to propose that a change in approach is adopted whereby, even at the earlier stages of the condition (when patients are still ambulant), they are offered provision of a powered wheelchair which would maximise independence and quality of life and allow for easier progression of controls in the future. This would give patients diagnosed with MND choice, and allow them the benefits of powered wheelchair provision as early as possible.
Service Implications
It is the author’s aim that this study will aid in the implementation of a fast-track system as recommended by the MNDA, where patients diagnosed with all varieties of MND will be assessed within five days and, if deemed appropriate, receive a powered wheelchair within 14 days of referral (MNDA 2015a). This will require close collaboration with wheelchair manufacturers and commitment from all areas of the team. It may be possible for powered wheelchairs with adjustable seat sizes to be pre-bought and stored within the department; however this will obviously require a short-term bulk investment. Taking into consideration the short use that these wheelchairs are likely to receive, wheelchairs could be recycled and this could provide an economic incentive for commissioners.
The implementation of the fast-track system will be aided by the MNDA who, working in partnership with a number of manufacturers, has designed four specifications of wheelchairs for the use of patients diagnosed with MND. These wheelchairs are designed to enable the one wheelchair to be used through the entirety of the disease (MNDA,2015b).
Initially provision would facilitate increased quality of life and independence alongside comfort and, when necessary, can be altered for use with appropriate assistive devices, controls and driving aids with the use of attendant controls. In addition manufacturers of these wheelchairs are able to process orders in a more timely fashion, and facilitate a much improved turnaround of provision. This would naturally aid this author’s goal of provision 14 days from the date of referral, enabling the patient to attain the best quality of life possible.
It is hoped that by the implementation of this change in service provision, patients with MND will experience an improved quality of life and independence that they may not have experienced otherwise.
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