Conclusion

This Chapter includes research that addresses the development stage of the Medical Research Council complex intervention framework. Two new predictive models were developed with some attempt to overcome the limitations

highlighted by the systematic review. The models were simple (consisted of a maximum of six factors) and included factors that could easily be collected in routine clinical practice. The models could be used in clinical audit to identify patients whose actual outcome differs from that predicted or be used to stratify patients in rehabilitation trials. The immediate application of these models was to correct for case-mix in the forthcoming observational study (Chapter 3).

3 Establishing baseline physical activity levels in acute stroke patients

3.1 Introduction

Much of today’s focus in healthcare is on the delivery of evidence-based practice, reflected by the increased number of audits being conducted. Using relevant process indicators of care and effective monitoring systems, it is important to demonstrate the implementation of evidence-based therapies.

Increasing physical activity levels are a major component in stroke

rehabilitation. Physical activity is defined as “any movement of the skeletal muscles of the body that results in energy expenditure.”¹⁰⁰ There is suggestion that early intensive activity contributes to the success of stroke unit care and may improve outcomes.^{101 102} Studies investigating activity levels of stroke patients indicate that these are low and are the proportion of time that the patient spends in activity is low.26 46 103-109 Activity levels between patients and stroke units of different countries vary.^{107 110} Factors that have been used to explain these differences include patient and stroke characteristics, variations in practice and the rehabilitation environment.²⁶¹¹¹

There are a number of different methods that can be used to monitor activity in stroke patients such as observational methods and monitoring devices such as an accelerometer (AC).¹¹² Continuous researcher observation has previously been regarded as the ‘gold standard’ and previous studies have observed stroke patients in a variety of settings including medical centres,¹⁰⁴ stroke

rehabilitation centres^{108 109} and ASUs to establish activity levels.^{26 46 107}

Researcher observation provides the opportunity to study the environment in which the activity occurred and understand more about the inconsistencies between what people say they do and what actually happens.¹¹³ Limitations with this approach do exist in that it is labour intensive and often includes periods when the patient cannot be observed, i.e. when the patient is in the toilet or moves away outside the observation area. Additionally, the potential bias of a researcher being present also needs to be considered.^{46 107} Behavioural

mapping, where time intervals are pre-determined, is an observational sampling method which has been used to establish activity levels in stroke patients and observe objective stroke care processes. Examples of processes which have been observed include the time spent in certain activities, structured therapy and interacting with ward staff and relatives.¹⁰⁷ This method has been used in a number of studies and has proved easy to measure and useful in describing physical activity levels in stroke patients and the environment in which activity occurs.

Accelerometry is the modern day equivalent to researcher observation and is now being proposed as the gold standard. Accelerometers provide a continuous, detailed objective analysis of activity levels and patterns. Accelerometers can be used to collect information about the amount, duration and intensity of upright activity. Uniaxial and triaxial ACs measure the acceleration in a number of directions and quantifies the amount of movement. Although triaxial ACs detect movement in three dimensions, uniaxial ACs are thought to provide more reliable data.¹¹⁴ The activPAL^TM professional (PAL Technologies Ltd, Glasgow, UK) is a monitor worn midline on the anterior aspect of the thigh which has been specifically developed to measure physical activity levels in a range of patients.

It is able to discriminate between sitting/lying, stepping and standing allowing time spent in each activity to be measured. The activPAL^TM has been used in stroke research.^{115 116 112} In one study the primary outcome was the number of upright episodes (standing, transferring and walking). It is recognised that quantifying activity by counts does not describe the pattern of activity and may miss important factors such as the time spent in each upright or sedentary episode and the distribution of these events during the day. Information on these factors would provide a fuller picture of the patient’s pattern of activity and potentially inform the design and implementation of future rehabilitation interventions.

As well as the amount of physical activity the schedule of activity may also be important i.e. how long should the rest periods be between mobilisation sessions.³ The impact of lying down for extending periods of time in stroke patients has been previously questioned.¹⁰⁸ Research into sedentary behaviour, which is characterised by prolonged periods of sitting or lying, is growing.¹¹⁷

Large epidemiological studies have found a strong association between prolonged periods of sitting each day with negative physiological changes,

increased risk of all-cause mortality and cardiovascular-disease.¹¹⁸ One study has shown that breaking up sedentary behaviour with short bursts of activity

significantly reduced cardiovascular disease risk.¹¹⁹ This has resulted in an emerging interest in how sedentary behaviour is accumulated in stroke.¹²⁰

Activity-based rehabilitation interventions such as VEM aim to improve outcome for patients after stroke. However, to be able to assess the future

implementation of effective activity-based interventions in clinical practice, a baseline i.e. what is currently happening with regards to activity needs to be investigated. Therefore, Chapter 3 now presents an observational study which aimed to establish pre-implementation physical activity levels in acute stroke patients. Prior to this study, no observational data for activity levels in acute stroke patients was available for a Scottish healthcare setting. It remains

unknown if activity-based rehabilitation interventions do improve outcomes. To further develop the evidence base, the observational data will be used to assess the relationship between activity levels in the acute stages and functional outcome for patients at three and six months, adjusting the analysis for the factors identified to be predictive of outcome (Chapter 2).

Aim

This observational research aimed to quantify upright physical activity level and describe the pattern of upright activity and sedentary behaviour in acute stroke patients using accelerometry, complimented by process information elicited using a standard behavioural mapping technique (BMT).

The objectives of this observational study were as follows:

• To describe the level and pattern of upright physical activity and sedentary behaviour in acute patients in a Scottish healthcare setting using

accelerometery and a behavioural mapping technique

• To investigate whether researcher observation can be predicted by accelerometery

• To identify the patient and baseline stroke characteristics which determine levels of upright physical activity using regression analysis

• To investigate whether the level of upright physical activity in the acute stages post-stroke is predictive of functional outcome at three and six months using regression analysis

3.2 Methods

A multicentre observational study design was used to establish the level and pattern of upright physical activity in acute stroke patients. Patients were recruited from three ASUs in the West of Scotland. Activity monitoring using researcher observation and accelerometry was conducted for each recruited patient, in the ASU for nine hours on one day between Monday to Friday. The BI was administered at three and six months by telephone interview.

Patients over 18 years of age with a clinical diagnosis of first or recurring stroke admitted to an ASU with either a haemorrhage or infarct within the first 14 days of stroke onset were approached for inclusion. Only patients who, at the time of recruitment, were not planned for discharge were approached. All patients or their nearest relative provided informed written consent prior to enrolment.

Patients were excluded if they had already been recruited to another

rehabilitation intervention study as this may have influenced standard mobility practices. Patients for palliative care were excluded.

Recruitment strategy

The research nurses were informed of the study details and the

inclusion/exclusion criteria. Oral presentations were provided locally; at hospital stroke research meeting groups and Managed Clinical Network Research and Development meeting groups to raise the profile of the research. The Scottish Research Network (SRN) nurse acted as the key contact for each of the hospital sites.

Contact was made daily with the research nurses in order to receive updates on new patients admitted to the ASUs and to assess their suitability for

recruitment. All potential study patients were screened and if eligible, the patient or nearest relative was approached and provided with the study patient/relative information sheet (Appendix 7) 24 hours in advance of any decision to participate being made. Potential participants and/or the nearest relative were also provided with verbal information about the study. The

patient, where able, completed the consent form (Appendix 8). Where a patient was unable to complete the consent form fully and/or eligibly, a witness was sought to overview the recruitment process and verify the patient’s verbal consent. The SRN research nurses recruited patients when the researcher was unable to do so.

3.2.1 Accelerometry

The type of AC used was the activPAL™ professional (PAL Technologies, Glasgow, UK). The main features of the activPAL™ are that it is uniaxial, lightweight (weighs only 15mg), is slimline (only 7mm thick) and can collect and store data continuously for up to seven days. The activPAL™ was used to monitor physical activity between 08:00 and 17:00 for each recruited patient (to align with the monitoring timeframe used in the BMT protocol). The activPAL™ monitor was securely positioned onto the anterior aspect of the patient’s thigh using a PALstickie (double-sided hydrogel adhesive pad) at the start of monitoring. For hemiplegic patients there is some suggestion that ACs can be placed on either the non paretic or paretic side.¹²¹ To ensure consistency in this study the monitor was fixed to the patient’s unaffected thigh. The monitor was removed in the event of washing, bathing or showering or if the patient was attending a Magnetic Resonance Imaging (MRI). The time of monitor removal and

re-attachment was noted. The activPAL^TM has been shown to be a valid and reliable device for measuring step number and cadence in a healthy adult population ^122-124 and in patients with problems such as chronic low back pain.¹²⁵ A recent review suggests that ACs can produce valid and reliable data about the physical activity of patients with stroke.¹²⁶

3.2.2 Researcher observation

Intermittent researcher observation was conducted for each recruited patient between 08:00 and 17:00 in the ASU between Monday to Friday. The researcher employed a well-established BMT;¹²⁷ to enable comparability of results with other studies. This technique involved structured observations, of approximately one minute duration, at 10 minute intervals throughout the day with four, 10 minute, rest breaks scheduled. The monitoring timeframe adopted in previous studies has varied from one day to five days.¹²⁸

The BMT is designed to be unobtrusive, using distance observation where possible, and does not intrude on patients behind closed doors or curtains.

Patients may become aware of the observer, but in this population it is unlikely that they will alter their behaviour in response to observation since many people newly diagnosed with stroke require physical assistance to move.

The BMT procedure used was designed to provide a snapshot of routine activity of acute stroke patients. Due to the short length of patient stay in the ASUs the use of a longer monitoring timeframe observation period was considered

impractical. Training in mapping procedure was provided by the author of the protocol.¹²⁷ The type of motor activity, patient location and the people present were recorded on a paper case report form (CRF) at each time interval. Ten motor activity, 14 person present and five locations categories (bathroom, bedroom, hall, therapy area or off ward) were used (Table 3-1). Patient’s privacy was respected and activity behind closed curtains was not observed and patients were not followed off the ward. In such instances, information from periods where the patient could not be observed was determined by asking the patient or staff member as soon as they became available again and was noted as unobserved if unobtainable.

Table 3-1 Motor activity and person present classifications

Motor activity Person present

No active motor (supine or side-lying) Alone

Sit support in bed Medic

Sit support out of bed Nurse 1

Hoist transfer Nurse 2

Roll and sit up Nursing assistant 1

Sit no support Nursing assistant 2

Transfer feet on floor Physiotherapist

Stand Occupational therapist

Walk Speech and language therapist

Stairs Family

Patient transport Interpreter

Other members of multidisciplinary team Other

3.2.3 Data collection, processing and storage

Information on patient demographics, stroke characteristics and the time of first mobilisation were collected prospectively from patient case notes. The findings from the systematic review and predictive modelling presented in Chapter 2 informed the baseline factors that should be collected. The National Institutes of Health Stroke Scale (NIHSS) and modified Rankin Scale (mRS) assessments were conducted on the day before the observation or on the day of observation. Other baseline factors included level of consciousness; muscle power and gait (all using the sub-section of the SSS) were recorded. The treating physiotherapist assessed the patient’s functional mobility using the Mobility Scale for Acute Stroke (MSAS) on the day before the observation (+/- one day). Patients were followed up using the BI at three month and six months by telephone interview. Telephone

assessment of function with the BI has been shown to be a reliable in comparison to a direct face-to-face assessment.¹²⁹

Contact information was collected from the patient, nearest relative or case notes for the purposes of follow-up. This contact information was kept

separately from the CRFs and was treated as highly confidential in a locked area in an office at all times. On discharge, the patient’s general practitioner was advised in writing of the patient’s involvement in the study. The researcher contacted the person who provided consent for involvement to the study to arrange a convenient time to conduct the three month follow-up telephone interview. Patients recruited to the study were provided with a unique identification number (ID) which was used when completing the CRFs.

Completed observed motor activity CRFs were submitted via fax within one week of completion of the day of observation to a specialist centre in Melbourne for processing. The CRFs did not contain any patient identifiable information. The CRFs were converted and saved as a digital image using Teleform^TM software, checked visually and uploaded to a database. The data underwent computer logic testing with data queries being sent via email by the centre’s

administrator. The database was transferred electronically on completion of patient recruitment. Data from the activPAL™ monitors were downloaded to a password secured computer using the software package (activPAL™ Professional Research Edition, version 5.8.50). The CRF folder was stored locally in a locked cabinet and office. Data from baseline CRFs were inputted into a database on the day after monitoring. The CRFs containing the patients contact details were held in a separate folder and locked cabinet. Paper based data will be stored until June 2016, five years from study completion.

3.2.4 Ethics and management approval

The study was granted ethical approval from Scotland A Research Ethics

Committee on 22^nd July, 2010 and subsequent requests for management approval were granted by NHS Greater Glasgow and Clyde Research and Development on 6^th September, 2010 and NHS Lanarkshire Research and Development on 1^st October, 2010. To allow access to the study sites honorary contracts with each of the health boards were applied for and granted on 1^st October, 2010 and 29^th November, 2010. An audit of this study was conducted by the sponsor, NHS Greater Glasgow and Clyde Research and Development, on4^th January, 2012.