BALTiC Study: A Feasibility Analysis of Home Based BALance Training in People With Charcot-Marie-Tooth Disease

A recent, unpublished focus group study of people with CMT found that they reported more falls than healthy people. They reported problems walking on uneven surfaces, difficulty getting off the floor and a necessity to consciously think about every step to avoid falling while walking (GM Ramdharry et al., 2015). A retrospective survey of people with CMT found that 89% of the 94 respondents reported falls to the ground. Half of them reported falling at least once a month with 5% falling every day (Ramdharry et al., 2011). We have just completed an exploratory study of factors predicting falls risk. Preliminary analysis of prospective falls data for 32 people over 6 months showed that they fell a median of 4 times (range 0 - 54 falls) and functional balance performance may be predictive (Ramdharry et al., 2015). A study of people with CMT1a found that sensory impairment increased visual dependence for a static balance task (van der Linden et al., 2010). There has only been one small study of balance training in people with CMT, comparing a novel rehabilitation device with more traditional exercises (Matjacić and Zupan, 2006). Both interventions showed improvement in functional balance scores. Studies of proximal strength training in CMT have shown improvements in walking parameters (Chetlin et al., 2004; Lindeman et al., 1995), but the effect on balance has not been explored. Because of the mixed sensori-motor presentation of people with CMT, a combined approach of multi-sensory balance training and proximal strengthening will be delivered. A home-based model has been proposed as CMT is a life-long condition that needs to be managed by the individual outside of the medical or therapy environment.

STUDY DESIGN & JUSTIFICATION A single blinded randomised controlled design has been chosen in this feasibility study. The intention is to see if there is an effect of the intervention to later be explored in a larger randomized controlled trial. A blinded assessor will measure balance performance prior to randomisation and following the 12 weeks of either intervention or control. They will also undertake qualitative interviews prior to randomization and following final measurement session. Interviews will inform the intervention and its acceptability. All participants will receive a falls assessment and falls education. Following randomisation, participants will either receive the 12-week intervention or control period. The intervention will include a holistic programme of physiotherapy including strength training of muscle groups unaffected by the condition and multi-sensory exercises to target balance. The program will be delivered by a physiotherapist trained in delivering treatment under the principles of self-management. Exercises will be carried out by the patients in their own homes and monitored by the research physiotherapist, progressing as appropriate. Those randomized to the control arm will receive monitoring telephone calls throughout this 12-week period.

RECRUITMENT Patients will be recruited from outpatient neurology clinics at Queen Square which specialise in the diagnosis and management of CMT. Patients who fit the inclusion criteria will be approached and the trial will be described to them. Written information will be provided and arrangement made for a way to make contact once they have decided about whether they wish to proceed with screening. All patients who agree to proceed will go through a screening which will take place over the telephone. Those who pass screening will be provided with falls diary postcards or arrangement for falls diary emails, which they will be asked to monitor and report for one month. A sample will be invited for a qualitative interview. Arrangement will be made for them to attend a baseline measurement session, falls assessment, and falls education following the month-long falls monitoring.

Measures will include:

Patient reported questionnaires of balance confidence, mood, walking ability and physical functioning 10m walk test / 6 minute walk test Berg Balance Scale Bruininks Oseretsky Test (BOT) BESTest Functional balance tests using force plate and movement analysis equipment Strength testing of the lower limbs and hands Charcot Marie Tooth Examination Score (CMTES) A block randomisation will occur following the baseline measurement and falls education session with allocation either being to a control arm or an intervention arm. This will be done by the PI or research physiotherapist who will remain un-blinded. Contact with the blinded assessor will cease until the final measurement session 12 weeks later.