Quality of life and cost effectiveness following the use of Functional Electrical Stimulation (FES) of the peroneal nerve for people with multiple sclerosis

Abstract

Abstract: P1638

Type: LB Poster

Abstract Category: Late Breaking News

Background: There is a large gap in quality of life for people with MS and the general population. FES is an effective intervention for dropped foot reducing falls by 72% (1), with a mean usage of 4.9 years (2). Improving health related quality of life and cost effectiveness are a priority for the national health system in the UK, who have set a cost effectiveness threshold of £20,000(€24,218) per Quality Adjusted Life Year (QALY) under which interventions will be considered.

Method: 45 people with multiple sclerosis (mean age 53, range 40-70) and foot drop completed the EQ-5D-5L (Euroqol) quality of life questionnaire before and after using FES for 20 weeks. Index values were calculated using the latest available value set and checked with the crosswalk value set (3). QALY gain was calculated by multiplying the utility value by the average length of time of FES use, discounted at 3.5% per year. The mean cost minus the expected cost saving due to falls prevention was divided by the QALY gain to give the mean net cost per QALY.

Results: The mean index value before treatment (0.542) was highly significant compared to after treatment (0.656) (t=-4.68, p< 0.001), providing a utility value of 0.114 which works out to 0.542 when extrapolated to 4.9 years. The cost of providing FES for 4.9 years is £3095(€3,742)(1), giving a cost per QALY of £5,705(€6,901). However, it is estimated that the reduction of falls may result in a cost saving of £375(€454) per year, bringing the net cost to £1,256(€1,519) and cost per QALY to £2,316(€2,801).

Conclusion: These preliminary results must be treated with caution as the data used was taken from three different studies. Nevertheless the analysis indicates that FES is associated with improved health related quality of life and is well within cost effectiveness thresholds.

References:

1. Barrett C, Mann G, Taylor P, Strike P. A randomized trial to investigate the effects of functional electrical stimulation and therapeutic exercise on walking performance for people with multiple sclerosis. Mult. Scler. J. 2009;15:493-504.

2.Taylor P, Humphreys L, Swain I. The long-term cost-effectiveness of the use of Functional Electrical Stimulation for the correction of dropped foot due to upper motor neuron lesion. J. Rehabil. Med. 2013;45:154-60.

3. Devlin N, Shah K, Feng Y, Mulhern B, van Hout B, Street L. Health Economics & Decision Science (HEDS) Discussion Paper Series.[cited 2016 Mar 23] Available from:https://www.shef.ac.uk/polopoly

Disclosure: Tamsyn Street has received a grant from the Salisbury Charitable Trust to conduct this work. Ian Swain is Professor of Clinical Engineering at Bournemouth University and is also Clinical Director and a shareholder in Odstock Medical Limited who manufacture the equipment and provide the clinical treatment that is the subject of this research. Paul Taylor holds shares in OML, the manufacture of the device used in this study.

Full text

Quality Adjusted Life Years (QALY) Gain From The Use Of FES For The Correction Of
Dropped Foot Due To Stroke And Multiple Sclerosis Derived Using The Eurool EQ-5L-5D
Paul. Taylor1, 2, 3, Tamsyn. Street1 and Ian. Swain2, 3
1Salisbury NHS Foundation Trust, Salisbury, 2Bournemouth University, Bournemouth, 3Odstock Medical Ltd, Salisbury,
United Kingdom
Introduction
FES is an effective intervention for dropped foot and has a mean usage of 4.9 years1. The National Institute for Health
and Clinical Excellence applies a cost-utility ceiling of £20,000 per Quality Adjusted Life Year (QALY) for an intervention
to be considered. Previously the QALY gain derived from the effect of FES on walking speed was estimated as 0.041,
giving a cost per QALY of £15,406. The aim of this study is to produce a new estimate of QALY gain using the Euroqol
EQ-5D-5L.
Method
45 people with MS (mean age 53, range 40-70) and 26 with stroke (mean age 59.5, range 44-72) who had foot drop
completed the EQ-5D-5L before and after using FES for 20 weeks. QALY gain was calculated by multiplying the change
in EQ-5D-5L utility score by the average FES use time, from the previous long term audit1, discounted at 3.5% per year.
The mean cost of FES provision1 was divided by the new QALY gain to give the mean cost per QALY.
Results
The mean EQ-5D-5L derived utility value pre intervention was 0.542 for MS and 0.498 for stroke. This increased after 20
weeks of FES use to 0.656 for MS and 0.612 for stroke, providing a utility value of 0.114 for both conditions (MS
p<0.001, Stroke p<0.005). Justified by the observation that the mean increase in walking speed due to FES remains
steady throughout the time FES was used, the QALY gain was extrapolated over 4.9 years giving a total gain of 0.542.
From the long term audit the mean cost was £3095, giving a mean cost per QALY of £5,705.
Discussion and conclusions
The new value for QALY gain derived using an accepted health economic assessment indicates that original value
significantly under estimated the benefit of FES to health related quality of life.
1. Taylor P, Humphreys L, Swain I. The long-term cost-effectiveness of the use of Functional Electrical Stimulation for the correction
of dropped foot due to upper motor neuron lesion. J. Rehabil. Med. 2013;45:154-60.
Supported by the National Health Service (UK and OML
IFESS 2017, July 20th-22nd, London