MS research update - 30 October 2009
- Long-term use of FES strengthens nerve pathways and improves independent walking
- People with MS at greater risk of bone fractures
- Can identification of risk factors for MS help us predict it?
- Continence problems have an emotional and physical impact on people with MS
Long-term use of FES strengthens nerve pathways and improves independent walking
In MS, damage to the nerves in the central nervous system means that messages passing from the brain via the spinal cord are interrupted. One of the problems resulting from this imperfect transmission of messages is dropped foot - the inability to lift the foot and toes when swinging the leg forward to walk. Functional electrical stimulation (FES) is a device that is used to help people with dropped foot. It works by sending electrical impulses to the nerves in the affected muscles, causing movement.
The present study aimed to determine whether long-term use of FES improves the transmission of messages from the brain along the spinal cord when the stimulator is not used. Of the 36 people who took part in the study, 26 had progressive conditions such as MS. All of the participants used an FES device to correct dropped foot for a period lasting between 3-12 months.
A series of tests were conducted, before and after the period of FES use, to measure the speed of muscle contractions as either the brain or the muscles underwent different forms of stimulation. All measures showed improvements following long-term use of FES suggesting that regular FES use had strengthened the 'pathways' along which nerve messages were travelling. Furthermore, significant increases in independent walking speeds were observed when the stimulator was not used.
Everaet DG, Thompson AK, Chong SL, et al.
Does functional electrical stimulation for foot drop strengthen corticospinal connections?
Neurorehabilitation and Neural Repair 2009 [Epub ahead of print]
Medline abstract
People with MS at greater risk of bone fractures
Previous research has shown that people with MS have a lower bone density than the general population. This puts them at greater risk of developing osteoporosis, a progressive condition that causes the bones to become thin and brittle, making them more prone to fractures. The present research uses data from NARCOMS - a US-based voluntary, national, self-report MS register - to investigate whether people with MS are at greater risk of fractures relating to or caused by osteoporosis.
Among responders to a questionnaire, 27.2% reported low bone mass and 15% reported history of a fracture after the age of 13. The responses also revealed that a high proportion also had more than three of the clinical risk factors associated with fractures in MS, nominally: low bone density, low levels of physical activity, falls in the last year, smoking, family history of osteoporosis and impaired mobility. Participants also submitted information about their use of calcium and vitamin D supplements.
The study authors conclude that many people with MS are at high risk of osteoporotic fractures and that many of them are not taking calcium or vitamin D supplements.
Marrie RA, Cutter GA, Tyry T, et al.
A cross-sectional study of bone health in multiple sclerosis.
Neurology 2009; 73(17): 1394-8.
Medline abstract
Can identification of risk factors for MS help us predict it?
Predicting susceptibility to MS has significant implications for future diagnostic and management processes. In recent years, research has indicated that certain genetic and environmental factors can influence an individual's level of risk for developing MS. But as yet, few attempts have been made to incorporate these risk factors into a framework that would enable us to accurately predict an individual's risk of developing the condition.
In the present study, researchers brought together the genetic and environmental factors that are known to influence the risk of developing MS and scored them according to level of influence they are thought to exert. The risk matrix which incorporated information about particular genetic and environmental factors such as smoking and exposure to sunshine, was applied to 2215 people with MS and 2189 healthy controls, and subsequently validated in four other groups.
Whilst some modest predictions were accurate, the proposed risk matrix fell short of proving itself a useful clinical tool that could accurately predict a diagnosis of MS in a clinical or research setting. However, the study did show the promise that such predictive models hold in terms of future development.
De Jaeger PL, Chibnik LB, Cui J, et al.
Integration of genetic risk factors into a clinical algorithm for multiple sclerosis susceptibility: a weighted genetic risk score
Lancet Neurology 2009 [Epub ahead of print].
View abstract
Continence problems have an emotional and physical impact on people with MS
Continence problems are frequently experienced by people with MS and can have a significant impact on their quality of life. Many studies have focused on the frequency and nature of continence problems in MS, but few have examined the impact such symptoms can have on the person as a whole.
This Australian study describes the prevalence and impact of bladder and bowel dysfunction on quality of life in people with MS living in the community. Of the 73 people who took part in the study, two-thirds were bothered by urinary frequency (needing the toilet more than eight times a day) half reported urinary incontinence, and 14% reported bowel incontinence. When asked to describe how hey were affected by urinary problems, 31% described the emotional impact, 22% explained that it prevented them from doing household chores and 28% said it deterred them from participating in physical activities.
The results of the study further emphasise the importance of effective identification and management of continence problems in people with MS.
Khan F, Pallant JF, Shea TL, et al.
Multiple sclerosis: prevalence and factors impacting bladder and bowel function in an Australian community cohort.
Disability and Rehabilitation 2009; 31(19): 1567-76.
Medline abstract