Background
Approximately 2 - 5 % of all cases of multiple sclerosis (MS) are diagnosed in children and adolescents. Although relatively uncommon, pediatric-onset MS differs from the adult form in that it is more aggressive; children have larger brain lesions and more frequent relapses than adults. It is only within the last decade or so that research attention has turned to focus on pediatric-onset MS through such initiatives as the MS Scientific Research Foundation-funded Canadian Pediatric Demyelinating Disease Network.
Physical activity represents one potential avenue for symptom management in children and adolescents. Exercise not only contributes to a healthier lifestyle and reduced risk of many diseases, but, in adults, helps manage MS-related symptoms – easing pain, depression, fatigue, relapse rate and even MS progression (see our previous article on exercise and pain management). Now, research conducted by Dr. Ann Yeh, neurologist at Toronto’s Hospital for Sick Children and director of the MS and Demyelinating Disorders Program, and her team has begun to uncover the positive role played by physical activity in childhood MS. The research was funded by the MS Scientific Research Foundation and the findings were published in the journal Neurology.
The Study
Data for the study was collected at the Hospital for Sick Children in Toronto. Participants were anywhere from 5 to 18 years of age, and had either relapsing-remitting MS (a total of 31 participants) or monophasic acquired demyelinating syndrome (mono-ADS, a total of 79 participants).
Whereas MS is characterized by ongoing demyelination, mono-ADS is caused by a single demyelinating event. The researchers chose this specific disorder to highlight differences between relapsing-remitting MS (where demyelination is ongoing) and a single-event demyelinating disorder. It is important to note that both groups of children had similar levels of physical disability (assessed using the Expanded Disability Status Scale, EDSS).
Once groups were established, researchers assessed and compared physical activity status between individuals with MS and mono-ADS. Physical activity was measured using the Godin Leisure-Time Exercise Questionnaire. Participants were asked how often they performed “strenuous (i.e., running or jogging), moderate (i.e., fast walking), or mild (i.e., easy, leisurely walking)” exercise for 15 minutes or more in a normal week.”
The researchers further compared fatigue and depression between the two groups. Fatigue was measured on the PedsQL Multidimensional Fatigue Scale, while depression was evaluated using the Center for Epidemiological Studies Depression Scale for Children.
The researchers then focused solely on the MS group, testing possible associations between physical activity and fatigue, brain lesion size (as seen by MRI) and annualized relapse rate (the number of MS relapses per year).
Results
Children and adolescents with MS reported lower overall levels of physical activity, particularly strenuous activity, compared to those with mono-ADS. They also reported higher overall levels of fatigue and depression.
Within the MS group, moderate physical activity was linked to overall fatigue scores; those that were less physically active were more fatigued, while the more physically active were less fatigued. Participants with MS who participated in strenuous physical activity also tended to have smaller lesions and fewer relapses than other participants within the MS group who engaged in less strenuous activity.
Comment
Though the extent of physical disability was similar between children and adolescents with MS and mono-ADS, those with MS engaged in less physical activity and were more fatigued and depressed. The authors suggest that the lack of exercise could be due in part to the observed increase in fatigue/depression, to the individual’s perceived physical limitations, or the fact that MS activity (unlike mono-ADS) is ongoing.
It was encouraging to note that children and adolescents with MS who were more physically active tended to have decreased fatigue, lesion size and relapse frequency. However, the study had a cross-sectional design that focused on each individual’s level of physical activity at that particular point in time. Future studies will be needed in order to test whether increasing physical activity (for example, encouraging a sedentary child to become more active) can also reduce symptoms associated with pediatric-onset MS. Physical exercise holds the promise for improving quality of life and, also, potentially reducing MS progression in children, and ongoing collaborative research as part of the Canadian Pediatric Demyelinating Disease Network is expected to fill in the missing pieces of this puzzle.
Source
Grover SA et al. (2015). Lower physical activity is associated with higher disease burden in pediatric multiple sclerosis. Neurology. DOI 10.1212/WNL.0000000000001939