Exercise as it relates to Disease/Effects of cognitively challenging Parkinson's Patients during exercise

Critique of Article: The Effects of Highly Challenging Balance Training in Elderly With Parkinson's Disease: A Randomized Controlled Trial by Conradsson D, Lofgren N, Nero H, Hagstromer M, Stahle A, Lokk J, et al. Neurorehabil Neural Repair. 2015;29(8):827-836.

What is the background to this research?
Parkinson’s Disease (Parkinson’s) is a progressive neurodegenerative disorder resulting from the death of dopamine neurons in the substantia nigra, which is responsible for the coordination of movement. Parkinson’s is characterised by a range symptoms, including motor impairments such as balance problems and gait abnormalities. As gait and balance abilities deteriorate with disease progression, there is an underlying fear of falling, which results in the decline in physical activity, and ultimately a reduction in quality of life. Therefore, physical activity is important in managing disease progression, especially if it requires simultaneous engagement of cognitively demanding tasks (dual-tasking) due to its neuroprotective benefits. Furthermore, research indicates that training programs for Parkinson's needs to be specific; progressive; and challenging the participant's capacity limits in order to be effective. Based upon that premise, and critical aspects involved in balance control, the authors of this study have developed a novel conceptual framework for balance training, known as the HiBalance program.

Where is the research from?
The study was completed at the Karolinska Institute and Karolinska University Hospital, the largest Swedish medical university involved in teaching and academic research. The lead author, Dr. David Conradsson is a lecturer at the Karolinska Institute and a widely published academic specialising in neurological disorders, particularly Parkinson's.

The study received financial funding from several research and foundations associated with the Karolinska Institute and Parkinson’s groups. However, there were no references to the level of involvement regarding the role of these funders.

What kind of research was this?
The study was a randomised controlled trial which is considered to be one of the most rigorous scientific methods of hypothesis testing available. However, the study was not a blinded trial, as the assessors were unmasked during post-test assessments, and so bias was a possibility during physical testing.

In comparison to other studies examining the effects of highly challenging balance programs by way of adding resistance and varying surface conditions; or dual-tasking requirements, the current study's sample size is notably larger but assessed outcomes comparable. The clinical tests used to assess balance and gait are also widely used in Parkinson's literature and recommended. Aside from one qualitative study, there are no other studies examining the application of the HiBalance program apart from the authors themselves, who are also the developers of the program.

What did the research involve?
The study involved 100 elderly patients with mild to moderate Parkinson’s, presenting with impaired balance. It evaluated the short-term effects of the HiBalance Program compared with usual care, and whether any effects transferred to everyday living. The intervention group (HiBalance) had 51 participants and the control group (usual care) had 49 participants. The intervention was implemented by two trained physiotherapists, and was ten weeks in duration, with three 60 minute sessions per week.

The methodology of the study was prepared in accordance with the CONSORT Statement, which is an evidence-based standard for reporting randomised trials that promotes transparency and allows for possible replication. Despite being well prepared and adhering to the CONSORT Statement, the intervention may be difficult to replicate as it is based upon a novel framework which is broad in nature, and required the physiotherapists to have undergone specific training regarding the underpinning theory and practical application of same.

What were the basic results?
The intervention group had statistically significant improvements in balance performance and gait velocity. There was also statistically significant improvements in secondary outcomes where there was an increase in physical activity levels and better self-perceived disability scores with respect to ADLs. However, there was no changes in concerns about falling. The control group did not see any statistically significant improvements in any categories. In fact, there was a decline in physical activity levels. The authors placed emphasis on the resulting increase in gait velocity as it is usually a vital indicator of health in older adults. Other gait characteristics were somewhat disregarded as there were no statistically significant changes; although the authors considered the small increase of step length (0.04m) to be an indication that the intervention efficiently targeted gait impairments on the basis that step length has rarely been improved in training interventions. However, there has been evidence that step length can be increased with specific training in patients with Parkinson's.

Although the secondary outcomes showed improvement, the results must be cautiously considered as to whether they represent any transferrability to real-life settings. The increase in physical activity levels between the intervention and control group were very small in absolute terms. Additionally, the baseline and post-intervention figures of the intervention group had higher physical activity levels in the first instance. The improvement on perceived disabilities affecting ADLs did not reach the minimal clinical important difference either. The authors disregarded the unchanged results relating to concerns about falling as research at that time found no exercise effects on concerns about falling. Since then, research has found that fear of falling can be improved with exercises involving high motor complexity.

What conclusions can we take from this research?
Overall, the study was quite robust and had considered its limitations thoroughly. It is evident that the HiBalance intervention improved balance performance and certain gait outcomes, with some possible positive transfers to everyday living in a very specific population with Parkinson's. The recruitment of subjects through advertisements meant that the sample consisted predominantly of those interested in balance training and seeking improvements. It must also be noted that intervention was pertaining to the elderly with mild to moderate disease classification and could walk unassisted indoors, and may not elicit the same effects for those with more severe impairments. Lastly, the intervention was short-term, and it would be worthwhile to investigate the long-term effects of the intervention given the progressive degenerative nature of Parkinson's.

Practical advice
The HiBalance program is a novel framework that is still being tested in its application in clinical settings, and as such it is inappropriate to infer any practical advice from the study. However, it provides insight to treating specialist who have elderly Parkinson's patients with mild to moderate balance symptoms in structuring and varying their exercise programs for the purpose of improving balance and gait performances.

It is advisable for any individuals with Parkinson's wishing to undertake new physical activities to consult their treating specialists.

Further information/resources
Parkinson's Support Group in Australia

Systematic review on exercise and balance in Parkinson's across all disease stages. Further information regarding HiBalance program: study protocol and feasibility report.