Exercise and Motor Training in People with Parkinson's Disease: A Systematic Review of Participant Characteristics, Intervention Delivery, Retention Rates, Adherence, and Adverse Events in Clinical Trials
There is research evidence that exercise and motor training are beneficial for people with Parkinson's disease (PD), and clinicians seek to implement optimal programs. This paper summarizes important factors about the nature and reporting of randomized controlled trials of exercise and/or motor training for people with PD which are likely to influence the translation of research into clinical practice. Searches identified 53 relevant trials with 90 interventions conducted for an average duration of 8.3 (SD 4.2) weeks. Most interventions were fully supervised (74%) and conducted at a facility (79%). Retention rates were high with 69% of interventions retaining ≥85% of their participants; however adherence was infrequently reported, and 72% of trials did not report adverse events. Overall, the labor-intensive nature of most interventions tested in these trials and the sparse reporting of adherence and adverse events are likely to pose difficulties for therapists attempting to balance benefits and costs when selecting protocols that translate to sustainable clinical practice for people with PD. 1. Introduction In recent years there have been an increasing number of randomized controlled trials assessing the effects of exercise and/or motor training in people with Parkinson’s disease (PD). Overall, these trials support exercise and motor training as beneficial in improving walking, balance, muscle strength, and the performance of functional tasks in people with mild-to-moderate PD [1–11]. In order for findings from this research to be of general benefit to people with PD, therapists need to be able to translate the protocols used in the research into clinical practice [12]. Evidence-based practice aims to incorporate and apply high-quality clinical research findings in clinical policy and practice [13, 14]. However, this can be a challenging task as health practitioners may find it difficult to assess, interpret, and implement research evidence [13]. While evidence about beneficial outcomes is paramount in therapists’ decisions to implement a particular intervention, there are other factors that affect how the overall impact of the intervention is interpreted and its potential for widespread clinical application [13–17]. For example, therapists need to consider how the characteristics of participants included in a trial may affect their decision regarding the applicability of the trial intervention with their patients [14]. It is likely that the way in which the intervention was applied in terms of its duration, level of supervision, delivery (i.e.,
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