Parkinson's disease and virtual reality rehabilitation: cognitive reserve influences the walking and balance outcome.

INTRODUCTION: Parkinson's disease (PD) is a neurodegenerative pathology characterized by motor and non-motor symptoms that often lead to several impairments. Many studies show the efficacy of different rehabilitation protocols aimed to improve balance and gait functions in PD patients. However, multiple factors may influence rehabilitation outcome. Recently, it has been observed as the cognitive reserve (CR) may influence the rehabilitation outcome, helping to address the patient toward technological or conventional rehabilitation. Our study investigated how CR may affect motor rehabilitation outcomes in PD patients who undergo virtual reality (VR) rehabilitation, aimed at improving walking and balance. MATERIALS AND METHODS: Thirty patients affected by idiopathic PD were enrolled. Patients underwent 12 sessions VR training, over 6 weeks (45 min). Six-Minute Walk Test (6MWT) and Berg Balance Scale (BBS) were used to assess walking and balance, respectively. CR was assessed by Cognitive Reserve Index questionnaire (CRIq). RESULTS: Significant correlations between CR and change from baseline in walking and balance measures were found, with a significant positive correlation between CRIq and 6MWT (r=0.50, p=0.01) and between CRIq and BBS (r=0.41, p=0.04). DISCUSSION: Our results showed that PD patients with higher CR treated with VR improved significantly more in their balance and walking distance than those with lower CR. The current study suggests that VR when aimed to improve balance and walking in PD patients is more effective in patients with higher CR.

The impact of cognitive reserve on the effectiveness of balance rehabilitation in Parkinson's disease.

BACKGROUND: Cognitive reserve (CR) can be considered an active expression of brain resilience in response to a damage. Several studies have shown the influence of CR on cognitive impairment and its relationship with cognitive function in Parkinson's disease (PD). AIM: The aim of the present study was to show if CR influences the effectiveness of balance rehabilitation in PD patients who performed a conventional rehabilitative treatment. DESIGN: Observational longitudinal study. SETTING: Neurology Outpatient Unit, University Hospital. POPULATION: Fifty-three patients affected by idiopathic PD, stage 2-3 at the Hoehn and Yahr Scale. METHODS: Each patient underwent 32 group sessions of conventional rehabilitative treatment. At baseline, patients' CR was assessed by the Cognitive Reserve Index questionnaire (CRIq). The primary outcome was the evaluation of static and dynamic balance modifications, induced by the treatment, through the Berg Balance Scale (BBS), assessed at T0 and T1. Mini Mental State Examination, Unified Parkinson's Disease Rating Scale Part III (clinician-scored monitored motor evaluation) and Brief Intelligence Test were assessed only at T0 and used as descriptive variables. RESULTS: Considering the clinically meaningful change, BBS improved in 26% of patients, worsened in 2% and was unchanged in 72%. BBS score significantly improved in older patients, and in those with lower CRI total score. A significant inverse correlation was observed between changes in BBS and work and education related CR. Patients with lower baseline BBS score showed better improvement in balance. CONCLUSIONS: We found an inverse correlation between CR level and balance improvement in PD patients who underwent conventional rehabilitation: higher improvement in BBS was observed in those with a lower CRI score. This may suggest that patients with higher CRI could benefit from more stimulating types of non-conventional rehabilitation (e.g. robotic, virtual reality). CLINICAL REHABILITATION IMPACT: Rehabilitation should be individually tailored considering CR as a significant variable.