The role of training intensity in outpatient rehabilitation of people with Parkinson's disease: A retrospective cohort study of disability progression with 4-month follow-up

Background and aims. Rehabilitation has been shown effective at improving functional abilities of people with Parkinson’s disease (pwPD), through task-oriented and aerobic training, though the exact role of exercise intensity has not yet been determined. The study is aimed at evaluating the impact of different intensity rehabilitation protocols on the short and medium term progression of disability in pwPD. Methods: Using a retrospective cohort study design, the medical records of pwPD who consecutively underwent task-oriented outpatient rehabilitation from 2008 to 2016 at a University Hospital were retrieved. Subjects were considered eligible if they: a) had undergone a single cycle/year of gait and balance training, b) had stable drug therapy during the whole study period, and c) the UPDRS II subscore was available both at the baseline, at the end of treatment and 4 + 2 months after. The UPDRS part-III, TUG test, 6MWT, FOG-Q, Falls Efficacy Scale (FES) and PDQ-39 were also looked for as secondary outcome measures. Results: Eighty out of 420 records met the eligibility criteria. A Low-Intensity (LIT) (39 cases) and a High-Intensity Training (HIT) (41 cases) group were defined according to a total training duration of less or more than 1000 minutes, respectively. HIT group included a greater rate of responders than LIT (65% cases with a meaningful gain in the UPDRS II, vs 35%; Chi2:3.8;p=.04). At variance with the LIT group, HIT subjects also showed a persistent improvement in UPDRS scores (F:14.5;p<.0001) and in FES (F:6.7;p=.002) at the 4-month follow-up. No significant between-group differences were found comparing TUG, 6MWT and PDQ-39 changes. Conclusion: A total training duration of 60/90 minute/session per 20 sessions of task-oriented and aerobic training is recommended in pwPD, in order to ensure a clinically meaningful and persistent reduction of their disease-related disability