Date Published: February 27, 2018
Publisher: Public Library of Science
Author(s): Franciele Cascaes da Silva, Rodrigo da Rosa Iop, Laiana Cândido de Oliveira, Alice Mathea Boll, José Gustavo Souza de Alvarenga, Paulo José Barbosa Gutierres Filho, Lídia Mara Aguiar Bezerra de Melo, André Junqueira Xavier, Rudney da Silva, Stephen D Ginsberg.
Given the relative importance of cognitive impairment, there was considerable interest in identifying the cognitive profile of PD patients, in order to ensure specific and appropriate therapeutic interventions.
To determine the effects of physical exercise programs on cognitive function in PD patients, compared with the control group.
Medline, Cochrane, Scopus, PEDro and Web of Science (last searched in September 2016).
Randomized clinical trials examining the effects of physical exercise programs and cognitive function in PD patients. Nine studies fulfilled the selection criteria and were included in this review.
Characteristics of the publication, characteristics of the participants, test used for cognitive screening, cognitive domain assessed, tools used to assess cognitive function, characteristics of the experimental intervention, characteristics of the control group, mean results and standard deviation of function cognitive. The PEDro score was used to evaluate methodological quality.
Most eligible studies showed good methodological quality based on the PEDro scale. Studies have shown that adapted tango for PD patients, cognitive training combined with motor training, and treadmill training promote the preservation or improvement of cognitive function in PD patients.
The diversity of cognitive tests used to assess cognitive function and the high heterogeneity identified between the physical exercise programs.
Physical exercise programs promote positive and significant effects on global cognitive function, processing speed, sustained attention and mental flexibility in PD patients, at a mild to moderate stage for patients with a 6-year clinical diagnosis of PD. However, treadmill training performed 3 times a week for about 60 minutes and for a period of 24 weeks produced larger improvements in cognition.
Parkinson’s disease (PD) is a chronic, progressive and multisystem neurodegenerative disease  and has historically been considered specifically as a motor disorder.  However, in the past decades, a wide spectrum of non-motor manifestations of this disease has been recognized. [3,4]
This systematic review was registered under the number CRD42016047788 in the International Prospective Register of Systematic Reviews—PROSPERO and follows the recommendations proposed by the Preferred Reporting Items for Systematic Review and Meta-Analysis: The PRISMA Statement (S1 PRISMA Checklist). 
The primary objective of this study was to assess the effects of physical exercise programs on cognitive function in PD patients, compared to the control group, through a systematic review of randomized controlled trials (RCTs) in the last 10 years. Nine RCTs were analyzed including the effect of various types of physical exercise programs on cognitive function in PD patients in the mild to moderate stage (Hoehn and Yahr) and with disease time around 6 years.
Through this systematic review of RCTs, we found that physical exercise programs promote positive and significant effects on global cognitive function, processing speed, sustained attention and mental flexibility in Parkinson’s disease patients, at a mild to moderate stage for patients with a 6-year clinical diagnosis of PD, such as tango, cognitive training associated with motor training, and treadmill training. However, treadmill training (80–100% of the preferred walking speed) performed 3 times a week for about 60 minutes and for a period of 24 weeks produced larger improvements in cognition.
It is important to consider the impact of impaired cognition on managing motor deficits associated with PD and the important contribution to the general well-being of the individual, since PD patients show an increased risk of dementia compared to the healthy population. [79,80] With cognitive impairment beginning in the early stages of PD,  there is a corresponding need for early cognitive strategies.  Medications have some effect on Parkinson´s disease dementia, but there is no convincing evidence that the progression from mild cognitive impairment (MCI) to dementia can be delayed or prevented.