Exercise and Cognitive Training in Parkinson's Disease
Condition: Parkinson's Disease
MeSH terms: Parkinson Disease
Study type: Interventional

Summary: 
      This study compares the effects treadmill exercise, computerized cognitive training, or the
      combination of the two on executive function, dual-task performance, and performance on
      several Instrumental Activities of Daily Living (IADLs).
    

Detailed description: 
      Parkinson's Disease (PD) is recognized as both a motor and nonmotor disorder. Gait and
      mobility impairments are often associated with a decline of cognitive function, particularly
      executive function (EF), among other non-motor signs. EF is a broad category of cognitive
      functions that is generally defined as those processes necessary for purposeful,
      goal-directed behavior and supervision of ongoing cognitive processes. Deficits in EF are
      frequently seen early in PD4 and progress with time, often resulting in disruption of daily
      activities. People with PD are often impaired in real life situations in which more than one
      activity needs to be performed at a time. Dual tasking (DT) is defined as the performance of
      two different tasks simultaneously, commonly a gait plus a cognitive task. This study
      investigates the interaction of motor (gait) and non-motor (cognitive) impairments in PD.
      Studies of DT suggest that reciprocal interactions exist between gait and mental functions
      that are fundamental to the performance of daily activities. Therefore, the model of DT
      encompasses 2 major areas of PD-related impairment in a single outcome measure that is highly
      correlated with daily function.

      Performance on DT generally results in degradation of gait and/or cognitive performance. The
      investigators' pilot study in 125 people with PD has shown significant DT interference
      producing a 22% decline in gait velocity. This demonstrates deterioration of gait performance
      when subjects allocate attention to the cognitive task. Importantly, deficits on DT
      correlates with in problems in daily function, especially instrumental activities of daily
      living (IADLs), and is associated with increased risk of falling and driving impairment.
      Similarly, the investigators' pilot data in patients with moderate stage PD shows that
      deficits in DT performance are associated with poor IADL performance. Although cognitive
      deficits contribute to disability in PD, there are no treatments that effectively address
      this problem, and no studies have systematically investigated the potential benefits of
      rehabilitation strategies to improve cognitive function and related disability in this
      population.

      Emerging evidence suggests the potential of physical exercise and cognitive training to
      improve cognitive function in healthy elderly and individuals with chronic neurologic
      conditions. A Cochrane meta-analysis on the cognitive effects of aerobic exercise in older
      adults has shown that improvement of peak VO2 levels by a mean of 14% (range 5-20%) was
      associated with improvement in cognitive function, particularly EF domains including speed of
      motor processing and attention. These are the same EF domains in which deficits commonly
      occur in PD. Pilot data from the investigators' Baltimore VA study show that the
      investigators can reproduce similar gains in cardiopulmonary fitness in PD, as reported in
      the Cochrane review, with a 3-month aerobic exercise program. The investigators' group has
      also reported improvement of selected EF domains (attention and speed of processing)
      following 2 months of aerobic exercise in stroke patients12. Cognitive training is another
      potential rehabilitation modality to improve cognitive function. Recent studies in numerous
      neurological conditions and healthy older adults show that cognitive training improves
      cognition, with EF most likely to respond among all cognitive domains.

      In this project, the investigators are comparing the effectiveness of a treadmill aerobic
      exercise program (TAEX) versus a cognitive training program (TCOG) versus the combination of
      TAEX + TCOG for improving EF, DT performance and IADLs in the investigators' sample of
      Veterans and others with PD.

      The investigators' fundamental hypothesis is that 3 months of combined TAEX+TCOG will be most
      effective in improving EF, DT performance, and IADLs, compared to either regimen alone.
    

Intervention name(s): Treadmill training with aerobic exercise; Memory training with computerized memory program; Combination of treadmill training and computerized memory
Intervention type(s): Behavioral; Behavioral; Behavioral
Intervention description(s): walk on treadmill for aerobic exercise; memory testing and training on computer program; both exercise and cognitive computer training
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Treatment
Keywords: Parkinson's Disease; Treadmill Training; Exercise; Cognitive Training; Executive Function; Dual Task