Gait Training With Cognitive Tasks in Parkinson's Disease
Condition: Parkinson's Disease
MeSH terms: Parkinson Disease
Study type: Interventional

Summary: 
      Treadmill gait training combined with cognitive tasks in Parkinson's disease.
    

Detailed description: 
      This is a trial involving subjects diagnosed with Parkinson's disease, in accordance with
      guidelines established by the London Brain Bank.

      Individuals often must execute more than one task simultaneously during everyday life. When
      different activities that require attention are performed at the same time, a situation
      called Dual Task occurs.

      Under normal conditions, motor cortex areas (primary motor cortex, pre-motor cortex and
      supplementary motor area) are responsible for selecting the range of movements in a given
      action sequence, in accordance with the demands of the task and environmental restrictions,
      and after the onset of movements brought about by the motor cortex, the basal nuclei continue
      execution, leaving the motor cortex free for other tasks that require attention. However, in
      Parkinson's disease, automaticity promoted by basal nuclei is compromised and constant
      conscious control becomes necessary during gait. Thus, when an activity concurrent with this
      function is performed, the frontal regions become dedicated to the secondary task and gait is
      predominantly controlled by defective basal nuclei, which generates negative Dual Task
      interference on gait.

      Given the poor gait quality assessed in DT situations, individuals with PD have been
      instructed to avoid these circumstances. By contrast, recent evidence has demonstrated that
      gait training in conjunction with to secondary activities is capable of improving variables
      related to DT gait performance in PD.

      Considering that treadmill gait training provides greater regularity and automaticity,
      allowing subjects to divert their attention to cognitive functions, this study hypothesizes
      that DT treadmill gait training combined with cognitive tasks will promote better gait
      performance in individuals with PD.

      Patients were invited to participate in the study from phone calls. They were recruited from
      the service list in Neurology at Hospital Onofre Lopes, in Natal -Brazil. Randomization of
      individuals with respect to participation in the groups was done via the randomization.com
      website, by a person unfamiliar with the training procedures (rater 1), who assigned a color
      (yellow or green) to each group. Opaque envelopes were numbered and separated, and inside
      each envelope was a piece of paper containing the word "yellow" or "green". As a new patient
      arrived for training, rater 2 opened an envelope and was only aware of the color code of that
      particular patient. Rater 3, the lead researcher, conducted the assessment and re-assessment
      procedures. The color codes were maintained in secrecy by raters 1 and 2 throughout the
      entire study.

      Cognitive function was assessed using the Montreal Cognitive Assessment Scale (MoCA). Its
      score ranges between 0 and 30, covering aspects related to visuospatial and executive
      functions, naming, memory, attention, language, abstraction, delayed recall, as well as
      temporal and spatial orientation. Higher scores correspond to greater cognitive function.

      Disease severity was classified according to guidelines proposed by the Modified Hoehn and
      Yahr Scale, composed of seven stages, allowing categorization of both sides of the body as to
      balance and physical independence. Its scores range from 0 (no signs of the disease) to 5
      points (confined to bed or wheelchair).

      Assessment of degree of motor and functional impairment was obtained using the Unified
      Parkinson's Disease Rating Scale (UPDRS). This study used only items 2 and 3 of the scale,
      related to ADLs and motor exploration, whose scores correspond to 52 and 56, respectively.

      Kinematic assessment of overground gait was performed by the Qualisys Motion Capture Systems
      (Qualisys Medical AB, 411 13 Gothenburg, Sweden), which records the spatiotemporal variables
      of gait, as well as angular variations of hip, knee and ankle joints. This system is composed
      of eight cameras that emit and capture infrared light. The light is reflected by spherical
      passive markers positioned on bony prominences and standard body segments, in order to
      capture lower limb data. The cameras are connected to a computer, where the images collected
      are stored. Data captured in two-dimensional imaging are processed by Qualisys Track Manager
      2.6 acquisition software, which recognizes marker positioning and, based on the combination
      of images from at least two cameras connected in series, enables the generation of
      three-dimensional coordinates of movement. To that end, data are transported by 3D visual
      software (C-Motion, Rockville, MD, USA), version Basic/RT 3.99.25.8), which allows the
      reconstruction and three-dimensional analysis of the body segments marked, thereby recording
      the movements executed during gait.

      For kinematic assessment, we used 15 and 19 mm-diameter markers positioned bilaterally on the
      following structures: iliac crest, greater trochanter, medial and lateral epicondyle of the
      femur, medial and lateral malleoli, calcaneus, head of the first metatarsal and head of the
      fifth metatarsal. These markers are denominated anatomical, since their function is to
      demarcate axial joints, allowing different segments to be delimited.

      The marks that guide the trajectory of segments are classified as tracking, and are arranged
      in fours on the rectangular base (cluster). The markers were placed on the base of the
      sacrum, on the middle third of the thigh and middle third of the leg. Anatomical markers were
      fixed with double-faced adhesive tape and reinforced with surgical tape, while tracking
      markers were coupled to the body segments with elastic bands and Velcro. Markers were colored
      by the same rater on all the volunteers, in order to preserve the reliability of the marking.

      For gait training, we used an electric Gait Trainer 2 treadmill (Biodex Medical System, NY,
      USA), with a walking area measuring 160 x 51 centimeters (cm), and equipped with a bar for
      upper extremity support, heart monitoring by bioimpedance sensors located on the bar and a
      Polar Telemetry system (POLAR, USA). Coupled to the treadmill is an Unweighing System (Biodex
      Medical System, NY, USA), composed of a vertical standing frame that carries the weight
      supported by means of a harness. However, the patients did not use the weight support system
      in this study and the harness was used only as a safety precaution during the training
      sessions.

      The study procedures were performed over two days, the first for assessment and the second
      for the intervention with immediate reassessment. On the first day, the Montreal Cognitive
      Assessment (MoCA), Unified Parkinson's Disease Rating Scale and Modified Hoehn and Yahr Scale
      were applied. Next, weight and height were recorded. Finally, kinematic assessment of
      overground DT gait was carried out. On the second day, the subjects were submitted to
      treadmill training and kinematic reassessment of overground DT gait. Assessment occurred one
      day after training.

      At the onset of kinematic assessment, after marker placement and equipment calibration,
      static collection was performed to inform the system regarding body segment positioning and
      enable subsequent construction of the biomechanical model. The individual remained in the
      orthostatic position, with arms crossed over their chest, feet apart and pointing towards one
      of the cameras. Subjects were filmed for 3 seconds in this position. Next, the anatomical
      markers were removed in order to perform dynamic captures. Only tracking markers of thigh and
      leg segments remained in place, as well as those on the head of the fifth metatarsal, lateral
      malleolus and calcaneus, which correspond to the foot segment.

      At each dynamic capture, the individuals were instructed to cover a distance of 8 meters,
      walking at maximum speed, while performing a cognitive task. During each 8-meter lap a letter
      was randomly drawn and the individual was asked to say as many words as possible starting
      with that letter. When the patients unable to recall words, the subjects were also instructed
      not to stop, but rather to continue walking and trying to remember. Ten dynamic collections
      were conducted.

      On the next day, the Experimental Group (n=11) underwent treadmill gait training
      simultaneously to a protocol of cognitive tasks involving a number of attention and executive
      functions, such as verbal fluency, working memory and spatial planning. The protocol was
      created specifically for this study, based on cognitive activities proposed in previous
      studies. The training sessions lasted 20 minutes. The first three minutes allowed subjects to
      familiarize themselves with the treadmill. From the 4th minute onward, the volunteer walked
      for 1 minute while performing cognitive tasks, and in the following minute, only walked.
      Thus, the 17 remaining minutes on the treadmill alternated between one minute of treadmill
      training combined with a cognitive task and the following minute only treadmill training. The
      Control Group (n=11) underwent only treadmill training. Training lasted 20 minutes for both
      groups. Treadmill gait speed for both groups was that reported by the patient as the fastest
      possible speed while maintaining a suitable comfort level. Vital signs (heart rate and blood
      pressure) were monitored before, during and after the session.

      Immediately after treadmill training, DT overground gait was reassessed, using ten dynamics
      captures, the same procedures used on the first day.

      Kinematic data processing was conducted with Qualisys Track Manager 2.6 software (QTM), where
      markers were named and their trajectories defined. Next, the data obtained in QTM were
      exported to the Visual 3D program, where three-dimensional reconstruction of the biochemical
      model was carried out.

      Statistical analysis was conducted using the Statistical Package for the Social Sciences
      (SPSS), version 19.0. Before the analysis of each group, data distribution normality was
      verified by applying descriptive statistics procedures and the Kolmogorov-Smirnov (K-S) test.

      Measures of central tendency and dispersion were used to illustrate clinical, demographic and
      anthropometric data. For data with normal distribution, the paired t-test was used to compare
      intragroup spatiotemporal and angular variables, while the student's t-test for independent
      samples was applied to compare intergroup variables. The Mann-Whitney test was used for data
      with non-normal distribution. A significance level of 5% was set for all these tests.
    

Intervention name(s): Cognitive Tasks.
Intervention type(s): Other
Intervention description(s): The Experimental Group underwent treadmill gait training simultaneously to a protocol of cognitive tasks created specifically for this study, based on cognitive activities proposed in previous studies. The training sessions lasted 20 minutes. The first three minutes allowed subjects to familiarize themselves with the treadmill. From the 4th minute onward, the volunteer walked for 1 minute while performing cognitive tasks, and in the following minute, only walked. Thus, the 17 remaining minutes on the treadmill alternated between one minute of treadmill training combined with a cognitive task and the following minute only treadmill training. Treadmill gait speed was that reported by the patient as the fastest possible speed while maintaining a suitable comfort level.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Investigator)
Primary purpose: Treatment
Keywords: Parkinson's disease; rehabilitation; kinematics; cognition