Mild cognitive impairment, especially executive dysfunction might occur early in the course of Parkinson's disease. Cognitive training is thought to improve cognitive performance. However, transfer of improvements achieved in paper and pencil tests into daily life has been difficult. The aim of the current study was to investigate whether a multimodal cognitive rehabilitation programme including physical exercises might be more successful than cognitive training programmes without motor training. 240 PD-patients were included in the study and randomly allocated to three treatment arms, group A cognitive training, group B cognitive training and transfer training and group C cognitive training, transfer training and psychomotor and endurance training. The primary outcome measure was the ADAS-Cog. The secondary outcome measure was the SCOPA-Cog. Training was conducted for 4 weeks on a rehabilitation unit, followed by 6 months training at home. Caregivers received an education programme. The combination of cognitive training using paper and pencil and the computer, transfer training and physical training seems to have the greatest effect on cognitive function. Thus, patients of group C showed the greatest improvement on the ADAS-Cog and SCOPA-COG and were more likely to continue with the training programme after the study.
Idiopathic Parkinson’s disease (PD) is a neurodegenerative disorder characterized by loss of dopaminergic neurons and basal ganglia dysfunction. The prevalence of PD increases with age and is estimated in 100–200/100000 people [
In contrast to dementia, mild cognitive impairment (MCI) might occur early in the course of PD. Approximately, a quarter of PD-patients without dementia have mild cognitive impairment (PD-MCI). The Movement Disorder Society commissioned task force reported that MCI in PD is associated with increasing age, increasing disease duration, and disease severity [
The aim of the present study was to compare the effect of a multimodal cognitive training regime including paper and pencil tasks combined with transfer tasks and a psychomotor training with a cognitive training based on paper and pencil tasks only and a cognitive training consisting of various tasks requiring executive functions combined with transfer tasks.
240 patients, men and women who were between 50 and 80 years old and who had received a diagnosis of Parkinson’s disease according to the UK brain bank criteria [
The study was divided into two periods. Patients were enrolled into the study during an in-patient stay on a rehabilitation ward. The first part of the study (4 weeks) took place on the rehabilitation unit with a supervised cognitive training conducted by physiotherapists, occupational therapists, and two neuropsychologists.
Patients were randomly allocated to one of the three training groups. Randomisation was conducted by using a computer-generated sequence. All groups received a cognitive training regime using paper and pencil material and a multimedial PC training. Group A received cognitive training only, while group B took part in a transfer training and a cognitive training. Group C conducted a cognitive training, and transfer and psychomotor trainings. Patients of group A and B had additional relaxation training and occupational training without transfer training to compensate for the additional training time of group C.
After randomisation medical history was taken, patients underwent medical and neurological assessments and were asked about their cognitive difficulties. They identified cognitive deficits that they want to improve. Severity of Parkinson’s disease was assessed by using the Unified Parkinson’s Disease Rating Scale (UPDRS) [
Demographic data included information about age, body mass index (BMI), duration of disease, weekly sports activity, smoking habits, medication and concomitant diseases (hypertension, chronic obstructive pulmonary disease, thyroid disease, diabetes mellitus, hypercholesterinaemia, and osteoarthritis), education, profession, family, onset and severity of disease, history of psychosis, and impairments in daily living. Patients kept an activity log one week prior to the training programme and one week prior to the third assessment. Sports activities, time spent sitting, and doing light, moderate, and heavy work were recorded. The ethical committee of the Justus-Liebig University has approved the study and all patients have given written informed consent. Figure
Study design group A: Cognitive training; group B: Cognitive + transfer training, group C: Cognitive, transfer + motor training.
For the assessment of the longitudinal course of the disease, the Unified Parkinson`s disease rating scale (UPDRS) was applied [
For the assessment of the goals of the cognitive training, the Goal Attainment Scale was chosen. The Goal Attainment Scaling (GAS) was used to define individual realistic and feasible goals according to patients’ needs and expectations. The cognitive difficulties of the patients were assessed and the results of the baseline test were explained to the patients. In this study, GAS was measured using a 6-point Likert scale −3 represented function that is worse than at the start of treatment, −2 no change, −1 some improvement without meeting the expected goal, 0 represented goal achievement and +1 or +2 overachievement (exceeding the defined therapeutic goal) [
At the beginning of the study, all patients underwent two cognitive screening tests (PANDA and MMSE) [
Although the ADAS-COG is the primary outcome measure in many clinical trials [
The conceptual framework underlying the ADAS-COG is to identify three reproducible factors: memory, language, and praxis [
The SCOPA-COG is an instrument which was designed to assess the specific cognitive deficits found in Parkinson’s disease [
Since PD-patients show pronounced deficits in executive functions additional tests for evaluation of executive functions were conducted at baseline, second and final assessment: Information processing speed (Paced auditory serial addition test (PASAT) [
For assessment of health-related quality of life, patients filled in the PDQ-39 [
The assessments were performed by psychologists and movement disorders specialists who were blinded to the treatment allocation of the patients.
Patients performed the training programmes in onstage and after optimisation of the medication. Dopaminergic deficits may affect the performance of patients in cognitive and physical exercises [
The cognitive training programme was individually tailored to patients’ requirements based on the results of the baseline tests. Four individual (one-to-one) 60 min-lessons took place each week. All patients received at least 14 cognitive training sessions.
The training included training of attention, concentration, biographical work, reasoning, memory, working memory, social rules, anticipation, cognitive information speed, prospective memory, cognitive estimation, problem solving, sequencing and planning, associations, and coping with disease.
For the training programme, a set of tasks requiring executive and memory functions was chosen from a variety of specific tests. Executive tasks of the BADS, which were not used for the baseline assessment, were included in the training. Simple patterns of the “Raven’s Progressive Matrices” were used to establish problem solving strategies in the patients. Picture arrangement tasks, picture completion tasks, block design, and object assembly were adapted from the “Wechsler Intelligence test for children.” For improvement of verbal fluency, patients were encouraged to tell short stories or discuss short text passages. Photos were used for training of working memory. Tasks including visual search and rule finding were practised by using a PC-based programme. The training methods were designed to improve the various cognitive deficits, diagnosed at baseline, and focused on the executive functions. Task difficulty was adapted to the individual performance level of the patients. Table
Cognitive training.
Training section | Examples for tasks |
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Planning strategies | Shopping lists, key search of the BADS subscales, to get items out of a bottle, special wooden 3-dimensional jig saw |
Mnemonics | Using memory hooks, writing of suitable mnemonics, and planning where to place them |
Decision making | Computer tasks, painting |
Set shifting | To solve various tasks according to changing rules, to calculate for 5 min, then to read for 10 min and to write for 5 min, or to switch tasks after every third answer, categorising items according to different rules |
Calculation | Calculation tasks |
Navigational skills | Finding the way through a maze on a screen, finding the way around obstacles on a paper or on a screen |
Information speed processing | Connecting numbers or letters, connecting figures to an image, and finding the meaning of a fictive word |
Summary | Extracting the relevant information from news or from a story or a short movie |
Concentration | Finding similar or dissimilar items |
The aim of the training was to support patients to manage their daily life better and to become more self-confident. Therefore, patients were asked to practise competence in tasks of daily routines. The transfer training programme was composed according to the baseline test results. Special preferences of the patients were considered. The transfer training included training of concentration, use of mnemonics, strategy (planning), navigational skills, impulse control, decision processes, listening training and memory, behaviour, calculating, handling of money, summarising of articles read or heard, and decision making. Typical tasks were to find the way to the supermarket or to prepare a meal, to go to the bank, pay a bill, and to use mnemonics. Patients had to look after a vegetable patch and some flowers to improve prospective memory. For better evaluation of the training, tasks were allocated to different categories: concentration, strategy, orientation, planning, and the use of mnemonic devices. The training took place 3 times a week, each lasted 90 min. Patients received at least 10 sessions of transfer training (Table
Transfer training.
Tasks | Examples |
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Planning and sequencing | Preparing of meals, shopping, construction of items, repairing of items, and art works |
Reasoning | Finding the right solution, using deductive strategies, finding a way by incomplete instructions, to find out how things work, and use of unfamiliar tools |
Concentration | Sorting and selection tasks, to fit small items, to build a model of a castle, knitting and weaving patterns, jig saw, to listen to a story and to press a button, when a previously identified word was read |
Memory | Role play, music performance, singing, and learning poems |
Working memory | Games, n-back tasks, dual tasks like driving on a driving simulator and listening to the news, calculating during walking, to follow complex instructions, and to extract the necessary information out of a long text |
Anticipation | Walking on a crowded sidewalk, watching a movie and predict what people will do next, finish a picture story, and decipher the mood of people on pictures |
Pospective memory | To look after a vegetable patch and flowers, to keep appointments, and to take over special tasks at the beginning of the week |
Cognitive information speed | Follow verbal instructions given with increasing content of information and speed, card games, and complex reaction tasks |
Social rules | Define the appropriate behaviour in different situations, role play, |
Association | Solving tasks by association, finding common features, and categorisation |
Cognitive estimation | Estimation of height, quantity of items shown, and weight |
Group C performed a motor training resembling motor skill training or psychomotor training applied in children. The training included games and tasks designed to enhance inhibitory control, working memory, attention, visuospatial abilities, and planning and motor skills [
A long lasting training effect depends on continuing training. Thus, cognitive training and exercises need to be adapted to the home environment. Accordingly, the caregivers most often the patients’ family were included into the programme. The education for the caregivers consisted of 5 modules: information about Parkinson’s disease, psychological aspects and the role of a caregiver, information about help aids, information on care management, assessment of individual problems, support in cognitive (all groups) and transfer training (groups A and B), NW and movement skill training. Course instructors were a specialist nurse, a physiotherapist and a psychologist.
Corresponding to the allocation to the training groups patients got written instructions for the cognitive training, transfer training, and physical exercises at home. The instructions encompassed a collection of the tasks conducted during the stay at the hospital. Caregivers were advised how to organise the training but the hospital staff did not organise the training at home. All patients were asked to perform three 45 min cognitive training sessions per week using paper, pencil, and a computer programme. Patients of groups B and C were asked to continue with two transfer trainings per week and patients of group C got instructions to conduct movement skill training and aerobic training lessons twice a week. To compensate for the additional physical training of group C, patients of group A and B were provided with prescriptions for relaxation training.
All patients were tested using a neuropsychological test battery at three time points: prior to the training, and prior to discharge to assess the short-term effect, and 6 months after the training to assess the long-term effect.
Caregivers were asked regarding their own well being and regarding the cognitive competence of the patients in activities of daily living. Patients and caregivers kept a diary to record training lesions. The diaries were collected and analysed at the 3rd assessment.
Statistical analysis was conducted using IBM SPSS Statistics 18.0 (IBM, Somers, USA) statistical software. Formal power analysis was performed prior to the study. The power analysis was based on an improvement of the ADAS-COG by 3 points. The results indicated that a sample size of 60 subjects per group was sufficient. Since comprehensive training programmes including several assessments imply dropouts, a drop-out rate of 20% was taken into account. Demographic data on ordinal level were analysed by using a nonparametric test (Kruskall-Wallis). The Kruskall-Wallis test was also applied for the analysis of depression and the BADS subscales. Demographic continuous data were analysed by using One-way ANOVA. Linear model for repeated measures was used for analysis of training outcomes. The repeated measure analysis provides information about “between and within subjects” effects. Within subject effects give information about training effects over the assessment period. Linear trends showed if there was a systematic change of training effects over time. The interaction between groups and the linear trend of days (assessments) provided information about the difference in the rate of improvement between groups. The between subject factor compared the overall treatment effect between the groups. Post hoc analysis was done using Bonferroni tests. Parametric data were tested for normal distribution by using the Kolmogorov-Smirnov test. Significance level was set at 0.05.
In total 223 patients (97.1%) completed the programme during the in-patient stay in the hospital: 71 (90%) patients in group A, 75 (93.8%) in group B, and 76 (95%) patients in group C. The patients were on average 64 ± 4 years old and that 8 years diagnosed with PD. The patients did not differ significantly in demographic data (Table
Demographic data.
Group A | Group B | Group C | |||||||
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Gender | F = 35 | M = 36 | F = 36 | M = 39 | F = 36 | M = 40 | |||
Duration of PD (months) |
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Stage (Hoehn and Yahr) | |||||||||
II |
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III |
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IV |
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Medication | |||||||||
L-Dopa | Yes: |
Yes: |
Yes: |
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Dopamine agonist | Yes: |
Yes: |
Yes: |
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MA0 inhibitor |
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COMT inhibitor |
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Antidepressants |
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Neuroleptic drugs |
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Formal education (years) |
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Marital status m = married, s = single, and p = partner | m = 58 | s = 9 | p = 5 | m = 61 | s = 11 | p = 3 | m = 63 | s = 9 | p = 4 |
Home (own home, renting) | Own: |
Renting: |
Own: |
Renting; |
Own: |
Renting: |
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BMI |
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Smoking | Yes: |
No: |
Yes: |
No: |
Yes: |
No: |
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Sports activities (min)/week |
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Physical work h/week |
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Very hard |
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Hard |
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Comorbidity | |||||||||
Coronary heart disease |
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Hypertension |
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Diabetes mellitus |
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COPD |
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Thyroid disease |
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Hypercholesterinaemia |
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Osteoarthritis |
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Number of patients is shown as total number, mean values are shown
Table
Distribution of cognitive training.
Training section | Percentage of time spent (%) |
---|---|
Planning strategies | 17 |
Mnemonics | 15 |
Decision making | 15 |
Set shifting | 15 |
Calculation | 10 |
Navigational skills | 10 |
Information speed processing | 8 |
Summary | 5 |
Concentration | 5 |
Patients of group B conducted 11.2 ± 0.5 and patients of group C 11.4 ± 0.6 transfer training sessions (
Table
Transfer training: time spent on different tasks.
Tasks | Percentage of time spent (%) |
---|---|
Planning and sequencing | 18 |
Reasoning | 11 |
Concentration | 11 |
Memory | 10 |
Working memory | 8 |
Anticipation | 8 |
Prospective memory | 7 |
Cognitive information speed | 7 |
Social rules | 5 |
Association | 5 |
Cognitive estimation | 4 |
Patients had many difficulties to cope with the tasks. They struggled to find strategies to solve the tasks on their own, for example, they had difficulties to find the correct path through the parcours with obstacles and to follow the changing rules (set shifting). Patients tended to perseverate. Walking through a room with eyes closed only guided by different touches of the therapist challenged the patients as well since PD-patients have both deficits in proprioception and in perception of stimuli. The type of tasks and exercises were new to the majority of patients. PD-patients needed more time and repeated instructions to learn mental imagery. The lessons were conducted as individual lessons. It was not possible to conduct group lessons. About 40% of the training took place outdoors, 60% in the gym.
The caregivers’ knowledge about Parkinson’s disease was assessed with a questionnaire at the end of the training programme. They were able to answer on average 27 ± 2.1 questions out of 30 compared to 20.2 ± 4.5 questions prior to the education programme. The carers’ burden scale did not reveal any significant differences compared to baseline assessment. However, the questionnaire showed low burden in 60% of carers of group A, in 58% of group B, and in 62% of group C. Moderate burden was revealed in 30% of carers in group A, in 33% in group B, and 32% in group C. However, caregivers reported in a semi structured interview at the end of the education programme that they felt more confident. There was no difference between the caregivers of group A, B, and C.
60% of patients of group A continued practising cognitive tasks 3 times a week for 45 min, while 40% conducted the training only once or twice per week. All patients of group B tried to continue the transfer tasks learnt during the rehabilitation, but further assessment showed that only 60% performed transfer tasks following a regular schedule. 75% of the patients of group B practised cognitive tasks 3 times a week. 90% of patients of group C pursued the training at home with the same quantity and intensity. They conducted a motor training three times a week, most often accompanied by their partners. The partners of patients of groups B and C managed to support their patients in practising transfer tasks. They asked them to prepare meals, to write the shopping list, or to go to the bank.
The screening tests for cognitive functions did not reveal any differences between the groups and the results did exclude dementia. The neuropsychological baseline assessment did not reveal any differences between the groups either. Patients of all three groups had shown deficits mainly in tests addressing executive functions. Consecutively, the performance of the patients was worse on the subtests of the SCOPA-COG, semantic fluency, LURIA, dice and assembly pattern, zoo test of the BADS and PASAT. The memory tasks such as immediate and delayed recall were only mildly disturbed.
The multiple-choice word test (MWT-B) was conducted as a measure for premorbid intelligence; the groups did not differ significantly either (
Summary of neuropsychological test results.
Test | Baseline | T1 | T2 | Significant differences between the groups |
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ADAS-Cog |
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Group A |
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Group B |
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Group C |
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SCOPA-Cog | ||||
Group A |
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Group B |
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Group C |
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BADS Zoo (profile) |
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Group A |
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T1: Chi-square: 49.31; |
Group B |
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Group C |
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BADS instruction |
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Group A |
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T1: Chi-square: 7.1; |
Group B |
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Group C |
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BADS 6 elements |
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Group A |
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T1: Chi-square: 39.4; |
Group B |
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Group C |
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PASAT |
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Group A |
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Group B |
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Group C |
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All groups improved on the ADAS-COG significantly shown by a significant linear trend (
In accordance the SCOPA-COG test showed a significant difference between the groups (Figure
Group C improved significantly more on the SCOPA-COG test than group A and B.
The BADS-subscales especially the zoo map are a very demanding task requiring excellent planning skills. The subtests of the BADS (rule shift cards, zoo map, modified 6 elements test) showed the following results.
The baseline scores of the rule shift cards did not differ between the groups. There was a mild but significant difference between the groups at the second assessment (Chi-square = 7.1;
At baseline assessment group C showed a tendency to perform better on the BADS zoo test. The mean profile scores of all groups were higher at the second assessment, but significant more patients of group C improved compared to groups A and B. There was a clear group difference at the second (Chi-square = 49.31;
There was no difference in the performance in the 6 elements test at baseline assessment. Group C showed a greater increase of the average profile scores leading to significant group differences at the second (Chi-square = 39.3;
The results of the PASAT test did not differ between the groups at baseline assessment, all groups produced on average 50% correct answers. Group A improved only marginally. Groups B and C benefitted from the training programme shown in a significant linear trend for assessments (
Only 157 patients (group A: 50, group B: 53, and group C: 54) managed the PASAT test on the first assessment and were included in the statistical model. The other patients did not succeed in finding a strategy to cope with the task. On the second and third assessment 56 patients of group A, 64 patients of group B, and 71 patients of group C scored on the test. Groups B and C showed further improvement between the second and final assessment.
The goals were identified at the baseline assessment. On the final assessment it was reviewed whether the goals were obtained. Patients of group C reached more often the main goal than the other groups (Chi-square: 57.1;
Individual goals chosen by the patients and percentage of goal achievement.
Groups | Goal | Goals chosen | Goals obtained | Significance | ||
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Total number | Percentage (%) | Total number | Percentage (%) | |||
A |
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21.1 |
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20 | ||
B |
Dual tasking |
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18.7 |
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64 |
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C |
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20 |
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67 | ||
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A |
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21.2 |
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20 | ||
B |
Planning of complex tasks |
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21.3 |
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56.3 |
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C |
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22.4 |
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58.9 | ||
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A |
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14.1 |
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40 | ||
B |
Decision making |
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14.7 |
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54.5 |
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C |
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18.4 |
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71.4 | ||
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A |
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18.3 |
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30.8 | ||
B |
Rule recognition and rule shifting |
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21.3 |
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43.8 |
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C |
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18.4 |
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71.4 | ||
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A |
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16.9 |
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25 | ||
B |
Delayed recall |
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16 |
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58.3 |
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C |
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14.5 |
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82 | ||
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A |
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8.5 |
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67 | ||
B |
Search strategies |
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8 |
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83.3 |
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C |
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6.6 |
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80 |
Effect of the training programme on the main goals (GAS).
GAS |
Group A |
Group B |
Group C |
Total | ||||
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Total | Percent | Total | Percent | Total | Percent | Total | Percent | |
−3 |
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16.7 |
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8 |
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2.6 |
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8.9 |
−2 |
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13.8 |
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6.7 |
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3.9 |
|
23.7 |
−1 |
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40.3 |
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28 |
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23.6 |
|
30 |
0 |
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18.1 |
|
25.3 |
|
30.2 |
|
24.7 |
1 |
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11.1 |
|
32 |
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26.3 |
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25.1 |
2 |
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0 |
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0 |
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7.9 |
|
2.7 |
71 | 75 | 76 | 223 |
−3 = worse than start of treatment, −2 = no change, −1 = some improvement, 0 = goal achievement, +1 = slight over-achievement, +2 = great over-achievement.
The patients had selected the goals based on their self-evaluation of their cognitive impairment and on the advice given by the psychologist after the baseline testing. The main cognitive impairments reported by the patients could be attributed to the following domains: dual tasking, planning of complex and sequential tasks, decision making, rule recognition, rule shifting problems, delayed recall, and difficulties in finding misplaced items.
Table
Planning of complex tasks, rule recognition, and shifting and dual tasking were identified as goals most often. While there was no significant difference between the goals chosen by the three groups there was a significant difference between the percentages of patients obtaining the goals between the groups. 71% of patient obtained the goal “decision making,” but only 40% of patients of group A.
Table
More patients of group A compared to group B and C did not obtain the chosen goal or deteriorated compared to baseline, while 27.6% of patients of group C obtained the goal and 39.4% exceeded the expectations mildly and 7.6% substantially. The difference between the groups was significant (Chi-square = 48.23;
15% of the patients in group A, 20% of group B, and 18% of patients of group C reported to suffer from depression and received medication. The results on the HADS depression scale indicated in 20% of patients of group A and group C, respectively, and in 25% of patients of Group B the presence of a mild to moderate depression. The anxiety level was assessed by using the Hamilton Anxiety Scale and did not differ between the groups.
The results of the PDQ-39 at the final assessment showed that patients of group C rated their health-related quality of life higher than the other groups. 13.8% of patients of group A, 38% of patients of group B, and 52% of patients of group C reported less impairment due to PD (Figure
PD-patients of group C reported less PD-specific impairment at the final assessment. The
The UPDRS score showed a mild improvement in all groups at the final assessment but there were no significant differences between the groups indicating that the cognitive improvement could not be referred to a nonspecific effect resulting from general physical improvement (Table
UPDRS.
Group A |
Group B |
Group C |
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Baseline | |||
UPDRS Motor scale |
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UPDRS Sum Score |
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Final assessment | |||
UPDRS Motor scale |
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UPDRS Sum Score |
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The patients of group C reported that they had adapted a more active life style, felt more confident in activities of daily living, and had taken over some more chores. They perceived their partners and caregivers as being helpful. They enjoyed the participation of their partners in conjoint sports activities.
Patients of group B also regarded the training programme as helpful but reported of having still problems with activities of daily living. Patients of group A had more difficulties with transfer of skills into daily life and the carryover effect was smaller than in the other groups.
65% of the caregivers of patients in group C, 54% of caregivers of group B, and 49% of caregivers of group A found that competence and cognition of their patients had improved in activities of daily living. A deterioration of the performance in daily living was reported in 11% of group C, 17% of group B, and 25% of group A.
Caregivers felt more relaxed and competent to manage difficult situations, while patients accepted the guidance of their caregivers better than prior to the training. Caregivers felt confident to support the partners with the training at home.
Patients of group A felt that the cognitive training was arduous at times. Some patients perceived the training as stressful. Patients of groups B and C were asked to compare the training programmes. Patients of group C preferred the motor training to transfer training and cognitive pencil and paper tasks. 80% of patients judged the training as strenuous and felt sometimes exhausted. 30% of patients reported of being frustrated at times but did not ask for help or further explanations.
In summary patients who conducted a multimodal cognitive rehabilitation programme improved most on the ADAS-COG and SCOPA-COG, reported a better quality of life, were more active, and continued coping with daily tasks. Patients of group C were physically more active after the training programme and a higher percentage of patients of group C continued with the cognitive training. Physical improvement did not explain the difference in cognitive performance after the end of the study.
Dementia is a part of the Parkinson’s disease spectrum. Currently, there is no treatment aimed at halting or reversing disease progression [
Oswald et al. [
The groups managed the executive tests very differently. The BADS zoo map is a very challenging test as mentioned above and requires various training approaches to achieve an improvement. Only patients of group C obtained a permanent improvement on this test.
Thus, the different training schedules affect the training outcome also regarding the type of tasks, which were better performed. Patients of group C managed executive tasks better than group A and B, which is shown by the better performance on the BADS test battery and the better results on the SCOPA-COG. Exercise and endurance training is thought to improve executive functions most. Furthermore, brain areas which are more vulnerable for age-related volume lose benefit most from physical exercise.
Patients with mild cognitive impairment benefit more from cognitive training than more advanced patients. Studies have shown that the effect of physical exercise on demented patients is limited. Patients have to be capable of understanding the training programme. Depression might also influence the performance in neuropsychological tests. Klepac et al. [
The findings of the study confirmed as well that PD-patients benefit from a specific cognitive training. Based on the results of a previous study [
In contrast to a study by París et al. [
Sinforiani et al. [
Quality of life is closely associated with nonmotor symptoms of PD, especially cognitive function [
Research over the last decade has shown that cognitive deficits affect motor performance. Patients with cognitive deficits had more difficulties in motor tests than patients without cognitive deficits. Hausdorff et al. [
One might criticise that we compared three different treatment arms and did not include a control group without cognitive training in this study. However, patients were enrolled into the study during their stay on a rehabilitation unit and complained of a deterioration of their cognitive performance. For this reason, it was not possible to withhold treatment. Further, we had shown the superiority of a cognitive training compared to standard treatment in a previous study [
Another limitation is that there are no evidence-based data for the transfer training. Further research is necessary to evaluate and validate which transfer exercises are useful tools. The psychomotor training or movement skill training has been used for many years in children and has been applied in patients with dementia [
One might also argue which improvement on the ADAS-COG or SCOPA-COG might be clinically relevant. However, the scales are validated and had been often applied in clinical trials. The clinical relevance of the improvements has also been shown by the observed translation into real life. Furthermore, due to the short follow-up period of 6 months we cannot report on long-term effects. However, studies assessing long-term results are very difficult to conduct since it is very difficult to keep the medication stable.
To our knowledge, the results of the current study show for the first time, that a multimodal cognitive training in patients with Parkinson’s disease can lead to improvements of cognitive function and improves quality of life. In addition, there was some translation of the cognitive improvement into real life. We also want to emphasize that it was a blinded randomised study and the drop-out rate was low.
In conclusion, we have shown that PD-patients with cognitive deficits benefit from a multimodal cognitive training. The multimodal training was superior to a paper- and pencil-based cognitive training. The combination of the cognitive training with a motor training seems to be most successful and the short-term effect of the training on cognitve functions was comparable to the effect found in the rivastigmine trial. However, we cannot predict the long-term effect of the cognitive multimodal training. The study has shown some translation of cognitive improvements into “real” life. Admittedly, the multimodal training of cognitive functions is time consuming, requires high motivation of the patients, and put demands on resources. Due to the quantity and quality of the trainings sessions it will also be costly. On the other hand dementia is a risk factor for falls, high morbidity and transfer to nursing homes, which increases the costs for the patients’ care substantially and jeopardizes the patients’ quality of life.
The authors would like to thank Dr. Werner Jackstädt-Stiftung for the generous support of the study.