Considérant ces diverses observations, l’objectif principal du présent mémoire doctoral consistera à effectuer une revue critique, systématique et quantitative des écrits scientifiques afin d’évaluer l’efficacité des programmes de stimulation cognitive, d’entraînement cognitif et de réadaptation cognitive sur les fonctions cognitives des patients atteints de la MP, avec ou sans trouble cognitif. Plus spécifiquement, ce mémoire doctoral visera à formuler des recommandations pour la recherche afin d’améliorer les futures interventions cognitives auprès de ces patients.
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CHAPITRE II : ARTICLE
The impact of cognitive interventions on cognitive symptoms in idiopathic Parkinson’s disease: a systematic review1
Marianne Couture, B.A., Ariane Giguère-Rancourt, B.A. M.Sc. & Martine Simard, Ph.D. Affiliations: Marianne, Couture, Ariane, Giguère-Rancourt & Martine, Simard : École de psychologie, Université Laval, Québec Canada and CERVO Brain Research Center,
Institut universitaire en santé mentale de Québec
Corresponding Author: Marianne Couture, 2325 rue de l’Université, École de psychologie, Université Laval, Pav. F.A., Savard, 2325 Allée des Bibliothèques, Québec
City, QC, G1V 0A6; Telephone: (418) 656-2131; Email: marianne.couture.1@ulaval.ca
1 Article published in the journal Aging, Neuropsychology, and Cognition:
Couture, M., Giguère-Rancourt, A., & Simard, M. (2018). The impact of cognitive interventions on
cognitive symptoms in idiopathic Parkinson’s disease: a systematic review. Aging, Neuropsychology, and Cognition, 1-22. https://doi.org/10.1080/13825585.2018.1513450
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Résumé
Objectif : La présente revue systématique porte sur l'efficacité des programmes
de stimulation cognitive, d'entraînement cognitif et de réadaptation cognitive sur les fonctions cognitives chez les patients atteints de la maladie de Parkinson avec ou sans trouble cognitif léger. Méthode : Les bases de données EBSCO, EMBASE, MEDLINE (OVID), PsycNET et Cochrane ont été recherchées en utilisant les termes clés suivants: Maladie de Parkinson et Trouble cognitif léger ou Trouble cognitif et Démence parkinsonienne et Réadaptation cognitive ou Entraînement cognitif ou Stimulation cognitive ou Entraînement exécutif ou Réadaptation des fonctions exécutives. Résultats
: La taille des échantillons variait de 5 à 76, mais les groupes étaient principalement
composés de moins de 30 patients. Parmi les 13 études incluses, 11 étaient des études randomisées et deux étaient des études quasi-expérimentales. En ce qui concerne les programmes d'intervention cognitive, 12 ont été considérés comme de l’entraînement cognitif, quatre comme de la stimulation cognitive et un comme une combinaison d’entraînement et de réadaptation cognitive. Les patients sans trouble cognitif ont connu des améliorations suite à de l’entraînement cognitif ou de la stimulation cognitive comparés aux contrôles actifs ou passifs telles que mesurées par 42,1% des tests cognitifs et 33,3% des questionnaires des symptômes psychologiques et fonctionnels. Les patients seulement avec trouble cognitif léger, comparés aux contrôles, se sont améliorés tels qu’évalués par 6,9% des mesures cognitives après l’entraînement cognitif. Les patients avec et sans trouble cognitif se sont améliorés, dans une certaine mesure, aux plans de la vitesse de traitement de l'information, de l'attention, de la mémoire de travail, des fonctions exécutives et surtout de la mémoire épisodique visuelle. Les patients avec trouble cognitif léger enregistrent plus d’amélioration au long cours, suite à l’entraînement cognitif au long cours que les patients sans trouble cognitif, au niveau des capacités cognitives globales, et en particulier au niveau des habiletés de planification.
Conclusion: Les résultats suggèrent une certaine efficacité des interventions cognitives
dans la maladie de Parkinson, mais des conclusions définitives ne peuvent être tirées pour le moment, car la présence de petits échantillons, le manque d'informations concernant la standardisation des interventions et une faible qualité méthodologique limitent la validité des résultats.
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Abstract
Objective: This systematic review addressed the efficacy of cognitive stimulation
(CS), cognitive training (CT) and cognitive rehabilitation (CR) to improve cognitive functions in individuals with Parkinson’s disease (PD) with (PD-MCI) and without mild cognitive impairment (PD-H). Method: EBSCO, EMBASE, MEDLINE (OVID), PsycNET and Cochrane databases were searched using the key terms: Parkinson’s Disease, Parkinson Disease and Mild Cognitive Impairment or MCI or Cognitive Impairment and Parkinson’s Disease Dementia or Parkinson Disease Dementia or Parkinson’s Dementia or Parkinson Dementia or Dementia and Cognitive Rehabilitation or Cognitive Training or Cognitive Stimulation or Executive Function Training or Executive Function Rehabilitation. Results: Sample sizes varied from 5 to 76 but most trials involved < 30 patients. Eleven studies were randomized trials and two, quasi-experimental studies. Twelve cognitive interventions were considered as CT, four as CS and one as a combination of CT with CR. PD-H benefited from CT or CS compared to active or passive controls in 42.1 % of cognitive tests, and in 33.3% of psychological and functional measures. PD-MCI alone, compared with controls, only improved in 6.9 % of cognitive measures after CT. PD-H and PD-MCI, alone or together, improved, to some extent, information processing speed, attention, working memory, executive functions, and mostly visual episodic memory. PD-MCI seem to improve better than PD-H in global cognition and planning abilities. Conclusion: The outcomes suggest some efficacy of cognitive interventions in PD, but firm conclusions cannot be drawn at this moment because small samples, lack of information regarding standardization of interventions, and poor methodological quality limit the results validity.
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Introduction
Idiopathic Parkinson's disease (PD) is the most prevalent neurodegenerative disorder after Alzheimer's disease (AD) (Aarsland, Andersen, Larsen, Lolk & Kragh Sorensen, 2003). Clinically, PD is characterized by several motor and non-motor symptoms that affect the functioning of the patient. Non-motor symptoms are common and often underestimated in PD. They include psychological and behavioral symptoms, as well as mild cognitive impairment (MCI) and dementia (PDD). MCI in PD (PD-MCI) is characterized by cognitive deficits that are intermediate between the cognitive changes associated with normal aging and the onset of dementia (Litvan et al., 2012). Prevalence of PD-MCI is approximately 27% (Litvan et al., 2011).
The cognitive profile of PD-MCI is heterogeneous; information processing speed, attentional functions, working memory, episodic memory, executive functions, visuospatial functions and language may be affected to different degrees from one patient to another (Hobson & Meara, 2015; Palavra, Naismith & Lewis, 2013). Up to 80% of MCI are likely to develop dementia later on (Calleo et al., 2012). Similarly, PD-MCI may impair the patient's ability to perform some instrumental activities of daily living (IADL), not as severely as in PDD though, and may affect quality of life (QoL) of patients and caregivers (Yarnall, Rochester & Burn, 2013).
There is no treatment to cure the disease. The objective of antiparkinsonian medication is to relieve motor symptoms of the disease, whereas nootropics can, at best, slow down cognitive decline in PDD (Litvan et al., 2012). On the other hand, presence of cognitive impairment considerably increases risk of side effects associated with antiparkinsonian medication (Jankovic & Kapadia, 2001). Therefore, it is important to explore other therapeutic approaches such as cognitive interventions that appear to be effective in improving cognition in MCI (Jean, Bergeron, Thivierge & Simard, 2010). Non- pharmacological approaches centered on cognitive symptoms can be combined with medications or can be considered as alternatives to drug therapy for patients with neurological disorders (Calleo et al., 2012).
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represent three different approaches of cognitive intervention (Clare & Woods, 2004; Huntley, Gould, Liu, Smith & Howard, 2015). CS is a non-specific approach involving development of wide range of activities such as games or small group discussions, the purpose of which is to engage and stimulate individuals (Huntley et al., 2015). This approach can be helpful for healthy elderly as well as for patients with MCI or dementia as it has been shown to significantly increase the Mini-Mental State Examination total score and total scores of other measures of global cognition (Huntley et al., 2015). On the contrary to CS, CT applies specific cognitive techniques developed in laboratory with computer or paper and pencil exercises to improve specific cognitive domains such as memory or attention. It is expected that healthy elderly and MCI participants will generalize the abilities learned in computer/paper-and-pencil exercises to their IADLs, although this is not always achieved (Jean et al., 2010; Tardif & Simard, 2011). Studies involving healthy elderly participants, patients with MCI and dementia due to Alzheimer’s disease (AD) have emphasized that the main critique common to CS and CT is lack of benefits transfer from CT to the IADL (Bahar-Fuchs, Clare & Woods, 2013; Tardif & Simard, 2011). On the contrary to CS and CT, CR is designed to specifically remediate IADL difficulties. Therefore, CR is a patient-centered intervention for people with major cognitive deficits such as patients with dementia (Bahar-Fuchs et al., 2013). As for CT, CR uses cognitive techniques developed in cognitive neuropsychology, but unlike CT, it directly applies them to learn patient realize specific IADL important for this patient (Voigt- Radloff et al., 2017). The improvement of IADL following CR is expected to increase personal satisfaction and social participation (Clare, 2017). Unlike CS and CT often administered in group format, CR is usually administered individually.
The findings regarding the effects of these three types of interventions in AD, MCI and healthy elderly individuals (Kelly et al., 2014) and AD (Huntley et al., 2015) are promising, suggesting that these interventions may also be beneficial for patients with PD and PD-MCI (Kalbe & Kessler, 2015). However, the impact of CS, CT and CR on cognition in cognitively healthy PD (PD-H) and PD-MCI patients is not clearly established yet. Nevertheless, a narrative systematic review has been conducted to assess the efficacy of certain non-pharmacological treatments, including CT, on cognition in PD-H and PD- MCI patients (Hindle, Petrelli, Clare & Kalbe, 2013). The results regarding CT showed
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benefit in information processing speed, attention, working and episodic memory, executive functions and visuospatial functions. However, this review presented some limitations. In fact, only five CT studies were included, and the efficacy of CS and CR was not verified.
More recently, a descriptive review (Glizer & McDonald, 2016) and two meta- analyzes (Lawrence, Gasson, Bucks, Toeung & Loftus, 2017; Leung et al., 2015) showed benefits of cognitive training in PD mainly on information processing speed, attention/working memory and executive functions. However, the level of cognitive functioning before the intervention was not considered in results interpretation, and studies identified CS and CR as CT or excluded CS and CR. In addition, some studies included in these meta-analysis combined CT with another treatment. It is thus difficult to isolate CT effects which highlights importance of continuing research in this domain. To date, no study has involved PDD patients; therefore, the present review will focus on PD- H and PD-MCI.
Objectives
The main objective of the present systematic review is to assess efficacy and effectiveness of CS, CT and CR programs on cognitive functions in PD patients with or without MCI. This review especially aims to critically analyze data and methodology of selected studies and to provide recommendations in order to improve future cognitive interventions in PD.
It is expected that: 1) CS, CT and CR performed in PD patients with or without MCI will have positive impact on cognitive functions of these patients; 2) CS and CT will improve cognition and subjective cognitive complaints of PD with or without MCI and 3) CR programs will improve IADLs and satisfaction with skills in PD-MCI.