The effects of cognitive reserve and lifestyle on cognition and dementia in Parkinson's disease-a longitudinal cohort study

OBJECTIVE: Cognitive reserve theory seeks to explain the observed mismatch between the degree of brain pathology and clinical manifestations. Early-life education, midlife social and occupational activities and later-life cognitive and social interactions are associated with a more favourable cognitive trajectory in older people. Previous studies of Parkinson's disease (PD) have suggested a possible role for the effects of cognitive reserve, but further research into different proxies for cognitive reserve and longitudinal studies is required. This study examined the effects of cognitive lifestyle on cross-sectional and longitudinal measures of cognition and dementia severity in people with PD. METHODS: Baseline assessments of cognition, and of clinical, social and demographic information, were completed by 525 participants with PD. Cognitive assessments were completed by 323 participants at 4-year follow-up. Cognition was assessed using the measures of global cognition dementia severity. Cross-sectional and longitudinal serial analyses of covariance for cognition and binomial regression for dementia were performed. RESULTS: Higher educational level, socio-economic status and recent social engagement were associated with better cross-sectional global cognition. In those with normal cognition at baseline, higher educational level was associated with better global cognition after 4 years. Increasing age and low levels of a measure of recent social engagement were associated with an increased risk of dementia. CONCLUSIONS: Higher cognitive reserve has a beneficial effect on performance on cognitive tests and a limited effect on cognitive decline and dementia risk in PD

Contribution of brain or biological reserve and cognitive or neural reserve to outcome after TBI: a meta-analysis (prior to 2015)

Brain/biological (BR) and cognitive/neural reserve (CR) have increasingly been used to explain some of the variability that occurs as a consequence of normal ageing and neurological injuries or disease. However, research evaluating the impact of reserve on outcomes after adult traumatic brain injury (TBI) has yet to be quantitatively reviewed. This meta-analysis consolidated data from 90 studies (published prior to 2015) that either examined the relationship between measures of BR (genetics, age, sex) or CR (education, premorbid IQ) and outcomes after TBI or compared the outcomes of groups with high and low reserve. The evidence for genetic sources of reserve was limited and often contrary to prediction. APOE ∈4 status has been studied most, but did not have a consistent or sizeable impact on outcomes. The majority of studies found that younger age was associated with better outcomes, however most failed to adjust for normal age-related changes in cognitive performance that are independent of a TBI. This finding was reversed (older adults had better outcomes) in the small number of studies that provided age-adjusted scores; although it remains unclear whether differences in the cause and severity of injuries that are sustained by younger and older adults contributed to this finding. Despite being more likely to sustain a TBI, males have comparable outcomes to females. Overall, as is the case in the general population, higher levels of education and pre-morbid IQ are both associated with better outcomes.Jane L. Mathias, Patricia Wheato

Patterns of cognitive dysfunction in multiple sclerosis

Multiple sclerosis (MS) is one of the most frequent diseases of the central nervous system in young adults. MS believed to be autoimmune and manifests itself mostly as white matter demyelination and associated damage of axons. Various symptoms occur in MS. Cognitive dysfunction is a common symptom occurring in 30-70% of patients at all stages of the disease. The purpose of this study was to investigate the pattern of cognitive dysfunction in different MS subtypes and clinically isolated syndromes suggestive of MS relative to control participants in the Greek population. We suppose that distinct patterns of cognitive dysfunction might occur. We suggest a cognitive science approach of cognitive dysfunction in MS based on impairments on working memory and executive functions. Relapsing remitting patients (RR N=130), secondary progressive patients (SP N=30), primary progressive patients (PP N=30), patients with clinically isolated syndrome (CIS N=42) and healthy control participants (N=60) were assessed by the Brief Repeatable Battery of Neuropsychological Tests and a version of the Stroop Word Color Interference Test. The Principal Component Analysis (PCA) on our battery of tests yielded three components for our sample and we defined the corresponding cognitive types the dysexecutive type (C1), the amnestic type (C3), the working memory dysfunction type (C2) and combinations of them. The distribution of the frequencies of appearance of each cognitive type to each clinical subtype suggests a relatively homogeneous pattern of cognitive dysfunction in MS. The dominant cognitive type is the working memory dysfunction type (13.0%). The multivariate analyses of covariance showed that all MS patients performed significantly poorer from control participants in C1 and C2 component scores. However, patients with CIS and RR MS had higher scores than patients with PP and SP MS in C1 component (executive functions) and the significance remained even after controlling for physical disability. Concerning the C3 component scores (verbal memory) only RR MS had significantly lower scores relative to controls. The present battery of tests is sensitive in detecting cognitive dysfunction in MS even in the early stages of the disease and in patients with CIS. Moreover, we suggest three distinct profiles of cognitive dysfunction which could be useful in order to suggest domain specific cognitive interventions.Η Σκλήρυνση Κατά Πλάκας (ΣΚΠ) είναι μια από τις συχνότερες νόσους του κεντρικού νευρικού συστήματος σε νεαρούς ενήλικες και εκδηλώνεται κυρίως ως απομυελίνωση που συνοδεύεται από αξονικές βλάβες και χαρακτηρίζεται από ποικιλομορφία συμπτωμάτων. Ένα από τα πιο συχνά συμπτώματα είναι η γνωστική δυσλειτουργία σε ποσοστό 30 70% των ασθενών. Ο βασικός στόχος αυτής της μελέτης είναι η διευκρίνηση της ΣΚΠ τύπου γνωστικής δυσλειτουργίας και των ενδεχόμενων διαφορετικών προτύπων σε ασθενείς διαφορετικών τύπων ΣΚΠ. Προτείνουμε μια επεξηγηματική προσέγγιση η οποία να βασίζεται σε ελλείμματα στη μνήμη εργασίας και στις επιτελικές λειτουργίες ευρύτερα. Η Σύντομη Επαναλαμβανόμενη Συστοιχία Νευροψυχολογικών Δοκιμασιών και μια εκδοχή της Δοκιμασίας παρεμβολής λέξης χρώματος του Stroop χορηγήθηκαν σε 130 ασθενείς με διαλείπουσα μορφή ΣΚΠ (ΕΥ), 30 ασθενείς με δευτεροπαθώς προϊούσα μορφή (ΔΠ), 30 ασθενείς με πρωτοπαθώς προϊούσα μορφή, 42 ασθενείς με κλινικά μεμονωμένο σύνδρομο (ΜΣ) και 60 υγιείς μάρτυρες. Από το μοντέλο ανάλυσης κυρίων συνιστωσών των δοκιμασιών εξάγονται 3 ανεξάρτητες συνιστώσες στο δείγμα μας και οι γνωστικοί τύποι ορίστηκαν σε σχέση με αυτές ως ο δυσεπιτελικός τύπος δυσλειτουργίας (C1), ο αμνησικός τύπος (C3), ο τύπος δυσλειτουργίας της μνήμης εργασίας (C2) και οι συνδυασμοί αυτών. Η κατανομή των συχνοτήτων σε κάθε κλινικό τύπο της νόσου πρότεινε ένα σχετικά ομοιογενές πρότυπο γνωστικής δυσλειτουργίας στη ΣΚΠ. Ο επικρατέστερος τύπος μπορεί να θεωρηθεί ο τύπος δυσλειτουργίας της μνήμης εργασίας (13.0%). Η πολυμεταβλητή ανάλυση συνδιακύμανσης ανέδειξε ότι όλοι οι ασθενείς παρουσίαζαν σημαντικά χαμηλότερες επιδόσεις από τους μάρτυρες στις συνιστώσες C1 και C2. Καλύτερες ήταν και οι επιδόσεις των ασθενών με ΜΣ και ΕΥ σε σχέση με τους ασθενείς με ΠΠ και ΔΠ στη συνιστώσα C1 (επιτελικές λειτουργίες) και η σημαντικότητα παρέμενε ακόμα και μετά τον έλεγχο της φυσικής αναπηρίας. Οι βαθμοί στη C3 συνιστώσα της λεκτικής μνήμης ήταν σημαντικά χαμηλότεροι από τους μάρτυρες μόνο για τους ασθενείς με ΕΥ. Η συστοιχία δοκιμασιών της παρούσας μελέτης είναι ευαίσθητη στην ανίχνευση γνωστικών ελλειμμάτων ήδη από τα πρώτα στάδια της νόσου και τους ασθενείς με κλινικά μεμονωμένο σύνδρομο και προτείνει ένα σχετικά ομοιογενές μοντέλο δυσλειτουργίας στη ΣΚΠ για όλους τους τύπους της νόσου. Επιπρόσθετα διακρίνει τους ασθενείς με ΣΚΠ σε τρία διαφορετικά πρότυπα γνωστικής δυσλειτουργίας τα οποία μπορεί να χρησιμεύσουν για την πρόταση εξειδικευμένων γνωστικών παρεμβάσεων

An APOA1 promoter polymorphism is associated with cognitive performance in patients with multiple sclerosis

Background: Elevated ApoA1 levels have been associated with decreased dementia risk. The A-allele of the APOA1 -75G/A promoter polymorphism has been associated with elevated ApoA1 levels. Objective: We sought to investigate the effect of the APOA1 -75G/A promoter polymorphism on cognitive performance in patients with multiple sclerosis (MS). Methods: A total of 138 patients with MS and 43 controls were studied and underwent neuropsychological assessment with Rao's Brief Repeatable Battery and the Stroop test. All patients were genotyped for APOA1. Results: APOA1 A-allele carriers displayed superior overall cognitive performance compared with non-carriers (P 0.008) and had a three-fold decrease in the relative risk of overall cognitive impairment (OR 0.29, 95% CI 0.11-0.74). Regarding performance on individual cognitive domains, although APOA1 A-allele carriers performed better than non-carriers on all tests, this was significant only for semantic verbal fluency and the Stroop interference task (P 0.036 and 0.018, respectively). Conclusions: We found an association of the APOA1 -75G/Apromoter polymorphism with cognitive performance in MS. This effect was most prominent on semantic verbal fluency and the Stroop interference task. © SAGE Publications 2009

APOE epsilon 4 is associated with impaired verbal learning in patients with MS

Objective: To investigate the effect of APOE epsilon 4 on different cognitive domains in a population of Greek patients with multiple sclerosis (MS). Methods: A total of 125 patients with MS and 43 controls were included in this study and underwent neuropsychological assessment with Rao’s Brief Repeatable Battery. All patients with MS were genotyped for APOE. The effect of APOE epsilon 4 on different cognitive domains was investigated. Results: Fifty-one percent of patients with MS were cognitively impaired. epsilon 4 carriers had a sixfold increase in the relative risk of impairment in verbal learning vs noncarriers (OR 6.28, 95% CI 1.74 to 22.69). This effect was domain-specific and was not observed in other cognitive domains assessed by the battery. Conclusion: We found an association of APOE epsilon 4 with impaired verbal learning in patients with multiple sclerosis

Cognitive impairment in different MS subtypes and clinically isolated syndromes

Objective: To investigate the pattern of cognitive impairment in patients with relapsing-remitting (RR), secondary progressive (SP), primary progressive (PP) multiple sclerosis, and patients with clinically isolated syndrome (CIS) suggestive of MS, relative to control participants in the Greek population. Methods: RR patients (N=75), SP patients (N=29), PP patients (N=23), CIS patients (N=33), and healthy control participants (N=43) were assessed by the Brief Repeatable Battery of Neuropsychological Tests (BRBN). Results: The overall prevalence of cognitive dysfunction in our patients was 52.8% with CIS patients excluded and 47.5% with CIS patients included. All MS patients differed significantly from controls in all BRBN measures. Similar was the pattern of cognitive dysfunction in patients with CIS suggestive of MS, although verbal learning/memory capacity (as measured by the Selective Reminding Test) remained relatively spared. The comparisons between patient groups revealed some differences in the performance mainly in favor of CIS and RRMS patients. These differences largely disappeared after controlling for physical disability (EDSS). Conclusion: All MS subtypes patients exhibit a pattern of cognitive impairment running across the studied cognitive domains. The pattern of cognitive dysfunction in patients with CIS is similar with relative sparing of verbal learning. (C) 2007 Elsevier B.V. All rights reserved