Profile of and risk factors for poststroke cognitive impairment in diverse ethno-regional groups

OBJECTIVE: To address the variability in prevalence estimates and inconsistencies in potential risk factors for poststroke cognitive impairment (PSCI) using a standardized approach and individual participant data (IPD) from international cohorts in the Stroke and Cognition Consortium (STROKOG) consortium. METHODS: We harmonized data from 13 studies based in 8 countries. Neuropsychological test scores 2 to 6 months after stroke or TIA and appropriate normative data were used to calculate standardized cognitive domain scores. Domain-specific impairment was based on percentile cutoffs from normative groups, and associations between domain scores and risk factors were examined with 1-stage IPD meta-analysis. RESULTS: In a combined sample of 3,146 participants admitted to hospital for stroke (97%) or TIA (3%), 44% were impaired in global cognition and 30% to 35% were impaired in individual domains 2 to 6 months after the index event. Diabetes mellitus and a history of stroke were strongly associated with poorer cognitive function after covariate adjustments; hypertension, smoking, and atrial fibrillation had weaker domain-specific associations. While there were no significant differences in domain impairment among ethno-racial groups, some interethnic differences were found in the effects of risk factors on cognition. CONCLUSIONS: This study confirms the high prevalence of PSCI in diverse populations, highlights common risk factors, in particular diabetes mellitus, and points to ethno-racial differences that warrant attention in the development of prevention strategies.OBJECTIVE: To address the variability in prevalence estimates and inconsistencies in potential risk factors for poststroke cognitive impairment (PSCI) using a standardized approach and individual participant data (IPD) from international cohorts in the Stroke and Cognition Consortium (STROKOG) consortium. METHODS: We harmonized data from 13 studies based in 8 countries. Neuropsychological test scores 2 to 6 months after stroke or TIA and appropriate normative data were used to calculate standardized cognitive domain scores. Domain-specific impairment was based on percentile cutoffs from normative groups, and associations between domain scores and risk factors were examined with 1-stage IPD meta-analysis. RESULTS: In a combined sample of 3,146 participants admitted to hospital for stroke (97%) or TIA (3%), 44% were impaired in global cognition and 30% to 35% were impaired in individual domains 2 to 6 months after the index event. Diabetes mellitus and a history of stroke were strongly associated with poorer cognitive function after covariate adjustments; hypertension, smoking, and atrial fibrillation had weaker domain-specific associations. While there were no significant differences in domain impairment among ethnoracial groups, some interethnic differences were found in the effects of risk factors on cognition. CONCLUSIONS: This study confirms the high prevalence of PSCI in diverse populations, highlights common risk factors, in particular diabetes mellitus, and points to ethnoracial differences that warrant attention in the development of prevention strategies.Peer reviewe

Prevalence of Poststroke Neurocognitive Disorders Using National Institute of Neurological Disorders and Stroke-Canadian Stroke Network, VASCOG Criteria (Vascular Behavioral and Cognitive Disorders), and Optimized Criteria of Cognitive Deficit

International audienceBackground and Purpose-The prevalence of poststroke neurocognitive disorder (NCD) has yet to be accurately determined. The primary objective of the present study was to optimize operationalization of the criterion for NCD by using an external validity criterion. Methods-The GRECOG-VASC cohort (Groupe de Reflexion pour l'Evaluation Cognitive Vasculaire) of 404 stroke patients with cerebral infarct (91.3%) or hemorrhage (18.7%) was assessed 6 months poststroke and 1003 healthy controls, with the National Institute of Neurological Disorders and Stroke-Canadian Stroke Network standardized battery. Three dimensions of the criterion for cognitive impairment were systematically examined by using the false-positive rate as an external validity criterion. Diagnosis of mild and major NCD was based on the VASCOG criteria (Vascular Behavioral and Cognitive Disorders). The mechanisms of functional decline were systematically assessed. Results-The optimal criterion for cognitive impairment was the shortened summary score (ie, averaged performance for action speed, executive functions, and language) because it was associated with the highest (P=0.0001) corrected true-positive rate (43.5%) and a false-positive rate <= 5%. Using this criterion, the mean (95% confidence interval) prevalence of poststroke NCD was 49.5% (44.6-54.4), most of which corresponded to mild NCD (39.1%; 95% confidence interval, 34.4-43.9) rather than dementia (10.4%; 95% confidence interval, 7.4-13.4). Conclusions-This study is the first to have optimized the operationalization of the criterion for poststroke cognitive impairment. It documented the prevalence of poststroke NCD in the GRECOG-VASC cohort and showed that mild cognitive impairment accounts for 80% of the affected patients. Finally, the method developed in the present study offers a means of harmonizing the diagnosis of NCD

Who should undergo a comprehensive cognitive assessment after a stroke? A cognitive risk score

International audienceObjective To validate the ability of a specifically developed cognitive risk score to identify patients at risk of poststroke neurocognitive disorders (NCDs) who are eligible for a comprehensive cognitive assessment. Methods After assessing 404 patients (infarct 91.3%) in the Groupe de Reflexion pour l'Evaluation Cognitive VASCulaire (GRECogVASC) cross-sectional study with the National Institute of Neurological Disorders and Stroke Canadian Stroke Network battery 6 months after stroke, we used multivariable logistic regression and bootstrap analyses to determine factors associated with NCDs. Independent, internally validated factors were included in a cognitive risk score. Results Cognitive impairment was present in 170 of the 320 patients with a Rankin Scale score The backward logistic regression selected 4 factors (>= 73% of the permutations): NIH Stroke Scale score on admission >= 7 (odds ratio [OR] 2.73, 95% confidence interval [CI] 1.29-4.3, p = 0.005), multiple strokes (OR 3.78, 95% CI 1.6-8, p = 0.002), adjusted Mini-Mental State Examination (MMSEadj) score = 2 (OR 2.34, 95% CI 1.3-4.2, p = 0.004). The cognitive risk score computed with these 4 factors provided good calibration, discrimination (overoptimism-corrected C = 0.793), and goodness of fit (Hosmer-Lemeshow test p 0.99). A combination of Rankin Scale score >= 1, cognitive risk score >= 1 and MMSEadj score >= 21 selected 230 (56.9%) of the 404 patients for a comprehensive assessment. This procedure yielded good sensitivity (96.5%) and moderate specificity (43%; positive predictive value 0.66, negative predictive value 0.91) and was more accurate (p <= 0.03 for all) than the sole use of screening tests (MMSE or Montreal Cognitive Assessment). Conclusion The GRECogVASC cognitive risk score comprises 4 easily documented factors; this procedure helps to identify patients at risk of poststroke NCDs who must therefore undergo a comprehensive assessment. ClinicalTrials.gov identifier: NCT01339195

Systematic Review and Meta-Analysis of Prevalence in Post-Stroke Neurocognitive Disorders in Hospital-Based Studies

International audienceBackground/Aims: Post-stroke neurocognitive disorders (post-stroke NCD) have been reported with a very variable prevalence. Methods: Based on a systematic literature search, hospital-based studies published between January 1990 and September 2015 were selected when they reported the prevalence of total, mild, and major post-stroke NCD diagnosed by using specified criteria. Factors affecting prevalence were assessed using meta-regression analysis. Results: Among the 7,440 references evaluated, 16 hospital-based studies were selected, corresponding to a total of 3,087 patients. The overall prevalence of total post-stroke NCD was 53.4% (95% CI: 46.9-59.8): 36.4% for mild post-stroke NCD (95% CI: 29-43.8) and 16.5% (95% CI: 12.1-20.8) for major post-stroke NCD. The overall prevalence was mainly influenced by the threshold score used for categorization (p = 0.0001) and, in the subgroup of studies using a conservative threshold (i.e., <= 7th percentile), by the recurrent stroke rate (p = 0.0005). The prevalence of major post-stroke NCD was mainly influenced by age (p = 0.003). Conclusion: More than half of stroke survivors experience post-stroke NCD, corresponding to mild post-stroke NCD in two-thirds of cases and major post-stroke NCD in one-third of cases. Harmonization of stroke assessment and cognitive score thresholds is urgently needed to allow more accurate estimation of post-stroke NCD prevalence, especially mild post-stroke NCD. (C) 2018 S. Karger AG, Base

Profile of and risk factors for poststroke cognitive impairment in diverse ethnoregional groups

10.1212/WNL.0000000000008612NEUROLOGY9324E2257-E227

Network impact score is an independent predictor of post-stroke cognitive impairment: A multicenter cohort study in 2341 patients with acute ischemic stroke

International audienceBackground: Post-stroke cognitive impairment (PSCI) is a common consequence of stroke. Accurate prediction of PSCI risk is challenging. The recently developed network impact score, which integrates information on infarct location and size with brain network topology, may improve PSCI risk prediction. Aims: To determine if the network impact score is an independent predictor of PSCI, and of cognitive recovery or decline. Methods: We pooled data from patients with acute ischemic stroke from 12 cohorts through the Meta VCI Map consortium. PSCI was defined as impairment in & GE; 1 cognitive domain on neuropsychological examination, or abnormal Montreal Cognitive Assessment. Cognitive recovery was defined as conversion from PSCI 24 months) and cognitive recovery or decline using logistic regression. Models were adjusted for age, sex, education, prior stroke, infarct volume, and study site. Results: We included 2341 patients with 4657 cognitive assessments. PSCI was present in 398/844 patients (47%) 24 months. Cognitive recovery occurred in 64/181 (35%) patients and cognitive decline in 26/287 (9%). The network impact score predicted PSCI in the univariable (OR 1.50, 95%CI 1.34-1.68) and multivariable (OR 1.27, 95%CI 1.10-1.46) GEE model, with similar ORs in the logistic regression models for specified post-stroke in-tervals. The network impact score was not associated with cognitive recovery or decline. Conclusions: The network impact score is an independent predictor of PSCI. As such, the network impact score may contribute to a more precise and individualized cognitive prognostication in patients with ischemic stroke. Future studies should address if multimodal prediction models, combining the network impact score with de-mographics, clinical characteristics and other advanced brain imaging biomarkers, will provide accurate indi-vidualized prediction of PSCI. A tool for calculating the network impact score is freely available at https ://metavcimap.org/features/software-tools/lsm-viewer/

Assessment of Mendelian and risk factor genes in Alzheimer disease: a prospective nationwide clinical utility study and recommendations for genetic screening

International audiencePurpose: To assess the likely pathogenic/pathogenic (LP/P) variants rates in Mendelian dementia genes and the moderate-to-strong risk factors rates in patients with Alzheimer disease (AD).Methods: We included 700 patients in a prospective study and performed exome sequencing. A panel of 28 Mendelian and 6 risk-factor genes was interpreted and returned to patients. We built a framework for risk variant interpretation and risk gradation and assessed the detection rates among early-onset AD (EOAD, age of onset (AOO) ≤65 years, n = 608) depending on AOO and pedigree structure and late-onset AD (66 &lt; AOO &lt; 75, n = 92).Results: Twenty-one patients carried a LP/P variant in a Mendelian gene (all with EOAD, 3.4%), 20 of 21 affected APP, PSEN1, or PSEN2. LP/P variant detection rates in EOAD ranged from 1.7% to 11.6% based on AOO and pedigree structure. Risk factors were found in 69.5% of the remaining 679 patients, including 83 (12.2%) being heterozygotes for rare risk variants, in decreasing order of frequency, in TREM2, ABCA7, ATP8B4, SORL1, and ABCA1, including 5 heterozygotes for multiple rare risk variants, suggesting non-monogenic inheritance, even in some autosomal-dominant-like pedigrees.Conclusion: We suggest that genetic screening should be proposed to all EOAD patients and should no longer be prioritized based on pedigree structure