Post-stroke memory impairment among patients with vascular mild cognitive impairment

Sex Differences in Poststroke Cognitive Impairment: A Multicenter Study in 2343 Patients With Acute Ischemic Stroke

BACKGROUND

Poststroke cognitive impairment (PSCI) occurs in about half of stroke survivors. Cumulative evidence indicates that functional outcomes of stroke are worse in women than men. Yet it is unknown whether the occurrence and characteristics of PSCI differ between men and women.

METHODS

Individual patient data from 9 cohorts of patients with ischemic stroke were harmonized and pooled through the Meta-VCI-Map consortium (n=2343, 38% women). We included patients with visible symptomatic infarcts on computed tomography/magnetic resonance imaging and cognitive assessment within 15 months after stroke. PSCI was defined as impairment in ≥1 cognitive domains on neuropsychological assessment. Logistic regression analyses were performed to compare men to women, adjusted for study cohort, to obtain odds ratios for PSCI and individual cognitive domains. We also explored sensitivity and specificity of cognitive screening tools for detecting PSCI, according to sex (Mini-Mental State Examination, 4 cohorts, n=1814; Montreal Cognitive Assessment, 3 cohorts, n=278).

RESULTS

PSCI was found in 51% of both women and men. Men had a lower risk of impairment of attention and executive functioning (men: odds ratio, 0.76 [95% CI, 0.61-0.96]), and language (men: odds ratio, 0.67 [95% CI, 0.45-0.85]), but a higher risk of verbal memory impairment (men: odds ratio, 1.43 [95% CI, 1.17-1.75]). The sensitivity of Mini-Mental State Examination (<25) for PSCI was higher for women (0.53) than for men (0.27; P=0.02), with a lower specificity for women (0.80) than men (0.96; P=0.01). Sensitivity and specificity of Montreal Cognitive Assessment (<26.) for PSCI was comparable between women and men (0.91 versus 0.86; P=0.62 and 0.29 versus 0.28; P=0.86, respectively).

CONCLUSIONS

Sex was not associated with PSCI occurrence but affected domains differed between men and women. The latter may explain why sensitivity of the Mini-Mental State Examination for detecting PSCI was higher in women with a lower specificity compared with men. These sex differences need to be considered when screening for and diagnosing PSCI in clinical practice.

Men Are at Higher Risk of Screening Positive for Vascular Cognitive Impairment Compared to Women after Stroke and Transient Ischemic Attack

While women have greater incidence of dementia, men have higher prevalence of vascular risk factors. This study examined sex differences in risk of screening positive for cognitive impairment after stroke. Ischemic stroke/TIA patients (N = 5969) participated in this prospective, multi-centered study, which screened for cognitive impairment using a validated brief screen. Men showed a higher risk of screening positive for cognitive impairment after adjusting for age, education, stroke severity, and vascular risk factors, suggesting that other factors may be contributing to increased risk among men (OR = 1.34, CI 95% [1.16, 1.55], p < 0.001). The effect of sex on cognitive impairment after stroke warrants further attention.

Chinese version of the auditory verbal learning test: normative study and clinical applications in Chinese-speaking population in Shijiazhuang city

OBJECTIVE

The purposes were to establish standardized values for the Auditory Verbal Learning Test (AVLT) in the communities of Shijiazhuang city (China), with particular focus on the influences of age, education and sex, and to detect the discriminant validity data of the AVLT in patients with acute ischemic stroke (AIS).

METHODS

406 Chinese-speaking subjects (age: 50-84 years old) from Shijiazhuang city, were brought into this study. Using linear regression analyses, standardized values were developed for three variables of interest, including scores on short-term memory (sum of AVLT trials 1-3), delayed recall (AVLT trial 4), and an index representing recognition memory corrected for false-positive identifications (AVLT trial 5). 177 patients with AIS were included to probe the discriminant validity of the AVLT.

RESULTS

The linear regression analysis showed statistically significant effect of age and sex on all trials of the AVLT. Years of education contributed significantly to trial 1-3 and trial 4 but not trial 5. Based on the results obtained, trail 1-3 and trail 4 of AVLT norms were stratified by age (3 strata), education (2 strata), and sex (2 strata). Trail 5 norms were stratified by age (3 strata) and sex (2 strata). Moreover, AIS groups performed significantly worse on most AVLT trials than matched cognitively healthy controls.

CONCLUSIONS

Normative data stratified by age, education and sex for the Chinese-speaking community-residents in Shijiazhuang was presented for use in research and clinical settings. The AVLT measures adequately differentiated between the cognitive performance (especially memory decline) of healthy adults and patients with AIS.

Revealing the Influences of Sex Hormones and Sex Differences in Atrial Fibrillation and Vascular Cognitive Impairment

The impacts of sex differences on the biology of various organ systems and the influences of sex hormones on modulating health and disease have become increasingly relevant in clinical and biomedical research. A growing body of evidence has recently suggested fundamental sex differences in cardiovascular and cognitive function, including anatomy, pathophysiology, incidence and age of disease onset, symptoms affecting disease diagnosis, disease severity, progression, and treatment responses and outcomes. Atrial fibrillation (AF) is currently recognized as the most prevalent sustained arrhythmia and might contribute to the pathogenesis and progression of vascular cognitive impairment (VCI), including a range of cognitive deficits, from mild cognitive impairment to dementia. In this review, we describe sex-based differences and sex hormone functions in the physiology of the brain and vasculature and the pathophysiology of disorders therein, with special emphasis on AF and VCI. Deciphering how sex hormones and their receptor signaling (estrogen and androgen receptors) potentially impact on sex differences could help to reveal disease links between AF and VCI and identify therapeutic targets that may lead to potentially novel therapeutic interventions early in the disease course of AF and VCI.

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

BACKGROUND/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.

The Relationship between Cerebral White Matter Integrity and Cognitive Function in Mild Stroke with Basal Ganglia Region Infarcts

Mild stroke is a known risk factor for dementia. The relationship between cerebral white matter (WM) integrity and cognitive impairment (CI) in mild stroke patients with basal ganglia region infarcts is unknown. Total of 33 stroke patients and 19 age-matched controls underwent diffusion tensor imaging scans and a formal neuropsychological test battery. CI was defined as having a performance score 1.5 SD below the established norm. We compared the differences in Z-scores and Fraction Anisotropy (FA) values among controls, stroke with no CI (NCI) and stroke with CI groups. Multiple linear regressions were performed between FA values in affected regions and neuropsychological tests in stroke patients. The majority of stroke patients were in their 50s (56.90 ± 9.23 years). CI patients exhibited a significantly decreased Z score in visual delayed memory and remarkably decreased FA values in the right external capsule and right fornix (FWE-corrected) compared with NCI patients and controls. In stroke patients, the FA value in the right fornix was positively correlated with delayed visual memory. Mild stroke with basal ganglia region infarcts may be related to widespread abnormality of WM integrity. The lower WM integrity in the right fornix may be a marker of impaired delayed visual memory.

A Systematic Review of the Definitions of Vascular Cognitive Impairment, No Dementia in Cohort Studies

BACKGROUND/AIMS

No set operational criteria for vascular cognitive impairment, no dementia (VCI-ND) have yet been established. The aim of this study is to undertake a systematic review to compare definitions of VCI-ND that have been used in cohort studies.

METHODS

Medline, PsycINFO and Embase were searched from inception to October 13, 2015. Initially, 3,142 records were screened, and 30 were included in this review.

RESULTS

No single set of criteria for defining VCI-ND was identified. VCI-ND was broadly defined as an absence of dementia, cognitive impairment in at least one cognitive domain with signs of vascular involvement, and intact activities of daily living.

CONCLUSION

Defining criteria will enable individuals with VCI-ND to be efficiently compared across cohort studies to more accurately determine the prevalence and risk of dementia.

Association between serum non-high-density lipoprotein cholesterol and cognitive impairment in patients with acute ischemic stroke

Background

Non-high density lipoprotein cholesterol (HDL-C) could be a good predictor of vascular disease outcomes. To evaluate the association between serum non-HDL-C and cognitive impairment in patients with acute ischemic stroke.

Methods

A total of 725 hospitalized patients with acute ischemic stroke were enrolled. They received conventional treatment. Cognitive function was assessed on the 3rd day after admission using mini-mental state examination (MMSE), Montreal Cognitive Assessment (MoCA), Activity of Daily Living Scale (ADL), and Neuropsychiatric Inventory (NPI, and Hamilton depression rating scale 21-item (HAMD-21). Lipid profile and biochemical markers were measured, and non-HDL-C was calculated.

Results

Compared with patients with normal non-HDL-C, those with high non-HDL-C showed lower MMSE (23.1 ± 4.9 vs. 26.0 ± 4.6, P < 0.001) and MoCA (20.4 ± 6.4 vs. 22.2 ± 5.3 P = 0.01) scores, higher NPI (6.2 ± 1.2 vs. 3.3 ± 1.5, P < 0.001) and HADM-21 (6.0 ± 2.2 vs. 4.5 ± 1.9, P < 0.001) scores, and higher homocysteine (16.0 ± 3.8 vs. 14.3 ± 2.0 mmol/L, P = 0.044), fasting blood glucose (6.4 ± 2.7 vs. 6.1 ± 2.1 mmol/L, P = 0.041), and HbA1c (6.80 ± 1.32 % vs. 6.52 ± 1.17 %, P = 0.013) levels. MMSE (r = -0.526, P < 0.001), MoCA (r = −0.216, P < 0.001), and NPI (r = 0.403, P < 0.001) scores were correlated with non-HDL-C levels. High non-HDL-C levels were an independent risk factor for cognitive disorders after acute ischemic stroke (P = 0.034, odds ratio = 3.115, 95 % confidence interval: 1.088–8.917).

Conclusions

High serum non-HDL-C levels, age, education, homocysteine levels, and HAMD score were independent risk factors of cognitive impairment in patients with acute ischemic stroke. The risk of cognitive disorders after acute ischemic stroke increased with increasing non-HDL-C levels. This parameter is easy to assess in the clinical setting.