Incidence Of Post-stroke Dementia Research Articles

The role of cerebral microbleeds in the incidence of post-stroke dementia

Microbleeds are a marker of cerebrovascular disease however its role in incident post-stroke dementia (PSD) remains unclear. We investigated whether microbleeds are associated with incident PSD, domain-specific cognitive impairment and cognitive decline over a 2-year follow-up; and whether microbleeds interact with acute stroke-related infarcts to synergistically affect cognitive outcomes. In a cohort of patients with first-episode mild ischemic stroke and no pre-stroke dementia, we found patients with 3 or more mixed microbleeds (presence of both lobar and deep) were 4 times more at risk of developing PSD compared to patients with no microbleeds. Patients with strictly lobar microbleeds were 10 times more at risk of developing memory impairment while patients with possible CAA-related microbleeds were 8 times more at risk of developing memory impairment compared to patients with no microbleeds. Microbleeds did not predict cognitive decline at the 2-year follow-up. Acute stroke infarcts were not related to any cognitive outcomes. Microbleeds did not interact with stroke infracts to synergistically affect cognitive outcomes. Our findings suggest that the combined effect of possible CAA and hypertension-related microbleeds play a large and direct role in incident PSD. Management of vasculopathy and amyloid deposition may positively impact cognitive outcomes after stroke.

Anaemia and incidence of post stroke dementia

ObjectivesTo assess the impact of anaemia on incidence of post-stroke dementia. Patients and MethodsWe used data from a UK regional stroke register. To be eligible, patient must have survived to discharge and had anaemia by WHO criteria. Dementia status and other prevalent co-morbidities were assessed using ICD-10 codes. Patients were followed till May 2015 (mean follow-up 3.7 years, total person years = 27,769). Hazard Ratio for incident dementia was calculated using Cox-proportional hazards model controlling for potential confounders. Fine and Gray model was additionally constructed using mortality as the competing risk. ResultsA total of 7454 stroke patients were included with mean age SD of 75.912.3 years 50.2 % men). Those with anaemia were older, has higher disability and co-morbidity burden prior to stroke. We observed a large amount of variation in the dementia incidence rates over time and that the hazard ratio increased every year. The significant association between anaemia and dementia incidence was lost after controlling for pre-stroke Modified Rankin score (HR1.17(0.97,1.40)). With every 20 g/dL increase in Hb was associated with a significant reduction in the risk of dementia after adjustment for age, sex, stroke factors and disability but lost significance after adjustment for vascular risk factors. Competing risk analyses showed similar results. ConclusionWhilst we found no evidence of anaemia as a risk factor for post-stroke dementia, the findings may be limited by potential under recognition of post stroke dementia.

Abstract WP552: Post-stroke Dementia Incidence and Risk Factors in Korea: Linked Big Data Between the Clinical Research Center for Stroke Data and the Health Insurance Review & Assessment Service Data Analysis

Background: Post-stroke dementia is an important factor of poor functional outcome following stroke. However, few longitudinal studies on the incidence and risk factors of dementia after stroke have been performed. Hypothesis: We aimed to investigate the incidence and clinical factors related to dementia after ischemic stroke. Methods: A total of 47,779 patients with acute ischemic stroke (within 7 days after stroke onset) were enrolled, who were registered in the Clinical Research Center for Stroke (CRCS) registry from 2006 to 2014 and successfully linked the Health Insurance Review and Assessment Service (HIRA) big database. All included patients did not have dementia before index stroke. The incidence of post-stroke dementia was identified using International Classification of Diseases, Tenth Revision, dementia diagnosis codes (F00, F01, F02, F03, and G30) with prescription of an anti-dementia medications after index stroke based on linked big data. Results: Of the 47,779 patients, 10,357 patients (21.7%) had post-stroke dementia. The cumulative incidence of dementia after stroke was 10.4% after 1 year, 15.6 % after 3 years, 19.5% after 5 years, 22.9% after 7 years, and 27.1% after 10 years. The crude incidence rate of post-stroke dementia was 40.03 cases per 1000 person-years in this stroke registry based linkage big data. Post-stroke dementia groups were older, more frequently female, and were more likely to have severe stroke, history of stroke, lower education level, dependency before stroke. Conclusions: Our study demonstrated that about 22% of ischemic stroke patients were demented after stroke, particularly were associated with history of stroke, and stroke severity. These patients with high risk of dementia should be controlled risk factors for preventing cognitive impairment following stroke.

Assessment of cognitive functions in patients with metabolic syndrome after ischemic stroke

Post-stroke cognitive impairment (PSCI) occupies a prominent position among cognitive impairment associated with vascular brain pathology. The purpose – to assess cognitive functions in patients with the history of ischemic stroke, depending on the metabolic syndrome (MS) presence and to determine the peculiarities of cognitive functions dynamics in the early recovery period after ischemic stroke in the anterior circulation area in patients with and without metabolic syndrome depending on ischemic lesion localization. Materials and methods. There were 122 patients in the early recovery period after ischemic stroke enrolled into the study. Depending on the MS presence, patients with the history of ischemic stroke were divided into 2 groups: with MS (n = 72) and without MS (n = 50). All the patients were divided into 3 age subgroups: 45 – 59 years – middle age, 60 – 74 years – elderly, 75 – 89 years - senile age. All patients had general clinical, neuropsychological examination, laboratory tests; MRI of the brain. Results. There was no significant difference among patients of the main clinical groups on the frequency of pre-mild and mild cognitive impairment; however the incidence of post-stroke dementia was significantly higher among patients with MS comparing with those without MS. There was significant augmentation of PSCI severity with age in patients with MS and without it. According to the results of neuropsychological tests, the best cognitive functions recovery in 6 months after the stroke (in the early recovery period) was observed in patients without MS, especially in the cases of left hemisphere ischemic lesions. Conclusions. Patients with MS had significantly more pronounced PSCI than patients without MS. The increase in age had a negative effect on the PSCI severity both in patients with and without metabolic syndrome. The presence of MS worsened the process of cognitive functions restoration in patients with PSCI.

Prediction of post-stroke dementia using NINDS-CSN 5-minute neuropsychology protocol in acute stroke.

The National Institute of Neurological Disease and Stroke-Canadian Stroke Network (NINDS-CSN) 5-minute neuropsychology protocol consists of only verbal tasks, and is proposed as a brief screening method for vascular cognitive impairment. We evaluated its feasibility within two weeks after stroke and ability to predict the development of post-stroke dementia (PSD) at 3 months after stroke. We prospectively enrolled subjects with ischemic stroke within seven days of symptom onset who were consecutively admitted to 12 university hospitals. Neuropsychological assessments using the NINDS-CSN 5-minute and 60-minute neuropsychology protocols were administered within two weeks and at 3 months after stroke onset, respectively. PSD was diagnosed with reference to the American Heart Association/American Stroke Association statement, requiring deficits in at least two cognitive domains. Of 620 patients, 512 (82.6%) were feasible for the NINDS-CSN 5-minute protocol within two weeks after stroke. The incidence of PSD was 16.2% in 308 subjects who had completed follow-up at 3 months after stroke onset. The total score of the NINDS-CSN 5-minute protocol differed significantly between those with and without PSD (4.0 ± 2.7, 7.4 ± 2.7, respectively; p < 0.01). A cut-off value of 6/7 showed reasonable discriminative power (sensitivity 0.82, specificity 0.67, AUC 0.74). The NINDS-CSN 5-minute protocol score was a significant predictor for PSD (adjusted odds ratio 6.32, 95% CI 2.65-15.05). The NINDS-CSN 5-minute protocol is feasible to evaluate cognitive functions in patients with acute ischemic stroke. It might be a useful screening method for early identification of high-risk groups for PSD.

Physiologic Reelin does not play a strong role in protection against acute stroke

Stroke and Alzheimer's disease, two diseases that disproportionately affect the aging population, share a subset of pathological findings and risk factors. The primary genetic risk factor after age for late-onset Alzheimer's disease, ApoE4, has also been shown to increase stroke risk and the incidence of post-stroke dementia. One mechanism by which ApoE4 contributes to disease is by inducing in neurons a resistance to Reelin, a neuromodulator that enhances synaptic function. Previous studies in Reelin knockout mice suggest a role for Reelin in protection against stroke; however, these studies were limited by the developmental requirement for Reelin in neuronal migration. To address the question of the effect of Reelin loss on stroke susceptibility in an architecturally normal brain, we utilized a novel mouse with induced genetic reduction of Reelin. We found that after transient middle cerebral artery occlusion, mice with complete adult loss of Reelin exhibited a similar level of functional deficit and extent of infarct as control mice. Together, these results suggest that physiological Reelin does not play a strong role in protection against stroke pathology.

The Effect of Different Diagnostic Criteria on the Prevalence and Incidence of Post-Stroke Dementia

There is little agreement about the prevalence and incidence of vascular dementia (VaD) mainly because investigators have used different diagnostic criteria. The aim of this study was to examine the influence of different diagnostic criteria on the prevalence and cumulative incidence of VaD in first-ever stroke patients (n = 194) clinically evaluated at 1, 6, 12, and 24 months after stroke. Post-stroke VaD was diagnosed using the DSM-III, DSM-III-R, DSM-IV, ICD-10-NA, NINDS-AIREN, and ADDTC criteria. The prevalence of dementia was highest at 1 month; ranging from 11.3% with the NINDS-AIREN to 20.1% with the ICD-10-NA. The incidence was highest at 6 months, ranging from 2.6% with the ADDTC to 5.2% with the ICD-10-NA. Agreement among diagnostic criteria was high, with the exception of the ADDTC. In conclusion, both the prevalence and incidence of dementia are highest directly after stroke, but exact rates are influenced by the diagnostic criteria used.