Long-term structural brain changes in adult rats after mild ischaemic stroke.
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ABSTRACT:
SUBMITTER: Syeda W
PROVIDER: S-EPMC9309495 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:BACKGROUND:We identify cognitive impairment and MRI structural brain changes in long-term oligodendroglial tumor survivors treated with radiation therapy (RT) alone (21%) or with chemotherapy (CT) (79%). METHODS:Oligodendroglial tumor patients (based on the World Health Organization [WHO] 2007 classification) who completed RT ± CT at least 2 years before the study initiation, were classified into 3 groups according to the time treatment was completed: Group 1 = 2-5 years (n = 22), Group 2 = 6-10 years (n = 13), and Group 3 >10 years (n = 13). All patients had a cross-sectional neuropsychological evaluation (n = 48) and a longitudinal volumetric analysis (gray matter [GM; n = 34]) between postsurgical and last follow-up MRI. White matter (WM) changes on MRI were assessed using a qualitative scale. RESULTS:There were no differences regarding tumor or treatment-related characteristics between groups. Six of 22 patients (27.3%) in Group 1; 5/13 (38.5%) in Group 2; and 9/13 (69.2%) in Group 3 had cognitive impairment that was considered severe in 3/22 patients (13.6%) in Group 1; 4/13 (30.8%) in Group 2; and 6/13 (46.2%) in Group 3. Patients in Groups 2 and 3 showed significant GM atrophy and more leukoencephalopathy than Group 1. Cognitive deficits were associated with brain atrophy and WM changes. CONCLUSIONS:Long-term oligodendroglial tumor survivors who underwent standard RT ± CT treatment, mainly >5 years of its completion, present cognitive impairment, especially on memory and executive functions, associated with late GM and WM damage, thus highlighting the need of developing future strategies in patients with oligodendroglial tumor and long expected survival.
| S-EPMC6827827 | biostudies-literature
Project description:Recurrent stroke affects 9% to 15% of people within 1 year. This European Stroke Organisation (ESO) guideline provides evidence-based recommendations on pharmacological management of blood pressure (BP), diabetes mellitus, lipid levels and antiplatelet therapy for the prevention of recurrent stroke and other important outcomes in people with ischaemic stroke or transient ischaemic attack (TIA). It does not cover interventions for specific causes of stroke, including anticoagulation for cardioembolic stroke, which are addressed in other guidelines. This guideline was developed through ESO standard operating procedures and the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) methodology. The working group identified clinical questions, selected outcomes, performed systematic reviews, with meta-analyses where appropriate, and made evidence-based recommendations, with expert consensus statements where evidence was insufficient to support a recommendation. To reduce the long-term risk of recurrent stroke or other important outcomes after ischaemic stroke or TIA, we recommend: BP lowering treatment to a target of <130/80 mmHg, except in subgroups at increased risk of harm; HMGCoA-reductase inhibitors (statins) and targeting a low density lipoprotein level of <1.8 mmol/l (70 mg/dl); avoidance of dual antiplatelet therapy with aspirin and clopidogrel after the first 90 days; to not give direct oral anticoagulant drugs (DOACs) for embolic stroke of undetermined source and to consider pioglitazone in people with diabetes or insulin resistance, after careful consideration of potential risks. In addition to the evidence-based recommendations, all or the majority of working group members supported: out-of-office BP monitoring; use of combination treatment for BP control; consideration of ezetimibe or PCSK9 inhibitors when lipid targets are not achieved; consideration of use of low-dose DOACs in addition to an antiplatelet in selected groups of people with coronary or peripheral artery disease and aiming for an HbA1c level of <53 mmol/mol (7%) in people with diabetes mellitus. These guidelines aim to standardise long-term pharmacological treatment to reduce the burden of recurrent stroke in Europe.
| S-EPMC9446324 | biostudies-literature
Project description:Aims:There is a paucity of data on the influence of diabetes on long-term outcomes after ischaemic stroke (IS). We assessed whether outcomes after IS differ between patients with and without diabetes. Methods and results:Patients aged ≥65 years (n = 409 060) in Get With The Guidelines-Stroke (nationwide registry of stroke patients from 1690 sites in the USA) were followed for 3 years post-discharge. The outcomes of interest were mortality, cardiovascular and non-cardiovascular hospitalizations, heart failure (HF), and recurrence of IS/transient ischaemic attack (TIA). Patients with diabetes (29.6%) were younger and had more comorbidities. At 3 years post-discharge after IS, diabetes was associated with higher risks of adverse outcomes: all-cause mortality [cumulative incidence 46.0% vs. 44.2%, absolute difference (AD) 1.8%; adjusted hazard ratio (aHR) 1.24, 95% confidence interval 1.23-1.25], all-cause readmission (71.3% vs. 63.7%, AD 7.6%; aHR 1.22, 1.21-1.23), composite of mortality and all-cause readmission (84.1% vs. 79.3%, AD 4.8%; aHR 1.21, 1.20-1.22), composite of mortality and cardiovascular readmission (69.5% vs. 64.3%, AD 5.2%; aHR 1.19, 1.18-1.20), IS/TIA readmission (15.9% vs. 13.3%, AD 2.6%; aHR 1.18, 1.16-1.20), HF readmission (10.3% vs. 6.4%, AD 3.9%; aHR 1.60, 1.56-1.64), non-cardiovascular readmission (58.3% vs. 50.3%, AD 8.0%; aHR 1.28, 1.26-1.29), and non-IS/TIA readmission (67.6% vs. 59.7%, AD 7.9%; aHR 1.23, 1.22-1.25). Accounting for the initial severity of stroke using the National Institute of Health Stroke Scale as well as using propensity score matching method as a sensitivity analysis, did not modify the results. Conclusion:Among older IS patients diabetes was associated with increased risks of death, cardiovascular and non-cardiovascular hospitalizations, HF, and IS/TIA recurrence.
| S-EPMC6031049 | biostudies-literature
Project description:AimsPre-operatively diagnosed patent foramen ovale (PFO) is associated with an increased risk of ischaemic stroke within 30 days after surgery. This study aimed to assess the PFO-attributable ischaemic stroke risk beyond the perioperative period.Methods and resultsThis observational study of adult patients without history of stroke undergoing non-cardiac surgery with general anaesthesia examined the association of PFO with ischaemic stroke 1 and 2 years after surgery using multivariable logistic regression. Of the 144 563 patients included, a total of 1642 (1.1%) and 2376 (1.6%) ischaemic strokes occurred within 1 and 2 years after surgery, 54 (4.7%) and 76 (6.6%) among patients with PFO, and 1588 (1.1%) and 2300 (1.6%) among patients without PFO, respectively. The odds of ischaemic stroke within 1 and 2 years after surgery were increased in patients with PFO: adjusted odds ratio (aOR) 2.01, 95% confidence interval (CI) 1.51-2.69; P < 0.001 and aOR 2.10, 95% CI 1.64-2.68; P < 0.001, respectively. Among patients who underwent contrast transoesophageal echocardiography, the frequency of PFO was 27%, and the increased stroke risk in patients with PFO was robust (aOR 3.80, 95% CI 1.76-8.23; P = 0.001 for year 1). The PFO-attributable risk was mitigated by post-operative prescription of combination antithrombotic therapy (odds ratio 0.41, 95% CI 0.22-0.75; P for interaction = 0.004).ConclusionPatients with PFO are vulnerable to ischaemic stroke for an extended period of time after surgery. Physicians should consider implementing PFO screening protocols in patients scheduled for major non-cardiac surgery.
| S-EPMC6416532 | biostudies-literature
Project description:Background and purposeInformation on the prevalence and course of post-stroke cognitive impairment in young stroke patients is limited. The aim was to assess a consecutive sample of acute young ischaemic stroke patients (18-55 years) for the presence and development of neuropsychological deficits.MethodsPatients prospectively underwent a comprehensive clinical and cognitive assessment, examining general cognitive function, processing speed, attention, flexibility/executive function and word fluency within the first 3 weeks after hospital admission (median assessment at day 6) and at a 3 months' follow-up (FU). Cognitive dysfunction was defined in comparison to age-standardized published norms.ResultsAt baseline (N = 114), deficits were highly prevalent in processing speed (56.0%), flexibility/executive function (49.5%), attention (46.4%) and general cognitive function (42.1%). These frequencies were comparable for those with FU assessment (N = 87). In most domains, cognitive performance improved within 3 months, except for word fluency. However, in about one-third of patients, cognitive deficits (as defined by 1.5 standard deviations below the standardized mean) were still present 3 months after stroke. At FU, 44.0% were impaired in the domain flexibility/executive function, 35.0% in processing speed and 30.0% in attention.ConclusionsThe high prevalence of cognitive deficits in acute young patients with ischaemic stroke highlights the importance of early post-stroke cognitive assessment to capture a patient's dysfunction in a comprehensive manner and to offer adequate rehabilitation. The role of factors which promote neuropsychological deficits needs further exploration.
| S-EPMC6491967 | biostudies-literature
Project description:ObjectiveWe examined the association between initiation of antidepressants within the first year after ischaemic stroke (IS) in young adults and long-term fatal and non-fatal cardiovascular events, as well as all-cause mortality.Patients and methodsThe Helsinki Young Stroke Registry (HYSR) includes patients aged 15-49 years with their first-ever IS occurring 1994-2007. From nationwide registers, we obtained data on prescriptions (1993-2011) and outcomes of interest (1994-2011). Time of initiating post-stroke antidepressants (PSADs) was defined as time of the first filled prescription for antidepressants within the first year from IS. To account for non-random assignment of PSADs, we performed propensity score matching and studied the relationship between PSAD initiation and outcomes using Cox regression models with time-varying coefficients.ResultsOf all patients (n = 888), 206 (23.2%) initiated PSADs within the first year, of which 203 (98.5%) could be matched to 406 non-initiators. In this matched sample of 609 patients, the median follow-up time was 8.1 (interquartile range [IQR] 5.0-12.6) years and 169 (28.9%) patients had any cardiovascular events, 95 (15.8%) had recurrent ischaemic or haemorrhagic strokes and 106 (17.4%) died. Adjusted for sociodemographics and cardiovascular comorbidities, PSAD initiation was associated with recurrent ischaemic or haemorrhagic stroke 5-10 years after IS (hazard ratio [HR] 3.07, 95% confidence interval [CI] 1.32-7.12). No association emerged between PSAD initiation and other outcomes.ConclusionsIn young adults, PSAD initiation within the first year after IS was associated with a heightened hazard of recurrent ischaemic or haemorrhagic stroke in the long term. Future studies are needed to verify the results and to further study the nature of this finding.KEY MESSAGESInitiation of post-stroke antidepressants (PSADs) within the first year after ischaemic stroke (IS) was associated with a heightened hazard of recurrent ischaemic or haemorrhagic stroke in the long term.Patients starting antidepressants after IS should be followed up more closely in case of recurrent events.Future studies are needed to verify the results and to further study the nature of this finding.
| S-EPMC9258433 | biostudies-literature
Project description:Spinal cord injury (SCI)-induced bone loss represents the most severe osteoporosis with no effective treatment. Past animal studies have focused primarily on long bones at the acute stage using adolescent rodents. To mimic chronic SCI in human patients, we performed a comprehensive analysis of long-term structural and mechanical changes in axial and appendicular bones in adult rats after SCI. In this experiment, 4-month-old Fischer 344 male rats received a clinically relevant T13 contusion injury. Sixteen weeks later, sublesional femurs, tibiae, and L4 vertebrae, supralesional humeri, and blood were collected from these rats and additional non-surgery rats for micro-computed tomography (µCT), micro-finite element, histology, and serum biochemical analyses. At trabecular sites, extreme losses of bone structure and mechanical competence were detected in the metaphysis of sublesional long bones after SCI, while the subchondral part of the same bones showed much milder damage. Marked reductions in bone mass and strength were also observed in sublesional L4 vertebrae but not in supralesional humeri. At cortical sites, SCI induced structural and strength damage in both sub- and supralesional long bones. These changes were accompanied by diminished osteoblast number and activity and increased osteoclast number and activity. Taken together, our study revealed site-specific effects of SCI on bone and demonstrated sustained inhibition of bone formation and elevation of bone resorption at the chronic stage of SCI.
| S-EPMC4621491 | biostudies-other
Project description:A history of mild traumatic brain injury (mTBI), particularly repeated mTBI (rmTBI), has been identified as a risk factor for late-onset neurodegenerative conditions. The mild and transient nature of early symptoms often impedes diagnosis in young adults who are disproportionately affected by mTBIs. A proportion of the affected population will incur long-term behavioral and cognitive consequences but the underlying pathomechanism is currently unknown. Diffusion tensor imaging (DTI) provides sensitive and quantitative assessment of TBI-induced structural changes, including white matter injury, and may be used to predict long-term outcome. We used DTI in an animal model of blast rmTBI (rmbTBI) to quantify blast-induced structural changes at 7 and 90?days post-injury, and their evolution between the two time points. Young adult male rats (~P65 at injury) were exposed to repeated mild blast overpressure, or anesthetized as shams, and their fixed brains were imaged using high-field (7?T) MRI. We found that whole brain volumes similarly increased in injured and sham rats from 7 to 90?days. However, we detected localized volume increases in blast-exposed animals 7?days post-injury, mainly ipsilateral to incident blast waves. Affected regions included gray matter of the frontal association, cingulate, and motor cortex, thalamus, substantia nigra, and raphe nuclei (median and dorsal), as well as white matter of the internal capsule and cerebral peduncle. Conversely, we measured volume reductions in these and other regions, including the hippocampus and cerebellum, at 90?days post-injury. DTI also detected both transient and persistent microstructural changes following injury, with some changes showing distinct ipsilateral versus contralateral side differences relative to blast impact. Early changes in fractional anisotropy (FA) were subtle, becoming more prominent at 90?days in the cerebral and inferior cerebellar peduncles, and cerebellar white matter. Widespread increases in radial diffusivity (RD) and axial diffusivity (primary eigenvalue or E1) at 7?days post-injury largely subsided by 90?days, although RD was more sensitive than E1 at detecting white matter changes. E1 effects in gray and white matter, which paralleled increases in apparent diffusion, were likely more indicative of dysregulated water homeostasis than pathologic structural changes. Importantly, we found evidence for a different developmental trajectory following rmbTBI, as indicated by significant injury x age interactions on volume. Our findings demonstrate that rmbTBI initiates dynamic pathobiological processes that may negatively alter the course of late-stage neurodevelopment and adversely affect long-term cognitive and behavioral outcomes.
| S-EPMC5984602 | biostudies-literature
Project description:Over one-third of stroke patients has long-term cognitive impairment. The likelihood of cognitive dysfunction is poorly predicted by the location or size of the infarct. The macro-scale damage caused by ischaemic stroke is relatively localized, but the effects of stroke occur across the brain. Structural covariance networks represent voxelwise correlations in cortical morphometry. Atrophy and topographical changes within such distributed brain structural networks may contribute to cognitive decline after ischaemic stroke, but this has not been thoroughly investigated. We examined longitudinal changes in structural covariance networks in stroke patients and their relationship to domain-specific cognitive decline. Seventy-three patients (mean age, 67.41 years; SD = 12.13) were scanned with high-resolution magnetic resonance imaging at sub-acute (3 months) and chronic (1 year) timepoints after ischaemic stroke. Patients underwent a number of neuropsychological tests, assessing five cognitive domains including attention, executive function, language, memory and visuospatial function at each timepoint. Individual-level structural covariance network scores were derived from the sub-acute grey-matter probabilistic maps or changes in grey-matter probability maps from sub-acute to chronic using data-driven partial least squares method seeding at major nodes in six canonical high-order cognitive brain networks (i.e. dorsal attention, executive control, salience, default mode, language-related and memory networks). We then investigated co-varying patterns between structural covariance network scores within canonical distributed brain networks and domain-specific cognitive performance after ischaemic stroke, both cross-sectionally and longitudinally, using multivariate behavioural partial least squares correlation approach. We tested our models in an independent validation data set with matched imaging and behavioural testing and using split-half validation. We found that distributed degeneration in higher-order cognitive networks was associated with attention, executive function, language, memory and visuospatial function impairment in sub-acute stroke. From the sub-acute to the chronic timepoint, longitudinal structural co-varying patterns mirrored the baseline structural covariance networks, suggesting synchronized grey-matter volume decline occurred within established networks over time. The greatest changes, in terms of extent of distributed spatial co-varying patterns, were in the default mode and dorsal attention networks, whereas the rest were more focal. Importantly, faster degradation in these major cognitive structural covariance networks was associated with greater decline in attention, memory and language domains frequently impaired after stroke. Our findings suggest that sub-acute ischaemic stroke is associated with widespread degeneration of higher-order structural brain networks and degradation of these structural brain networks may contribute to longitudinal domain-specific cognitive dysfunction.
| S-EPMC7751023 | biostudies-literature
Project description:BackgroundStroke may have a major effect on survivors and on the healthcare system.AimsTo study the functional status and use of healthcare facilities in long-term survivors of a transient ischaemic attack (TIA) or minor ischaemic stroke (MIS) and evaluate associations with baseline and follow-up characteristics.MethodsFollow-up of patients who had participated in the Dutch TIA Trial or the European Atrial Fibrillation Trial was extended to a mean period of 15.6 years. Patients were interviewed through a postal questionnaire (n = 468) and a sample of this group was also interviewed at home (n = 198). Demographic data, information on comorbidity, functional status (Barthel Index, Frenchay Activities Index and modified Rankin Scale) and use of healthcare facilities were recorded.ResultsAbout one third of the survivors interviewed at home experienced any residual disability and 26% were moderately to severely handicapped. Factors associated with poor functional status were advanced age and the presence of any infarct on a baseline computed tomography scan, the recurrence of a new major stroke or the presence of comorbidity of locomotion. One third of survivors used any kind of professional care, which was predominantly related to the functional status at follow-up.ConclusionsRecurrent stroke and the presence of comorbidity of locomotion are important determinants of long-term disability of survivors of a TIA or an MIS, which, in turn, is strongly associated with the long-term use of professional care. The need for measuring comorbidity with regard to functional status is recommended in research on stroke outcome.
| S-EPMC2077397 | biostudies-literature