Trait anxiety: a hidden variable in physiological and pathological processes

Nell\u2019uomo esiste una differenza nella risposta agli stimoli stressogeni, che dipende dalla personale predisposizione all\u2019ansia, detta specificatamente \u201ctratto d\u2019ansia\u201d. La differente suscettibilit\ue0 all\u2019ansia \ue8 stata studiata nei roditori creando ceppi selezionati per tratti di elevata e bassa ansia; inoltre \ue8 stato dimostrato, sia nell\u2019uomo che nei ceppi selezionati di roditori, che differenti livelli di ansia basale influenzano la capacit\ue0 dei soggetti di attuare un determinato compito, anche cognitivo. Tuttavia la suscettibilit\ue0 individuale, all\u2019interno di uno stesso ceppo di ratti na\uefve, \ue8 ancora poco studiata. Lo scopo di questo studio quindi \ue8 stato quello di valutare le possibili differenze interindividuali nel livello d\u2019ansia, all\u2019interno di una popolazione di ratti appartenenti al ceppo Wistar, e di fornire indicazioni su come uno specifico tratto d\u2019ansia possa influenzare una successiva performance cognitiva, valutata mediante un test cognitivo ampiamente utilizzato, il Novel Object Recognition (NOR) test. Seguendo questa linea di ricerca poi, abbiamo voluto indagare se il tratto di ansia potesse influenzare la suscettibilit\ue0 del ceppo di topo C57Bl/6J all\u2019insorgenza dell\u2019 epilessia, e se l\u2019esposizione ad un fattore fortemente stressogeno per il topo, l\u2019odore di un suo predatore, potesse provocare un aggravamento della malattia durante la fase cronica. Questo lavoro di tesi mostra come esista una variabilit\ue0 interindividuale all\u2019interno di una popolazione di roditori per quanto riguarda l\u2019ansia di tratto, cio\ue8 la componente basale di ansia insita in ogni individuo. Questo fattore pu\uf2 influenzare la risposta ad alcuni compiti a cui l\u2019animale deve rispondere, come ad esempio quelli cognitivi. Il tratto d\u2019ansia basale potrebbe anche influenzare la predisposizione all\u2019insorgenza di una determinata malattia, oppure il decorso della malattia stessa. E\u2019 perci\uf2 molto importante considerare il tratto d\u2019ansia basale di ciascun soggetto sperimentale in tutti gli studi che prevedano una componente comportamentale, includendo tale dato come fattore covariato nelle analisi statistiche, cos\uec da evitare errori dovuti a questa variabile nascosta.Human subjects display a great variability in the predisposition to respond anxiogenically to stimuli, i.e. trait anxiety. This susceptibility has been studied in rodents through the creation of selected strains for anxiety-like behaviour, to obtain extreme anxiety traits. Moreover, anxiety has been shown to variously affect physiological processes, such as a cognitive task performance, both in humans and selected rodents strains. However, interindividual differences in basal anxiety level in na\uefve rats and how they may affect cognitive functioning have been poorly investigated. Therefore, the aim of this study is to provide an evidence of the huge interindividual differences in anxiety levels in a population of na\uefve Wistar rats and demonstrate how they can affect a widely used cognitive test, the Novel Object Recognition (NOR) test. Following this line of research, in this study we also investigate if trait anxiety could affect pathological processes, such as the susceptibility on the onset of a neurological disease, the temporal lobe epilepsy, in a population of C57Bl/6J mice. Finally, we evaluate if the exposure to a strong stressful factor for mice, such as a predator odor, could induce an increase of the pathological process in chronic phase of the illness, for example in the number of seizures, in the same epileptic animals. These results could show the relevance to consider trait anxiety, the propension to response in a manner more or less anxious to a specific stimulus, of each subject, in order to avoid interpretative errors during the evaluation of a specific behaviour shown by the subject. Therefore we claim the need to consider interindividual differences in emotionality (e.g. anxiety) in general, and the need to assess anxiety level while studying rats cognitive abilities. It will be possible to include it as a covariate in the statistical analysis, in studies that schedule behavioural factors, in order to avoid interpretative errors dued to this hidden variable

Endovascular Treatment With or Without Prior Intravenous Alteplase for Acute Ischemic Stroke

Background It is unclear whether intravenous thrombolysis ( IVT ) with alteplase before endovascular treatment ( EVT ) is beneficial for patients with acute ischemic stroke caused by a large vessel occlusion. We compared clinical and procedural outcomes, safety, and workflow between patients treated with both IVT and EVT and those treated with EVT alone in routine clinical practice. Methods and Results Using multivariable regression, we evaluated the association of IVT + EVT with 90‐day functional outcome (modified Rankin Scale), mortality, reperfusion, first‐pass effect, and symptomatic intracranial hemorrhage in the MR CLEAN (Multicenter Randomised Controlled Trial of Endovascular Treatment for Acute Ischemic Stroke in The Netherlands) Registry. Of 1485 patients, 1161 (78%) were treated with IVT + EVT , and 324 (22%) with EVT alone. Patients treated with IVT + EVT had atrial fibrillation less often (16% versus 44%) and had better pre‐stroke modified Rankin Scale scores (pre‐stroke modified Rankin Scale 0: 73% versus 52%) than those treated with EVT alone. Procedure time was shorter in the IVT + EVT group (median 62 versus 68 minutes). Nontransferred IVT + EVT patients had longer door‐to‐groin‐puncture times (median 105 versus 94 minutes). IVT + EVT was associated with better functional outcome (adjusted common odds ratio 1.47; 95% CI : 1.10–1.96) and lower mortality (adjusted odds ratio 0.58; 95% CI : 0.40–0.82). Successful reperfusion, first‐pass effect, and symptomatic intracranial hemorrhage did not differ between groups. Conclusions In this observational study, patients treated with IVT + EVT had better clinical outcomes than patients who received EVT alone. This finding may demonstrate a true benefit of IVT before EVT , but its interpretation is hampered by the possibility of residual confounding and selection bias. Randomized trials are required to properly assess the effect of IVT before EVT . </jats:sec

Workflow Intervals of Endovascular Acute Stroke Therapy During On- Versus Off-Hours

Background and Purpose— Endovascular treatment (EVT) of patients with acute ischemic stroke because of large vessel occlusion involves complicated logistics, which may cause a delay in treatment initiation during off-hours. This might lead to a worse functional outcome. We compared workflow intervals between endovascular treatment–treated patients presenting during off- and on-hours. Methods— We retrospectively analyzed data from the MR CLEAN Registry, a prospective, multicenter, observational study in the Netherlands and included patients with an anterior circulation large vessel occlusion who presented between March 2014 and June 2016. Off-hours were defined as presentation on Monday to Friday between 17:00 and 08:00 hours, weekends (Friday 17:00 to Monday 8:00) and national holidays. Primary end point was first door to groin time. Secondary end points were functional outcome at 90 days (modified Rankin Scale) and workflow time intervals. We stratified for transfer status, adjusted for prognostic factors, and used linear and ordinal regression models. Results— We included 1488 patients of which 936 (62.9%) presented during off-hours. Median first door to groin time was 140 minutes (95% CI, 110–182) during off-hours and 121 minutes (95% CI, 85–157) during on-hours. Adjusted first door to groin time was 14.6 minutes (95% CI, 9.3–20.0) longer during off-hours. Door to needle times for intravenous therapy were slightly longer (3.5 minutes, 95% CI, 0.7–6.3) during off-hours. Groin puncture to reperfusion times did not differ between groups. For transferred patients, the delay within the intervention center was 5.0 minutes (95% CI, 0.5–9.6) longer. There was no significant difference in functional outcome between patients presenting during off- and on-hours (adjusted odds ratio, 0.92; 95% CI, 0.74–1.14). Reperfusion rates and complication rates were similar. Conclusions— Presentation during off-hours is associated with a slight delay in start of endovascular treatment in patients with acute ischemic stroke. This treatment delay did not translate into worse functional outcome or increased complication rates. </jats:sec

Prognostic Value of Thrombus Volume and Interaction With First-Line Endovascular Treatment Device Choice

BACKGROUND: A larger thrombus in patients with acute ischemic stroke might result in more complex endovascular treatment procedures, resulting in poorer patient outcomes. Current evidence on thrombus volume and length related to procedural and functional outcomes remains contradicting. This study aimed to assess the prognostic value of thrombus volume and thrombus length and whether this relationship differs between first-line stent retrievers and aspiration devices for endovascular treatment.METHODS: In this multicenter retrospective cohort study, 670 of 3279 patients from the MR CLEAN Registry (Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands) for endovascularly treated large vessel occlusions were included. Thrombus volume (0.1 mL) and length (0.1 mm) based on manual segmentations and measurements were related to reperfusion grade (expanded Treatment in Cerebral Infarction score) after endovascular treatment, the number of retrieval attempts, symptomatic intracranial hemorrhage, and a shift for functional outcome at 90 days measured with the reverted ordinal modified Rankin Scale (odds ratio &gt;1 implies a favorable outcome). Univariable and multivariable linear and logistic regression were used to report common odds ratios (cORs)/adjusted cOR and regression coefficients (B/aB) with 95% CIs. Furthermore, a multiplicative interaction term was used to analyze the relationship between first-line device choice, stent retrievers versus aspiration device, thrombus volume, and outcomes.RESULTS: Thrombus volume was associated with functional outcome (adjusted cOR, 0.83 [95% CI, 0.71-0.97]) and number of retrieval attempts (aB, 0.16 [95% CI, 0.16-0.28]) but not with the other outcome measures. Thrombus length was only associated with functional independence (adjusted cOR, 0.45 [95% CI, 0.24-0.85]). Patients with more voluminous thrombi had worse functional outcomes if endovascular treatment was based on first-line stent retrievers (interaction cOR, 0.67 [95% CI, 0.50-0.89]; P=0.005; adjusted cOR, 0.74 [95% CI, 0.55-1.0]; P=0.04). CONCLUSIONS: In this study, patients with a more voluminous thrombus required more endovascular thrombus retrieval attempts and had a worse functional outcome. Patients with a lengthier thrombus were less likely to achieve functional independence at 90 days. For more voluminous thrombi, first-line stent retrieval compared with first-line aspiration might be associated with worse functional outcome.</p

Combined Effect of Age and Baseline Alberta Stroke Program Early Computed Tomography Score on Post-Thrombectomy Clinical Outcomes in the MR CLEAN Registry

Background and Purpose: Ischemic brain tissue damage in patients with acute ischemic stroke, as measured by the Alberta Stroke Program Early CT Score (ASPECTS) may be more impactful in older than in younger patients, although this has not been studied. We aimed to investigate a possible interaction effect between age and ASPECTS on functional outcome in acute ischemic stroke patients undergoing endovascular treatment, and compared reperfusion benefit across age and ASPECTS subgroups. Methods: Patients with ischemic stroke from the MR CLEAN Registry (Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands; March 2014–November 2017) were included. Multivariable ordinal logistic regression was performed to obtain effect size estimates (adjusted common odds ratio) on functional outcome (modified Rankin Scale score) for continuous age and granular ASPECTS, with a 2-way multiplicative interaction term (age×ASPECTS). Outcomes in four patient subgroups based on age (&lt; versus ≥ median age [71.8 years]) and baseline ASPECTS (6–10 versus 0–5) were assessed. Results: We included 3279 patients. There was no interaction between age and ASPECTS on modified Rankin Scale ( P =0.925). The highest proportion of modified Rankin Scale 5 to 6 was observed in patients &gt;71.8 years with baseline ASPECTS 0 to 5 (68/107, 63.6%). There was benefit of reperfusion in all age-ASPECTS subgroups. Although the adjusted common odds ratio was lower in patients &gt;71.8 years with ASPECTS 0 to 5 (adjusted common odds ratio, 1.60 [95% CI, 0.66–3.88], n=110), there was no significant difference from the main effect ( P =0.299). Conclusions: Although the proportion of poor outcomes following endovascular treatment was highest in older patients with low baseline ASPECTS, outcomes did not significantly differ from the main effect. These results do not support withholding endovascular treatment based n a combination of high age and low ASPECTS. </jats:sec

Prognostic Value of Thrombus Volume and Interaction With First-Line Endovascular Treatment Device Choice

Background: A larger thrombus in patients with acute ischemic stroke might result in more complex endovascular treatment procedures, resulting in poorer patient outcomes. Current evidence on thrombus volume and length related to procedural and functional outcomes remains contradicting. This study aimed to assess the prognostic value of thrombus volume and thrombus length and whether this relationship differs between first-line stent retrievers and aspiration devices for endovascular treatment. Methods: In this multicenter retrospective cohort study, 670 of 3279 patients from the MR CLEAN Registry (Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands) for endovascularly treated large vessel occlusions were included. Thrombus volume (0.1 mL) and length (0.1 mm) based on manual segmentations and measurements were related to reperfusion grade (expanded Treatment in Cerebral Infarction score) after endovascular treatment, the number of retrieval attempts, symptomatic intracranial hemorrhage, and a shift for functional outcome at 90 days measured with the reverted ordinal modified Rankin Scale (odds ratio >1 implies a favorable outcome). Univariable and multivariable linear and logistic regression were used to report common odds ratios (cORs)/adjusted cOR and regression coefficients (B/aB) with 95% CIs. Furthermore, a multiplicative interaction term was used to analyze the relationship between first-line device choice, stent retrievers versus aspiration device, thrombus volume, and outcomes. Results: Thrombus volume was associated with functional outcome (adjusted cOR, 0.83 [95% CI, 0.71-0.97]) and number of retrieval attempts (aB, 0.16 [95% CI, 0.16-0.28]) but not with the other outcome measures. Thrombus length was only associated with functional independence (adjusted cOR, 0.45 [95% CI, 0.24-0.85]). Patients with more voluminous thrombi had worse functional outcomes if endovascular treatment was based on first-line stent retrievers (interaction cOR, 0.67 [95% CI, 0.50-0.89]; P=0.005; adjusted cOR, 0.74 [95% CI, 0.55-1.0]; P=0.04). Conclusions: In this study, patients with a more voluminous thrombus required more endovascular thrombus retrieval attempts and had a worse functional outcome. Patients with a lengthier thrombus were less likely to achieve functional independence at 90 days. For more voluminous thrombi, first-line stent retrieval compared with first-line aspiration might be associated with worse functional outcome

Effect of First‐Pass Reperfusion on Outcome After Endovascular Treatment for Ischemic Stroke

Background First‐pass reperfusion (FPR) is associated with favorable outcome after endovascular treatment. It is unknown whether this effect is independent of patient characteristics and whether FPR has better outcomes compared with excellent reperfusion (Expanded Thrombolysis in Cerebral Infarction [eTICI] 2C‐3) after multiple‐passes reperfusion. We aimed to evaluate the association between FPR and outcome with adjustment for patient, imaging, and treatment characteristics to single out the contribution of FPR. Methods and Results FPR was defined as eTICI 2C‐3 after 1 pass. Multivariable regression models were used to investigate characteristics associated with FPR and to investigate the effect of FPR on outcomes. We included 2686 patients of the MR CLEAN (Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands) Registry. Factors associated with FPR were as follows: history of hyperlipidemia (adjusted odds ratio [OR], 1.05; 95% CI, 1.01–1.10), middle cerebral artery versus intracranial carotid artery occlusion (adjusted OR, 1.11; 95% CI, 1.06–1.16), and aspiration versus stent thrombectomy (adjusted OR, 1.07; 95% CI, 1.03–1.11). Interventionist experience increased the likelihood of FPR (adjusted OR, 1.03 per 50 patients previously treated; 95% CI, 1.01–1.06). Adjusted for patient, imaging, and treatment characteristics, FPR remained associated with a better 24‐hour National Institutes of Health Stroke Scale (NIHSS) score (−37%; 95% CI, −43% to −31%) and a better modified Rankin Scale (mRS) score at 3 months (adjusted common OR, 2.16; 95% CI, 1.83–2.54) compared with no FPR (multiple‐passes reperfusion+no excellent reperfusion), and compared with multiple‐passes reperfusion alone (24‐hour NIHSS score, (−23%; 95% CI, −31% to −14%), and mRS score (adjusted common OR, 1.45; 95% CI, 1.19–1.78)). Conclusions FPR compared with multiple‐passes reperfusion is associated with favorable outcome, independently of patient, imaging, and treatment characteristics. Factors associated with FPR were the experience of the interventionist, history of hyperlipidemia, location of occluded artery, and use of an aspiration device compared with stent thrombectomy. </jats:sec

Clinical and Imaging Determinants of Collateral Status in Patients With Acute Ischemic Stroke in MR CLEAN Trial and Registry

Background and Purpose— Collateral circulation status at baseline is associated with functional outcome after ischemic stroke and effect of endovascular treatment. We aimed to identify clinical and imaging determinants that are associated with collateral grade on baseline computed tomography angiography in patients with acute ischemic stroke due to an anterior circulation large vessel occlusion. Methods— Patients included in the MR CLEAN trial (Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands; n=500) and MR CLEAN Registry (n=1488) were studied. Collateral status on baseline computed tomography angiography was scored from 0 (absent) to 3 (good). Multivariable ordinal logistic regression analyses were used to test the association of selected determinants with collateral status. Results— In total, 1988 patients were analyzed. Distribution of the collateral status was as follows: absent (7%, n=123), poor (32%, n=596), moderate (39%, n=735), and good (23%, n=422). Associations for a poor collateral status in a multivariable model existed for age (adjusted common odds ratio, 0.92 per 10 years [95% CI, 0.886–0.98]), male (adjusted common odds ratio, 0.64 [95% CI, 0.53–0.76]), blood glucose level (adjusted common odds ratio, 0.97 [95% CI, 0.95–1.00]), and occlusion of the intracranial segment of the internal carotid artery with occlusion of the terminus (adjusted common odds ratio 0.50 [95% CI, 0.41–0.61]). In contrast to previous studies, we did not find an association between cardiovascular risk factors and collateral status. Conclusions— Older age, male sex, high glucose levels, and intracranial internal carotid artery with occlusion of the terminus occlusions are associated with poor computed tomography angiography collateral grades in patients with acute ischemic stroke eligible for endovascular treatment. </jats:sec