Early versus late start of direct oral anticoagulants after acute ischaemic stroke linked to atrial fibrillation: an observational study and individual patient data pooled analysis

OBJECTIVE: The optimal timing to start direct oral anticoagulants (DOACs) after an acute ischaemic stroke (AIS) related to atrial fibrillation (AF) remains unclear. We aimed to compare early (≤5 days of AIS) versus late (>5 days of AIS) DOAC-start. METHODS: This is an individual patient data pooled analysis of eight prospective European and Japanese cohort studies. We included patients with AIS related to non-valvular AF where a DOAC was started within 30 days. Primary endpoints were 30-day rates of recurrent AIS and ICH. RESULTS: A total of 2550 patients were included. DOACs were started early in 1362 (53%) patients, late in 1188 (47%). During 212 patient-years, 37 patients had a recurrent AIS (1.5%), 16 (43%) before a DOAC was started; 6 patients (0.2%) had an ICH, all after DOAC-start. In the early DOAC-start group, 23 patients (1.7%) suffered from a recurrent AIS, while 2 patients (0.1%) had an ICH. In the late DOAC-start group, 14 patients (1.2%) suffered from a recurrent AIS; 4 patients (0.3%) suffered from ICH. In the propensity score-adjusted comparison of late versus early DOAC-start groups, there was no statistically significant difference in the hazard of recurrent AIS (aHR=1.2, 95% CI 0.5 to 2.9, p=0.69), ICH (aHR=6.0, 95% CI 0.6 to 56.3, p=0.12) or any stroke. CONCLUSIONS: Our results do not corroborate concerns that an early DOAC-start might excessively increase the risk of ICH. The sevenfold higher risk of recurrent AIS than ICH suggests that an early DOAC-start might be reasonable, supporting enrolment into randomised trials comparing an early versus late DOAC-start

Fatal Intracranial Hemorrhage Occurring after Oral Anticoagulant Treatment Initiation for Secondary Stroke Prevention in Patients with Atrial Fibrillation

BACKGROUND AND PURPOSE: In this pooled analysis of 7 multicenter cohorts we investigated potential differences in the incidence, characteristics and outcomes between intracranial hemorrhages (ICHs) associated with the use of non-vitamin K oral anticoagulants (NOAC-ICH) or vitamin K antagonists (VKA-ICH) in ischemic stroke (IS) patients after oral anticoagulant treatment initiation for atrial fibrillation (AF). METHODS: We included data from 4.912 eligible AF patients who were admitted in a stroke unit with IS or transient ischemic attack (TIA) and who were treated with either VKAs or NOACs within 3 months post-stroke. Fatal ICH was defined as death occurring during the first 30-days after ICH onset. We additionally performed a meta-analysis of available observational studies reporting 30-day mortality rates from NOAC-ICH or VKA-ICH onset. RESULTS: During 5970 patient-years of follow-up 71 participants had an ICH, of whom 20 were NOAC-ICH and 51 VKA-ICH. Patients in the two groups had comparable baseline characteristics, except for the higher prevalence of kidney disease in VKA-ICH patients. There was a non-significant higher number of fatal ICH in patients with VKA (11 events per 3,385 patient-years) than in those with NOAC (3 events per 2,623 patient-years; HR=0.32,95%CI:0.09-1.14). Three-month functional outcomes were similar (p>0.2) in the two groups. The meta-analysis showed a lower 30-day mortality risk for patients with NOAC-ICH compared to VKA-ICH (RR=0.70,95%CI:0.51-0.95). CONCLUSIONS: NOAC-ICH and VKA-ICH occurring during secondary stroke prevention of AF patients have comparable baseline characteristics and outcomes, except for the risk of fatal ICH within 30 days, which might be greater in VKA-ICH

Ischemic Stroke despite Oral Anticoagulant Therapy in Patients with Atrial Fibrillation

OBJECTIVE It is not known whether patients with atrial fibrillation (AF) with ischemic stroke despite oral anticoagulant therapy are at increased risk for further recurrent strokes or how ongoing secondary prevention should be managed. METHODS We conducted an individual patient data pooled analysis of 7 prospective cohort studies that recruited patients with AF and recent cerebral ischemia. We compared patients taking oral anticoagulants (vitamin K antagonists [VKA] or direct oral anticoagulants [DOAC]) prior to index event (OACprior) with those without prior oral anticoagulation (OACnaive). We further compared those who changed the type (ie, from VKA or DOAC, vice versa, or DOAC to DOAC) of anticoagulation (OACchanged) with those who continued the same anticoagulation as secondary prevention (OACunchanged). Time to recurrent acute ischemic stroke (AIS) was analyzed using multivariate competing risk Fine–Gray models to calculate hazard ratios (HRs) and 95% confidence intervals (CIs). RESULTS We included 5,413 patients (median age = 78 years [interquartile range (IQR) = 71–84 years]; 5,136 [96.7%] had ischemic stroke as the index event, median National Institutes of Health Stroke Scale on admission = 6 [IQR = 2–12]). The median CHA2DS2‐Vasc score (congestive heart failure, hypertension, age≥ 75 years, diabetes mellitus, stroke/transient ischemic attack, vascular disease, age 65–74 years, sex category) was 5 (IQR = 4–6) and was similar for OACprior (n = 1,195) and OACnaive (n = 4,119, p = 0.103). During 6,128 patient‐years of follow‐up, 289 patients had AIS (4.7% per year, 95% CI = 4.2–5.3%). OACprior was associated with an increased risk of AIS (HR = 1.6, 95% CI = 1.2–2.3, p = 0.005). OACchanged (n = 307) was not associated with decreased risk of AIS (HR = 1.2, 95% CI = 0.7–2.1, p = 0.415) compared with OACunchanged (n = 585). INTERPRETATION Patients with AF who have an ischemic stroke despite previous oral anticoagulation are at a higher risk for recurrent ischemic stroke despite a CHA2DS2‐Vasc score similar to those without prior oral anticoagulation. Better prevention strategies are needed for this high‐risk patient group. ANN NEUROL 202

Therapeutic potential of transdermal glyceryl trinitrate in the management of acute stroke

The nitric oxide donor, glyceryl trinitrate (GTN), is a candidate treatment for the management of acute stroke with haemodynamic and potential reperfusion and neuroprotective effects. When administered as a transdermal patch during the acute and subacute phases after stroke, GTN was safe, lowered blood pressure, maintained cerebral blood flow, and did not induce cerebral steal or alter functional outcome. However, when given within 6 h of stroke onset, GTN reduced death and dependency (odds ratio 0.52; 95% confidence interval 0.34–0.78), death, disability, cognitive impairment and mood disturbance, and improved quality of life (data from two trials, n = 312). In a pooled analysis of four studies (n = 186), GTN reduced between-visit systolic blood pressure variability over days 1–7 compared with no GTN (mean difference -2.09; 95% confidence interval -3.83 to -0.35; p = 0.019). The efficacy of GTN given in the ultra-acute/pre-hospital setting is currently being assessed and, if found to be beneficial, the implications for hyperacute stroke practice are significant. Here, we discuss the evidence to date, potential mechanisms of action and future possibilities, including unanswered questions, for the therapeutic potential of GTN in acute stroke

Oral Anticoagulants in the Oldest Old with Recent Stroke and Atrial Fibrillation

OBJECTIVE: To investigate the safety and effectiveness of direct oral anticoagulants (DOAC) versus vitamin-K-antagonists (VKA) after recent stroke in patients with atrial fibrillation (AF) aged ≥85 years. METHODS: Individual patient data analysis from 7 prospective stroke cohorts. We compared DOAC versus VKA treatment among patients with AF and recent stroke (<3 months) aged ≥85 versus <85 years. Primary outcome was the composite of recurrent stroke, intracranial hemorrhage (ICH) and all-cause death. We used simple, adjusted and weighted Cox regression to account for confounders. We calculated the net benefit of DOAC versus VKA by balancing stroke reduction against the weighted ICH risk. RESULTS: In total, 5,984 of 6,267 (95.5%) patients were eligible for analysis. Of those, 1,380 (23%) were aged ≥85 years and 3,688 (62%) received a DOAC. During 6,874 patient-years follow-up, the impact of anticoagulant type (DOAC versus VKA) on the hazard for the composite outcome did not differ between patients aged ≥85 (HR≥85y =0.65, 95%-CI [0.52, 0.81]) and <85 years (HR<85y =0.79, 95%-CI [0.66, 0.95]) in simple (pinteraction =0.129), adjusted (pinteraction =0.094) or weighted (pinteraction =0.512) models. Analyses on recurrent stroke, ICH and death separately were consistent with the primary analysis, as were sensitivity analyses using age dichotomized at 90 years and as a continuous variable. DOAC had a similar net clinical benefit in patients aged ≥85 (+1.73 to +2.66) and <85 years (+1.90 to +3.36 events/100 patient-years for ICH-weights 1.5 to 3.1). INTERPRETATION: The favorable profile of DOAC over VKA in patients with AF and recent stroke was maintained in the oldest old

Recurrent Ischemic Stroke and Bleeding in Patients With Atrial Fibrillation Who Suffered an Acute Stroke While on Treatment With Nonvitamin K Antagonist Oral Anticoagulants: The RENO-EXTEND Study

Background: In patients with atrial fibrillation who suffered an ischemic stroke while on treatment with nonvitamin K antagonist oral anticoagulants, rates and determinants of recurrent ischemic events and major bleedings remain uncertain. Methods: This prospective multicenter observational study aimed to estimate the rates of ischemic and bleeding events and their determinants in the follow-up of consecutive patients with atrial fibrillation who suffered an acute cerebrovascular ischemic event while on nonvitamin K antagonist oral anticoagulant treatment. Afterwards, we compared the estimated risks of ischemic and bleeding events between the patients in whom anticoagulant therapy was changed to those who continued the original treatment. Results: After a mean follow-up time of 15.0±10.9 months, 192 out of 1240 patients (15.5%) had 207 ischemic or bleeding events corresponding to an annual rate of 13.4%. Among the events, 111 were ischemic strokes, 15 systemic embolisms, 24 intracranial bleedings, and 57 major extracranial bleedings. Predictive factors of recurrent ischemic events (strokes and systemic embolisms) included CHA2DS2-VASc score after the index event (odds ratio [OR], 1.2 [95% CI, 1.0–1.3] for each point increase; P=0.05) and hypertension (OR, 2.3 [95% CI, 1.0–5.1]; P=0.04). Predictive factors of bleeding events (intracranial and major extracranial bleedings) included age (OR, 1.1 [95% CI, 1.0–1.2] for each year increase; P=0.002), history of major bleeding (OR, 6.9 [95% CI, 3.4–14.2]; P=0.0001) and the concomitant administration of an antiplatelet agent (OR, 2.8 [95% CI, 1.4–5.5]; P=0.003). Rates of ischemic and bleeding events were no different in patients who changed or not changed the original nonvitamin K antagonist oral anticoagulants treatment (OR, 1.2 [95% CI, 0.8–1.7]). Conclusions: Patients suffering a stroke despite being on nonvitamin K antagonist oral anticoagulant therapy are at high risk of recurrent ischemic stroke and bleeding. In these patients, further research is needed to improve secondary prevention by investigating the mechanisms of recurrent ischemic stroke and bleeding

Direct oral anticoagulants versus vitamin K antagonists after recent ischemic stroke in patients with atrial fibrillation

OBJECTIVE: We compared outcomes after treatment with direct oral anticoagulants (DOACs) and vitamin K antagonists (VKAs) in patients with atrial fibrillation (AF) and a recent cerebral ischemia. METHODS: We conducted an individual patient data analysis of seven prospective cohort studies. We included patients with AF and a recent cerebral ischemia (<3 months before starting oral anticoagulation) and a minimum follow-up of 3 months. We analyzed the association between type of anticoagulation (DOAC versus VKA) with the composite primary endpoint (recurrent ischemic stroke [AIS], intracerebral hemorrhage [ICH], or mortality) using mixed-effects Cox proportional hazards regression models; we calculated adjusted hazard ratios (HRs) with 95% confidence intervals (95% CIs). RESULTS: We included 4,912 patients (median age, 78 years [interquartile range {IQR}, 71-84]; 2,331 [47.5%] women; median National Institute of Health Stroke Severity Scale at onset, 5 [IQR, 2-12]); 2,256 (45.9%) patients received VKAs and 2,656 (54.1%) DOACs. Median time from index event to starting oral anticoagulation was 5 days (IQR, 2-14) for VKAs and 5 days (IQR, 2-11) for DOACs (p = 0.53). There were 262 acute ischemic strokes (AISs; 4.4%/year), 71 intracranial hemorrrhages (ICHs; 1.2%/year), and 439 deaths (7.4%/year) during the total follow-up of 5,970 patient-years. Compared to VKAs, DOAC treatment was associated with reduced risks of the composite endpoint (HR, 0.82; 95% CI, 0.67-1.00; p = 0.05) and ICH (HR, 0.42; 95% CI, 0.24-0.71; p < 0.01); we found no differences for the risk of recurrent AIS (HR, 0.91; 95% CI, 0.70-1.19; p = 0.5) and mortality (HR, 0.83; 95% CI, 0.68-1.03; p = 0.09). INTERPRETATION: DOAC treatment commenced early after recent cerebral ischemia related to AF was associated with reduced risk of poor clinical outcomes compared to VKA, mainly attributed to lower risks of ICH. ANN NEUROL 2019

Synthesis and characterization of soluble, blue-fluorescent polyamides and polyimides containing substituted p-terphenyl as well as long aliphatic segments in the main chain

A novel class of semiflexible polyamides and polyimides bearing substituted p-terphenyl as well as long aliphatic segments in the main chain were synthesized through pyrylium salts. Characterization of polymers was accomplished by inherent viscosity, elemental analysis, FT-IR, NMR, UV-vis luminescence spectroscopy, X-ray analysis, differential scanning calorimetry, thermomechanical analysis, thermogravimetric analysis, isothermal gravimetric analysis, and water uptake measurements. Polyamides displayed a degree of crystallinity and dissolved in polar aprotic solvents containing lithium chloride, as well as in trichloroacetic acid. Polyimides were amorphous and showed an excellent solubility, being soluble in various common solvents. The solutions of polyamides in DMF were blue-fluorescent with maxima at 362-370 nm. The emission maxims were not influenced appreciably upon the structure of the pendent groups and the length of the aliphatic spacers of backbone. The polymers possessed T(g)s at 98-131 degrees C and exhibited a satisfactory thermal stability. (C) 1999 John Wiley & Sons, Inc