BACKGROUND: This individual participant data meta-analysis aimed to determine whether time to treatment influences the effect of intraarterial thrombolysis (IAT), intravenous thrombolysis, and conservative standard therapy on visual outcomes in nonarteritic central retinal artery occlusion. METHODS: We searched MEDLINE, CENTRAL, and Embase up to June 2023 for studies reporting treatment modality and peri-treatment best-corrected visual acuity (BCVA) for ≥5 participants, excluding patients with nonsevere vision loss (BCVA <1.0 logarithm of the minimum angle of resolution [logMAR]) or treated after 24 hours of symptom onset. The primary outcome was recovery from severe vision loss (final BCVA <1.0 logMAR). We used mixed-effect models and local polynomial regression to investigate nonlinear relationships between time to treatment and recovery from severe vision loss. RESULTS: Of 4074 screened studies, individual participant data were sought from 52, with 35 contributing individual participant data for 1038 participants. In total, 783 patients met inclusion criteria (age, 64.8±13.3 years; 35.5% female; baseline BCVA, 2.3±0.5 logMAR). For every hour decrease in time to treatment, thrombolysis was associated with greater improvement in BCVA (intraarterial, 0.02 logMAR [95% CI, 0–0.04]; intravenous, 0.04 logMAR [95% CI, 0.00–0.07]) than conservative standard therapy (0.01 logMAR [95% CI, 0–0.02]). A nonlinear relationship was detected for intraarterial thrombolysis with a changepoint at 8 hours (95% CI, 6.7–9.4). Thrombolysis was associated with increased recovery from severe vision loss compared with conservative standard therapy (intraarterial within 6 hours: odds ratio, 2.72 [95% CI, 1.02–7.28], 27.2% versus 12.0%; intravenous within 4.5 hours: odds ratio, 3.32 [95% CI, 1.24–8.92], 28.8% versus 11.1%). Findings were consistent in subgroup analysis restricted to patients receiving recombinant tissue-type plasminogen activator. Monte-Carlo simulations showed that a randomized controlled trial would require 95 participants per group to achieve 80% power to detect an odds ratio of 3.0 for recovery from severe vision loss. CONCLUSIONS: Early intervention in nonarteritic central retinal artery occlusion is associated with improvement in visual recovery, with intraarterial thrombolysis and intravenous thrombolysis outperforming nonthrombolytic treatments. These findings warrant confirmation in sufficiently powered randomized controlled trials.
Antithrombotic Treatment for Stroke Prevention in Cervical Artery Dissection: The STOP-CAD Study
BACKGROUND: Small, randomized trials of patients with cervical artery dissection showed conflicting results regarding optimal stroke prevention strategies. We aimed to compare outcomes in patients with cervical artery dissection treated with antiplatelets versus anticoagulation. METHODS: This is a multicenter observational retrospective international study (16 countries, 63 sites) that included patients with cervical artery dissection without major trauma. The exposure was antithrombotic treatment type (anticoagulation versus antiplatelets), and outcomes were subsequent ischemic stroke and major hemorrhage (intracranial or extracranial hemorrhage). We used adjusted Cox regression with inverse probability of treatment weighting to determine associations between anticoagulation and study outcomes within 30 and 180 days. The main analysis used an as-treated crossover approach and only included outcomes occurring with the above treatments. RESULTS: The study included 3636 patients (402 [11.1%] received exclusively anticoagulation and 2453 [67.5%] received exclusively antiplatelets). By day 180, there were 162 new ischemic strokes (4.4%) and 28 major hemorrhages (0.8%); 87.0% of ischemic strokes occurred by day 30. In adjusted Cox regression with inverse probability of treatment weighting, compared with antiplatelet therapy, anticoagulation was associated with a nonsignificantly lower risk of subsequent ischemic stroke by day 30 (adjusted hazard ratio [HR], 0.71 [95% CI, 0.45–1.12]; P =0.145) and by day 180 (adjusted HR, 0.80 [95% CI, 0.28–2.24]; P =0.670). Anticoagulation therapy was not associated with a higher risk of major hemorrhage by day 30 (adjusted HR, 1.39 [95% CI, 0.35–5.45]; P =0.637) but was by day 180 (adjusted HR, 5.56 [95% CI, 1.53–20.13]; P =0.009). In interaction analyses, patients with occlusive dissection had significantly lower ischemic stroke risk with anticoagulation (adjusted HR, 0.40 [95% CI, 0.18–0.88]; P interaction =0.009). CONCLUSIONS: Our study does not rule out the benefit of anticoagulation in reducing ischemic stroke risk, particularly in patients with occlusive dissection. If anticoagulation is chosen, it seems reasonable to switch to antiplatelet therapy before 180 days to lower the risk of major bleeding. Large prospective studies are needed to validate our findings.
Factors Associated With Stroke Recurrence After Initial Diagnosis of Cervical Artery Dissection
BACKGROUND: Patients presenting with cervical artery dissection (CAD) are at risk for subsequent ischemic events. We aimed to identify characteristics that are associated with increased risk of ischemic stroke after initial presentation of CAD and to evaluate the differential impact of anticoagulant versus antiplatelet therapy in these high-risk individuals. METHODS: This was a preplanned secondary analysis of the STOP-CAD study (Antithrombotic Treatment for Stroke Prevention in Cervical Artery Dissection), a multicenter international retrospective observational study (63 sites from 16 countries in North America, South America, Europe, Asia, and Africa) that included patients with CAD predominantly between January 2015 and June 2022. The primary outcome was subsequent ischemic stroke by day 180 after diagnosis. Clinical and imaging variables were compared between those with versus without subsequent ischemic stroke. Significant factors associated with subsequent stroke risk were identified using stepwise Cox regression. Associations between subsequent ischemic stroke risk and antithrombotic therapy type (anticoagulation versus antiplatelets) among patients with identified risk factors were explored using adjusted Cox regression. RESULTS: In all, 4023 patients (mean age was 47.4 years; 44.5% were women) were included. By day 180, subsequent ischemic stroke occurred in 5.3% of the cohort. In adjusted Cox regression, factors associated with increased risk of subsequent ischemic stroke were prior history of ischemic stroke (adjusted hazard ratio [aHR], 7.31 [95% CI, 1.61–33.13]; P =0.010), presentation within 7 days from first symptoms (aHR, 3.04 [95% CI, 1.04–8.91]; P =0.043), infarct on baseline imaging (aHR, 9.85 [95% CI, 3.65–26.58]; P <0.001), and occlusive dissection (aHR, 2.34 [95% CI, 1.03–5.34]; P =0.043). Only patients with occlusive dissection demonstrated a reduced risk of subsequent ischemic stroke when treated with anticoagulation versus antiplatelets (aHR, 0.36 [95% CI, 0.16–0.80]; P =0.01). CONCLUSIONS: In this post hoc analysis of the STOP-CAD study, several factors associated with subsequent ischemic stroke were identified among patients with CAD. Furthermore, we identified a potential benefit of anticoagulation in patients with CAD with occlusive dissection. These findings require validation by meta-analyses of prior studies to formulate optimal treatment strategies for specific high-risk CAD subgroups.