Applicable to Real-World Practice
A time-to-event analysis of the primary outcome showed that there were fewer outcomes in the first 30 days in the early DOAC initiation group, but the curves subsequently came together.
Subgroup analysis showed consistent results across all whole trial population, with no modification of the effect of early DOAC initiation according to stroke severity, reperfusion treatment, or previous anticoagulation.
Werring said that strengths of the OPTIMAS trial included a large sample size, a broad population with generalizability to real-world practice, and the inclusion of patients at higher bleeding risk than included in previous studies.
During the discussion, it was noted that the trial included few (about 3%) patients — about 3% — with very severe stroke (NIHSS score > 21), with the question of whether the findings could be applied to this group.
Werring noted that there was no evidence of heterogeneity, and if anything, patients with more severe strokes may have had a slightly greater benefit with early DOAC initiation. “So my feeling is probably these results do generalize to the more severe patients,” he said.
In a commentary accompanying The Lancet publication of the OPTIMAS trial, Else Charlotte Sandset, MD, University of Oslo, in Norway, and Diana Aguiar de Sousa, MD, Central Lisbon University Hospital Centre, Lisbon, Portugal, noted that the “increasing body of evidence strongly supports the message that initiating anticoagulation early for patients with ischaemic stroke is safe. The consistent absence of heterogeneity in safety outcomes suggests that the risk of symptomatic intracranial haemorrhage is not a major concern, even in patients with large infarcts.”
Regardless of the size of the treatment effect, initiating early anticoagulation makes sense when it can be done safely, as it helps prevent recurrent ischemic strokes and other embolic events. Early intervention reduces embolization risk, particularly in high-risk patients, and allows secondary prevention measures to begin while patients are still hospitalized, they added.
CATALYST Findings
The CATALYST meta-analysis included four trials, namely, TIMING, ELAN, OPTIMAS, and START, of early versus later DOAC administration in a total of 5411 patients with acute ischemic stroke and AF. In this meta-analysis, early was defined as within 4 days of stroke and later as 5 days or more.
The primary outcome was a composite of ischemic stroke, symptomatic, intracerebral hemorrhage, or unclassified stroke at 30 days. This was significantly reduced in the early group (2.12%) versus 3.02% in the later group, giving an odds ratio of 0.70 (95% CI, 0.50-0.98; P =.04).
The results were consistent across all subgroups, all suggesting an advantage for early DOAC.
Further analysis showed a clear benefit of early DOAC initiation in ischemic stroke with the curves separating early.
The rate of symptomatic intracerebral hemorrhage was low in both groups (0.45% in the early group and 0.40% in the later group) as was extracranial hemorrhage (0.45% vs 0.55%).
At 90 days, there were still lower event rates in the early group than the later one, but the difference was no longer statistically significant.
‘Practice Changing’ Results
Commenting on both studies, chair of the WSC session where the results of both OPTIMAS trial and the meta-analysis were presented, Craig Anderson, MD, The George Institute for Global Health, Sydney, Australia, described these latest results as “practice changing.”
“When to start anticoagulation in acute ischemic stroke patients with AF has been uncertain for a long time. The dogma has always been that we should wait. Over the years, we’ve become a little bit more confident, but now we’ve got good data from randomized trials showing that early initiation is safe, with the meta-analysis showing benefit,” he said.
“These new data from OPTIMAS will reassure clinicians that there’s no excessive harm and, more importantly, no excessive harm across all patient groups. And the meta-analysis clearly showed an upfront benefit of starting anticoagulation early. That’s a very convincing result,” he added.
Anderson cautioned that there still may be concerns about starting DOACs early in some groups, including Asian populations that have a higher bleeding risk (these trials included predominantly White patients) and people who are older or frail, who may have extensive small vessel disease.
During the discussion, several questions centered on the lack of imaging data available on the patients in the studies. Anderson said imaging data would help reassure clinicians on the safety of early anticoagulation in patients with large infarcts.
“Stroke clinicians make decisions on the basis of the patient and on the basis of the brain, and we only have the patient information at the moment. We don’t have information on the brain — that comes from imaging.”
Regardless, he believes these new data will lead to a shift in practice. “But maybe, it won’t be as dramatic as we would hope because I think some clinicians may still hesitate to apply these results to patients at high risk of bleeding. With imaging data from the studies that might change.”
The OPTIMAS trial was funded by University College London and the British Heart Foundation. Werring reported consulting fees from Novo Nordisk, National Institute for Health and Care Excellence, and Alnylam; payments or speaker honoraria from Novo Nordisk, Bayer, and AstraZeneca/Alexion; participation on a data safety monitoring board for the OXHARP trial; and participation as steering committee chair for the MACE-ICH and PLINTH trials. Åsberg received institutional research grants and lecture fees to her institution from AstraZeneca, Boehringer Ingelheim, Bristol Myers Squibb, and Institut Produits Synthése. Sandset and de Sousa were both steering committee members of the ELAN trial. Anderson reported grant funding from Penumbra and Takeda China.
A version of this article appeared on Medscape.com.