Reassuring information
Commenting on the research, J. David Spence, MD, professor of neurology at the Robarts Research Institute, London, Ont., who was not involved in the THALES trial, said this new analysis provided useful and important information that should reassure and encourage clinicians to use dual-antiplatelet therapy in this patient population.
He pointed out that the shift analysis gives the most clinically relevant results. “While the number of patients with a disabling stroke defined as an mRS greater than 1 is lower in the ticagrelor group, I am much more interested in the effect on more severe disability levels – those with an mRS score of 3 or more. Those are the disabilities that we really want to prevent. And from examining the shift analysis distribution, we can see that these more severe disabilities are being reduced with ticagrelor.”
Dr. Spence believes the benefit/risk ratio of dual-antiplatelet therapy could be further improved by better control of blood pressure. “The absolute risk of severe hemorrhage was low in this study, but in my view, most of this could have been prevented by better control of hypertension, as 20 of the 28 severe hemorrhages in the ticagrelor group were intracranial bleeds which can be significantly reduced by good blood pressure control.
“In my view, the increased risk of hemorrhage with dual-antiplatelet therapy should not be regarded as inevitable; it can be virtually eliminated with better medical care,” he stated.
Another outside commentator, Peter Rothwell, MD, PhD, professor of neurology, University of Oxford (England), also believes this is an important paper. “The main NEJM report presented the data on overall disability, but did not present a clear analysis of the effect of ticagrelor plus aspirin on disabling recurrent stroke, but disability in all patients is mainly determined by nonvascular premorbid disability and by the effects of the initial prerandomization stroke. It was highly unlikely that ticagrelor plus aspirin would change these pretrial factors. The only thing that treatment could change was the severity of any posttreatment recurrent stroke, which it did,” he said.
“There is evidence that aspirin plus clopidogrel has the same effect on disabling recurrent stroke. So we now know that ticagrelor plus aspirin also has this effect, which informs consideration of the relative merits of the two treatment strategies,” Dr. Rothwell added.
The THALES trial was sponsored by Astra Zeneca. Dr. Johnston reports support from Sanofi and AstraZeneca outside the submitted work. Dr. Amarenco reports grants and personal fees from AstraZeneca and Bristol-Myers Squibb during the conduct of the study.
A version of this article originally appeared on Medscape.com.