A post hoc analysis of the TALOS-AMI trial found that body mass index may influence the clinical outcomes of de-escalating antiplatelet therapy from ticagrelor to clopidogrel in stabilized patients with acute myocardial infarction following percutaneous coronary intervention.
The findings, published in JAMA Network Open, indicated that patients with a body mass index (BMI) < 28 experienced a 46% reduction in adverse events with de-escalation, primarily as a result of fewer bleeding complications. However, no statistically significant benefit was observed in those with a BMI ≥ 28.
The TALOS-AMI trial, conducted across 32 centers in South Korea, originally enrolled 2,697 patients who had undergone percutaneous coronary intervention (PCI) for acute myocardial infarction (AMI). Following 1 month of dual therapy with aspirin and ticagrelor, 2,686 patients with available BMI data were randomly assigned to either continue ticagrelor (active control strategy) or switch to clopidogrel (de-escalation strategy) for an additional 11 months.
In patients with BMI < 28 (n = 2,344), de-escalation resulted in a significantly lower incidence of the composite primary endpoint—cardiovascular death, myocardial infarction, stroke, and Bleeding Academic Research Consortium (BARC) bleeding type 2, 3, or 5. This reduction was driven mainly by fewer bleeding events. No statistically significant differences in major adverse cardiovascular events (cardiovascular death, myocardial infarction, and stroke) were observed between the groups.
Conversely, in patients with BMI ≥ 28 (n = 342), the de-escalation strategy showed similar rates of adverse events compared with the active control strategy, suggesting that de-escalation provided no additional clinical advantage in this subgroup.
The researchers noted that lower BMI has been associated with higher bleeding risk in prior studies, possibly because of differences in drug metabolism, distribution volume, and platelet inhibition levels. Their findings aligned with previous research indicating that East Asian patients, who generally have lower BMIs, may be at increased risk of bleeding with potent P2Y12 inhibitors such as ticagrelor.
"Findings from this post hoc analysis of the TALOS-AMI study suggest that the outcomes associated with de-escalation strategies vary by BMI, with the greatest impact of de-escalation being seen in those with lower BMIs. The BMI threshold of 28 should be cautiously interpreted," the study authors concluded.
The study's limitations included its post hoc nature, reliance on baseline BMI without tracking changes over time, and a relatively small sample size for the BMI ≥ 28 subgroup. Additionally, the findings were drawn from a South Korean cohort, which may have limited generalizability to other populations.
The authors reported no competing interests.
