Correlation and categorical discrepancies of platelet function assays across diverse clinical settings: an exploratory analysis.

INTRODUCTION: Inconsistent results among platelet function assays complicate clinical interpretation. This study evaluated clinical agreement among light transmission aggregometry (LTA), thromboelastography (TEG)-platelet mapping, and the INNOVANCE Platelet Function Analyzer 200 system across diverse clinical settings. METHODS: Platelet function assays were performed in 3 cohorts, generating 4 datasets: 22 patients with aneurysm who were on dual antiplatelet therapy, 20 pregnant women on aspirin monotherapy, and 21 patients with an intracranial space-occupying lesion not on antiplatelet therapy allocated to a preoperative or postoperative cohort as appropriate. RESULTS: For the cyclooxygenase 1 pathway, no statistically significant correlations were found among any assay pairs in any dataset. For the adenosine diphosphate pathway, statistically significant correlations were observed only in dataset 1 between LTA and TEG (r = ‒0.80, 95% CI = ‒0.91 to ‒0.55; P < .001) and between PFA-200 and TEG (r = 0.44, 95%CI = 0.009 to 0.73; P = .04). In dataset 2, detection rates of aspirin responsiveness of PFA-200 (30%) were lower than with LTA (95%) and TEG (100%) (P < .001). In dataset 4, detection rates of platelet hyporesponsiveness (adenosine diphosphate pathway) were 61.9% (LTA), 100% (TEG), and 4.8% (PFA-200), with all pairwise comparisons statistically significantly different (P < .001). No statistically significant differences among assays were observed in other comparisons. DISCUSSION: No single assay can be recommended over the others. Assay selection should be guided by the specific clinical setting.