Thrombosis Research · Nov 2026
Distinct age- and sex-specific patterns of basal platelet reactivity: A repeated multi-agonist study in healthy Korean adults
By Kim HS, Kim GY, Shin JG
Baseline platelet reactivity varies by sex, age, and activation pathway, yet pathway-resolved, drug-free, sex- and age-stratified reference data remain limited. We aimed to explore the sex- and age-specific reference data and those effects on baseline platelet reactivity in healthy, drug-free adults using a multi-pathway assessment. We established reference data for basal platelet aggregation in a balanced cohort of 121 healthy Korean adults (57 male and 64 female participants; 20s–≥70s). Platelet aggregation induced by adenosine diphosphate (ADP), arachidonic acid (AA), thrombin receptor–activating peptide-6 (TRAP), collagen (COL), and ristocetin (RISTO) was measured twice at an interval of at least one week using a standardized whole-blood impedance method. Inter- and intra-individual variability accounted for approximately 87–90% and 10–13% of total variance, respectively. Among the agonists, a significant sex difference was observed only for TRAP-induced aggregation, which was higher in males than females. Age-related patterns differed between sexes: in males, aggregation peaked in the 40s then declined (inverted U-shape, statistically significant for ADP, p < 0.05); in females, aggregation decreased until the 50s, increased in the 60s, and dropped sharply in the over-70s, with statistical significance for AA and COL (p < 0.05). TRAP- and COL-induced platelet aggregation was higher in smokers than non-smokers. This study provides the first evidence revealing distinct age-specific patterns in males and females in basal platelet aggregation under multi-pathway assessment, although confirmation in larger and more diverse cohorts is warranted.