Figure 5.

Serum thromboxane (TX)B₂ levels at 24 h after aspirin intake (100 mg once daily) vs body mass index or body weight. Log-transformed serum TXB₂ levels measured 24 h after a witnessed aspirin intake are represented in relation to body mass index (panel A) and body weight (panel B). Triangles represent individual patients receiving aspirin for primary or secondary cardiovascular prevention, n = 71; circles represent individual healthy subjects, n = 25. Solid lines and green areas: predicted serum TXB₂ levels and 95% confidence intervals, respectively, as a function of increasing body mass index (panel A) and body weight (panel B) in the 96 study subjects. Horizontal dotted lines were drawn to indicate serum TXB₂ levels of 3, 6, and 9 ng/mL, corresponding to 99%, 98%, and 97% inhibition of platelet COX-1 activity, respectively, measured in healthy subjects. The vertical dotted lines were drawn to indicate on the abscissa scales the highest calculated values of body mass index (panel A) and body weight (panel B) compatible with these different levels of platelet COX-1 inhibition. Modified and redrawn from Petrucci et al., 2019, with permission from the publisher.