The present study revealed that patients with a poor response to aspirin (study group) had a trend towards older age (64.8 year vs. 61.26 year, p = 0.049), were more likely to be female (60% vs.41.5%, p = 0.029), and were shorter in height (159.9 cm vs. 164.1 cm, p = 0.007) as compared to the patients with aspirin non-resistance (control group). These features are in agreement with the finding by Gum et al(23) . Age and weight may also reduce the bioavailability of low-dose aspirin, mainly due to increased inactivation of acetylsalicylic acid by gastrointestinal mucosal esterases and reduced absorption of active acetylsalicylic acid(24).