Increased body weight appears to be associated with decreased response to aspirin 100 mg once a day among those with coronary artery disease, underscoring the importance of tailoring aspirin dosage to body weight. This research was presented at the American College of Cardiology 68th Annual Scientific Session & Expo, held March 16-18, 2019, in New Orleans, Louisiana.

This study included 2 datasets, the first of which included 368 participants (164 of whom were outpatients with stable coronary artery disease and 204 of whom were hospitalized for acute coronary syndrome) and the second of which included 70 participants (all of whom had stable coronary artery disease). All participants took 100 mg of plain aspirin daily.

Related Articles

Using the VerifyNow Aspirin assay (in Aspirin Reaction Units [ARU], the first dataset underwent assessment for arachidonic acid and platelet aggregability. Those with acute coronary syndromes underwent platelet aggregability assessment upon discharge. Among those in the second dataset, assessments of serum thromboxane B2 dosage were performed using an ELISA assay (pg/mL). Statistical analysis was performed using logistic and stepwise linear regression models with adjustments for possible confounders.

Among those in the first dataset, there was an independent correlation between platelet aggregability with VerifyNow and higher body weight (P =.012), with an 8.41 ARU (95% CI, 1.86-14.97) increase per additional 10 kg. There was also a significant correlation between aspirin nonresponse (ARU ≥550) with higher body weight (P =.007), with each additional 10 kg corresponding to an odds ratio of 1.23 (95% CI, 1.06-1.42).

Body mass index also showed a significant correlation with nonresponse, with a 15.5 ARU (95% CI, 5.0-25.9) increase and an odds ratio of 1.43 (95% CI, 1.13-1.81;P =.003) corresponding to each 5 kg/m2 increase. The second dataset showed significantly elevated serum thromboxane B2 associated with weight more than 70 kg (222.6±62.9 vs 194.9±61.9 pg/mL; P =.018).

Researchers conclude that in “two different cohorts of patients with [coronary artery disease] on plain aspirin 100 mg QD, increased bodyweight was independently associated with impaired response to aspirin….results reinforce the need to tailor aspirin dose according to bodyweight in order to avoid ischemic events.”


Furtado RHM, Arantes F, Barbosa C, et al. Increased bodyweight and inadequate response to aspirin in individuals with coronary artery disease. Presented at: American College of Cardiology 68th Annual Scientific Session & Expo; March 16-18, 2019; New Orleans, LA. Abstract 1129-360.