Table 4

Contribution to on-treatment platelet reactivity

5 μmol/L ADP-induced LTA*20 μmol/L ADP-induced LTA†PlateletWorks‡VerifyNow P2Y12 assay§
βadj (95% CI), % aggregationp Valueβadj (95% CI), % aggregationp Valueβadj (95% CI), % aggregationp Valueβadj (95% CI), PRUp Value
CYP2C19*25.93 (4.03 to 7.83)<0.0016.55 (4.66 to 8.44)<0.00110.48 (4.89 to 16.07)<0.00125.30 (15.88 to 34.73)<0.001
Age (10 years)1.91 (0.90 to 2.92)<0.0010.82 (−0.18 to 1.83)0.1081.21 (−1.77 to 4.19)0.42410.77 (5.76 to 15.78)<0.001
BMI (kg/m2)0.36 (0.10 to 0.61)0.0060.61 (0.36 to 0.86)<0.0010.64 (−0.15 to 1.44)0.1142.61 (1.36 to 3.85)<0.001
Male gender−3.01 (−5.39 to −0.62)0.014−2.91 (−5.28 to −0.53)0.016−1.43 (−8.62 to 5.75)0.695−33.04 (−44.82 to −21.26)<0.001
Current smoking−0.38 (−2.18 to 1.43)0.683−0.64 (−2.44 to 1.15)0.4812.20 (−2.67 to 7.07)0.3740.48 (−8.46 to 9.42)0.916
Hypertension0.14 (−2.25 to 2.53)0.908−0.08 (−2.46 to 2.30)0.9492.49 (−4.36 to 9.33)0.476−0.74 (−12.53 to 11.05)0.902
Diabetes mellitus2.12 (−0.46 to 4.70)0.1072.90 (0.34 to 5.46)0.0272.79 (−4.83 to 10.41)0.47217.66 (4.98 to 30.35)0.006
LVEF <45%1.12 (−1.64 to 3.88)0.4252.42 (−0.34 to 5.17)0.085−2.24 (−10.05 to 5.56)0.5727.12 (−6.44 to 20.69)0.303
Renal failure0.62 (−3.17 to 4.40)0.750−0.25 (−4.02 to 3.52)0.896−8.20 (−18.92 to 2.52)0.133−4.98 (−23.82 to 13.86)0.604
Clopidogrel LD3.25 (1.48 to 5.01)<0.0013.66 (1.91 to 5.42)<0.0012.61 (−2.57 to 7.79)0.32319.04 (10.32 to 27.75)<0.001
PPI0.89 (−1.43 to 3.20)0.4521.31 (−0.99 to 3.61)0.264−2.48 (−9.51 to 4.55)0.48820.08 (8.66 to 31.50)0.001
Amlodipine3.29 (0.85 to 5.72)0.0084.21 (1.78 to 6.64)0.001−0.21 (−7.17 to 6.74)0.95218.55 (6.48 to 30.62)0.003
PLT (109/l)0.01 (0.00 to 0.03)0.0350.01 (−0.01 to 0.02)0.3280.00 (−0.04 to 0.03)0.938−0.09 (−0.16 to −0.03)0.004
MPV (fl)−0.13 (−1.30 to 1.04)0.8220.40 (−0.76 to 1.57)0.5000.01 (−3.57 to 3.60)0.9934.84 (−0.90 to 10.58)0.098
  • Adjusted β coefficients with corresponding 95% CIs (βadj (95% CI)) for on-treatment platelet reactivity, in a multivariate linear regression model containing CYP2C19*2 carrier status (*1/*1, *1/*2 or *2/*2) in addition to clinical characteristics that were associated with on-treatment platelet reactivity in univariate analysis (p<0.10).

  • Unadjusted β for CYP2C19*2 carrier status *6.30 (4.59–8.01); †7.01 (5.32–8.71); ‡12.23 (7.28–17.19) and §28.21 (19.35–37.07) p<0.001 for all.

  • Amlodipine was shown to be the calcium channel blocker associated with HPR in a previously published sub-analysis of POPular.5

  • BMI, body mass index; LD, loading dose either 300 mg or 600 mg clopidogrel; LTA, light transmittance aggregometry; LVEF, left ventricular ejection fraction; MPV, mean platelet volume; PLT, platelet count; PPI, proton pump inhibitor; PRU, P2Y12 reaction units.