Table 4.
Least squares (LS) mean change from baseline to day 12 in platelet reactivity assays in healthy subjects and patients with sickle cell disease
| Change from baseline [LS mean (SEM)] | Sickle cell disease – Healthy [LS mean (95% CI)] | P value* | ||
|---|---|---|---|---|
| Healthy subjects (n = 13) | Sickle cell disease (n = 13) | |||
| LTA/MPA, 5 μm ADP (%) | −48.55 (5.11) | −32.27 (6.33) | 16.28 (−1.49, 34.05) | 0.070 |
| LTA/MPA, 20 μm ADP (%) | −41.89 (5.28) | −31.82 (5.55) | 10.07 (−6.62, 26.77) | 0.219 |
| VerifyNow (PRU) | −231.00 (25.28) | −148.17 (28.31) | 82.83 (−6.23, 171.88) | 0.066 |
| VerifyNow, device-reported inhibition (%) | 59.97 (5.78) | 40.89 (6.29) | −19.08 (−39.07, 0.92) | 0.060 |
| VerifyNow, calculated inhibition (%) | 62.52 (6.93) | 43.85 (7.76) | −18.67 (−43.07, 5.72) | 0.124 |
| MEA, 6.5 mm ADP (AU.min) | −58.60 (6.49) | −48.79 (7.31) | 9.81 (−13.83, 33.46) | 0.396 |
| MEA, 20 mm ADP (AU.min) | −63.88 (6.61) | −52.01 (7.39) | 11.87 (−10.85, 34.59) | 0.288 |
| Plateletworks, 20 μm ADP (%) | −42.35 (6.84) | −61.21 (7.04) | −18.86 (−40.50, 2.78) | 0.083 |
| VASP, flow cytometry (PRI%) | −40.69 (5.76) | −58.52 (7.16) | −17.83 (−38.53, 2.88) | 0.086 |
| VASP, ELISA (PRI%) | −67.34 (4.77) | −64.44 (4.54) | 2.90 (−11.57, 17.38) | 0.679 |
Abbreviations are as follows: ADP, adenosine diphosphate; AU.min, area under the aggregation curve; ELISA, enzyme-linked immunosorbent assay; LTA, light transmission aggregometry; MEA, multielectrode aggregometry; MPA, maximal platelet aggregation; PRI, platelet reactivity index; PRU, P2Y12 reaction units; and VASP, vasodilator-stimulated phosphoprotein.
*
P values are from an analysis of covariance model, with dose, baseline measurement, subject group, and dose-by-subject group interaction as fixed effects.