Table 3. Blood platelet activation and reactivity characteristics of subjects with lower and higher ‘cumulative reactivity’ of blood platelets.
| Parameter |
Individuals with lower ‘cumulative blood platelet reactivity’ (n= 77) |
Individuals with higher ‘cumulative blood platelet reactivity’ (n= 78) |
|
platelet activation (in circulating/resting platelets) |
||
| P-selectinresting plt (%) | 2.5 (1.4 – 4.6) | 2.3 (1.6 – 4.7) |
| GPIIb/IIIa resting plt (%) | 1.7 (0.8 – 3.1) | 2.2 (1.1 – 4.0) |
| ‘cumulative platelet activation’ | -1.0 (-5.2 – 0.7) | 0.3 (-1.6 – 1.7)U* |
|
platelet reactivity (in vitro response to agonists) |
||
| Amax, arachidonate [a.u.] | 104.1 (78.0 – 121.5) | 142.4 (131.0 – 157.6) U††† |
| Amax, collagen [a.u.] | 123.6 (93.9 – 140.0) | 173.3 (157.9 – 191.0) U††† |
| Amax, ADP [a.u.] | 97.1 ± 22.9 | 139.5 ± 20.6 T††† |
| ‘cumulative blood platelet reactivity’ | -1.9 (-2.8 - -1.0) | 1.8 (1.0 – 3.5) U††† |
| P-selectinarachidonate [%] | 44.3 (31.3 – 62.5) | 46.9 (31.2 – 62.4) U# |
| P-selectincollagen [%] | 45.8 (28.1 – 66.5) | 47.7 (30.1 – 59.5) |
| GPIIb/IIIa arachidonate [%] | 43.5 (26.2 – 60.0) | 46.3 (35.3 – 61.2) U# |
| GPIIb/IIIacollagen [%] | 51.2 (40.3 – 57.7) | 49.6 (36.8 – 68.4) U# |
| ‘cumulative P-selectin expression’ |
-0.4 (-1.2 – 0.1) | 0.2 (-0.9 – 1.2) U# |
| ‘cumulative GPIIb/IIIa expression’ |
-0.8 (-2.4 – 0.5) | 0.4 (-1.2 – 1.3) U# |
Variables, adjusted for age and sex, are presented as means ± SD or medians with interquartile ranges. The individuals with ‘lower’ or ‘higher blood platelet reactivity’, were identified according to the dichotomised values of the van der Waerden normal scores of Amax cumulated through the agonists used (AA, collagen, ADP), referred to as ‘cumulative blood platelet reactivity’. The values of the van der Waerden normal scores of the expressions of surface membrane antigens in circulating resting platelets cumulated through the antigens (P-selectin or the active GPIIb/IIIa) are referred to as ‘cumulative platelet activation’ and the van der Waerden normal scores of platelet response to agonists cumulated through the agonists used (AA, collagen) are referred to as ‘cumulative P-selectin/GPIIb/IIIa expression’ (see details in Materials and methods and Results).
Comparisons between the groups were performed on the Box-Cox-transformed adjusted values with the use of the covariance analysis (ANCOVA): *P≤ 0.05; #P< 0.01; †P< 0.005; ††P< 0.001; †††P<< 0.0001.
Abbreviations used: ADP, adenosine diphosphate; Amax, maximal aggregation of blood platelets; GPIIb/IIIa, the glycoprotein complex in platelet surface membranes, the receptor for fibrinogen.