Reference intervals for platelet aggregation assessed by multiple electrode platelet aggregometry.
BACKGROUND
Analyses of platelet aggregation in hirudin whole blood using Multiplate® was validated. Reference intervals for the most commonly used agonists were established, and the association between platelet aggregation, age, gender and haematological values was analysed.


METHODS
We included 121 healthy individuals to establish reference intervals and six healthy individuals for evaluation of the day-to-day variation. Platelet aggregation was evaluated on hirudin whole blood employing Multiplate® induced by arachidonic acid, ADP, collagen and ristocetin (RISTOlow and RISTOhigh). Measurements of haematological values were performed employing Sysmex K-4500.


RESULTS
We found no association between platelet aggregation and age (p>0.57 for all agonists, except RISTOlow: p=0.05). Platelet aggregation was significantly higher in women compared to men for all agonists (p<0.0003), except RISTOlow (p=0.05). A reference interval is presented as 95% confidence interval suitable for any age and both sex. Day-to-day variation was <11% for all agonists except for RISTOlow. No association was found between platelet aggregation and haematocrit or red blood cell count after adjusting for age and gender except for RISTOhigh. A positive significant association was found between platelet count and platelet aggregation (p<0.04). Finally, a significant positive association was found between platelet aggregation and white blood cell count for all agonists (p<0.05) except RISTOlow and RISTOhigh (p>0.05).


CONCLUSIONS
Reference intervals for platelet aggregation in healthy individuals (age: 17 to 66 years) were established in hirudin whole blood measured by Multiplate® employing the most commonly used agonists.
Department of Clinical Biochemistry, Aarhus University Hospital, Denmark.
Peter
P
Rubak
Kirsten
K
Villadsen
Anne-Mette
AM
Hvas
D000293:Adolescent; D000328:Adult; D000368:Aged; D001792:Blood Platelets / Q000502:physiology*; D002478:Cells, Cultured; D003718:Denmark; D004566:Electrodes / Q000592:standards*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005260:Female; D006801:Humans; D008297:Male; D046228:Microarray Analysis / Q000295:instrumentation*; D008875:Middle Aged; D010974:Platelet Aggregation / Q000502:physiology*; D010979:Platelet Function Tests / Q000295:instrumentation* / Q000592:standards*; D012016:Reference Values; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D055815:Young Adult