Association of platelet aggregation with lipid levels in the Japanese population: the Suita study

Platelets play a pivotal role in atherothrombotic diseases. Platelet aggregability induced by agonists has great interindividual variability; however, the factors influencing platelet aggregability variation have not been characterized in Asia.

To examine the confounding factors influencing platelet counts and responsiveness to agonists, we measured the platelet counts and platelet aggregability induced by 1.7 µM adenosine diphosphate (ADP) or 1.7 µg/mL collagen using a light transmittance aggregometer in the Japanese general population without medication or cardiovascular disease (387 men and 550 women) in the Suita Study.

Platelet counts were negatively correlated with age in both men and women (Spearman's rank correlation coefficient: r(s)=-0.230 and -0.227; p< 0.01, respectively). In women, platelet counts were correlated negatively with the high-density lipoprotein (HDL) cholesterol level and positively with the low-density lipoprotein (LDL) cholesterol/HDL cholesterol (L/H) ratio (r(s)=-0.135 and 0.119; p< 0.01, respectively). In women, platelet aggregabilities by ADP and collagen were correlated with age (r(s)=0.118 and 0.143; p< 0.01, respectively), and collagen-induced platelet aggregability was correlated with the LDL cholesterol level, the L/H ratio, and the non-HDL cholesterol level (r(s)=0.167, 0.172, and 0.185; p< 0.01, respectively). Even after adjustment for age, systolic blood pressure, body mass index, and current smoking and drinking, the association of platelet counts with the L/H ratio in women and associations of collagen-induced platelet aggregability with the L/H ratio and the non-HDL cholesterol level remained.

Examination of platelet counts and platelet aggregability induced by ADP and collagen revealed gender, age and lipid levels as factors influencing inter-individual variability.