PLATELET-ADHESION IN PATIENTS PRONE TO ARTERIAL AND VENOUS THROMBOSIS- THE IMPACT OF GENDER, SMOKING AND HEREDITY

Platelet adhesion was measured in 271 consecutive subjects (151F, 120M ) referred to the department for investigation of their propensity to develop thrombosis. Arterial thrombosis was the cause in 27% of the su bjects and pulmonary embolism in 23%, whereas venous thrombosis was th e cause in 50%. Ninetythree patients were using nicotine in the form o f smoking or snuffing, 45 were ex-users and 130 patients never-users. Adhesion was measured as the retention of platelets in a commercially available column of glass beads. After strict standardization of the m ethod the reproducibilities within-day and between-day were good. Plat elet retention was increased in thrombosis-prone patients as compared to references (p=0.016). This increase was seen irrespective of type o f thrombosis. Multifactor ANOVA analysis revealed a strong dependence of gender and smoking habits with higher platelet retention in men and in ex-smokers and current smokers. The highest levels were found in e x-smokers with arterial thrombosis and in current smokers with pulmona ry embolism. In the control population we found high platelet retentio n in smokers (p=0.001) and in those with a family history of thrombosi s (p=0.0025). It is concluded that the measurement of platelet retenti on may form a basis for the selection of patients to antiplatelet ther apy and that the activity of platelets is affected by smoking and rela ted to sex and family history of thrombosis. It is also concluded that thrombus formation in men and women may be goverened partly by differ ent mechanisms.