Sex differences in the expression of haemorheological determinants in individuals with atherothrombotic risk factors and in apparently healthy people.

BACKGROUND Increased red cell aggregation can be detrimental, leading to slow capillary blood flow and tissue hypoxaemia. Sex differences in the degree of erythrocyte adhesiveness/aggregation in the peripheral blood have not been clearly shown. OBJECTIVES To determine whether there are sex differences in the expression of erythrocyte adhesiveness/aggregation in the peripheral blood in individuals with atherothrombotic risk factors and in apparently healthy people. METHODS From a cohort of 965 participants in the Tel Aviv Medical Centre inflammation survey, 192 pairs of different sex were matched for age, body mass index, hip and waist circumferences, cardiovascular risk factors, and the intake of active cardiovascular drugs. RESULTS Women had an enhanced degree of red cell aggregation (p < 0.0005) as well as increased concentrations of inflammation sensitive proteins including fibrinogen and C reactive protein. Women had a lower haemoglobin concentration than men, but this did not affect the degree of erythrocyte adhesiveness/aggregation. CONCLUSIONS The significant increase in red blood cell adhesiveness/aggregation in the peripheral blood of women with atherothrombosis could be relevant to the more eventful course that some women experience during and following acute ischaemic disease.