Acute coronary syndrome: bleeding, platelets and gender

BACKGROUND Bleeding complications increase mortality in patients with acute coronary syndrome (ACS). Potential gender difference in bleeding regarding prevalence, location, severity and prognostic impact is still controversial and not well investigated. In regard to this aspect the relevance of triple antithrombotic therapy (TAT) is questioned. There is an ongoing debate on the clinical implications of TAT and furthermore assumed that bleeding complications, except impact on outcome, also are associated with great influence on health economy. The main focus of this thesis was to further investigate the incidence and impact of bleeding complications in patients treated for ACS, with special reference to gender disparities, TAT and health economics. The thesis will highlight the importance of improved bleeding prevention strategies for both men and women. METHOD Paper I, II and III Observational studies from the SWEDEHEART register. In paper I we investigated patients hospitalised with myocardial infarction (MI) during 2006–2008. Outcomes were in-hospital bleedings, in-hospital mortality and one-year mortality in hospital survivors. In paper II, all patients with MI, in the County of Östergötland, Sweden during 2010 were included and followed for one year. The patients' medical records were evaluated, in relation to short and long-term bleeding complications, bleeding location, withdrawal of platelet inhibiting drugs and nonfatal MI and death. Paper III included all patients discharged with (TAT) in the County of Östergötland 2009-2015. Information about bleeds and ischemic complications during one-year follow-up were retrieved from the medical records. Estimation of the health care costs associated with bleeding episodes were added to the evaluation. Paper IV Patients with MI, scheduled for coronary angiography were recruited. All patients received clopidogrel and aspirin. A subgroup of patients received GP IIb/IIIa-inhibitor. Outcomes were platelet aggregation assessed at several time points, using a Multiplate impedance aggregometer, measurement of P-selectin in plasma, evaluation of high residual platelet reactivity (HRPR) and low residual platelet reactivity (LRPR) respectively and incidence of bleeding complications. A comparison between women and men was performed. RESULTS Paper I A total number of 50.399 patients were included, 36.6% women. In-hospital bleedings were more common in women (1.9% vs. 3.1%, p<0.001) even after multivariable adjustment