The management of acute coronary syndrome (ACS) with antithrombotic medication achieves the desired goal of reducing the risk of future ischaemic events. However, these reductions are accompanied by increased risk of bleeding complications. A systematic review of the literature highlighted that there was a paucity of evidence on the incidence, timing, types, and predictors of these bleeding events, and their prognostic impact on mortality following hospital discharge after ACS. Using a UK national primary care consultation database with linkage to secondary care data and mortality data, the incidence, timing, types, and predictors of these bleeding events, and their association with all-cause mortality following hospital discharge post ACS were determined.
Among the 27,660 patients that fulfilled the inclusion/exclusion criteria for the study, 3,620 (13%) experienced first bleeding events at a median time of 123 days (IQR: 45 to 223) post-hospital discharge. The incidence of bleeding was 162/1000 person-years (95% CI: 157 to 167) within the first 12 months after discharge. Bleeding occurred more frequently in the first 30 days after discharge, with bruising (949 bleeds (26%)) and gastrointestinal bleed (705 bleeds, (20%)) the most common type of first bleeding events, while intracranial bleed was relatively rare (81 bleeds (2%)). Significant predictors of any post-discharge bleeding included prior history of bleeding complication, oral anticoagulant prescription, history of peripheral vascular disease, chronic obstructive pulmonary disease, and advanced age >80 years. Predictors for post-discharge bleeding varied depending on the severity and anatomic site of the bleeding event. Patients that experienced bleeding complications following hospital discharge for ACS had higher risk of mortality than those who did not (HR 1.70, 95% CI: 1.50, 1.92). This increased risk of mortality also varied by severity and anatomic site of the bleeding event, with intracranial bleed having the worst prognostic impact. This increased risk of mortality was more pronounced within the first 30 days following the bleeding event.
Patients who experienced bleeding complications following hospital discharge after ACS have distinct baseline characteristics. These characteristics can inform risk-benefit considerations in deciding on favourable combination and duration of secondary antithrombotic therapy. Further work is now required to combine these characteristics to develop and validate a risk score for bleeding complications following hospital discharge for use in the primary care setting.