Comparative Study Of Bleeding Complications Related To The Use Of Antithrombotic Agents

Objective: To assess the risk of bleeding complication and the types of bleedingcomplications due to the associated use of aspirin with clopidogrel (dual antiplatelettherapy), each of the drug used alone and warfarin used alone based on FDASpontaneous Reporting System and Adverse Events Reporting System (SRS/AERS)database.Methods: After excluding duplicated records, the reports were divided into referencegroup as no aspirin, clopidogrel or warfarin and four index groups involving aspirin orclopidogrel alone, and associated use of aspirin with clopidogre and warfarin alonegroups, and define haemorrhages-related adverse events (HRAEs) according to438preferred terms terms (PTs) belongs to the haemorrhages Standard MedDRA Queries(SMQs) from Medical Dictionary for Regulatory Activities. Descriptive statistics,logistic regression and adverse drug reaction (ADR) odds ratios were performedonestimating the risk for these four scenarios and differences of the HRAE typesbetween them.Results: The age and gender of patients, the reporting countries and sources of reportsare significant difference for these four scenarios. The incidence rate of HRAEs forthe index groups is warfarin (30.96%), aspirin/clopidogrel (22.36%), clopidogrel(16.13%) and aspirin (13.73%). The gastrointestinal system HRAEs were the mostfrequently reported HRAEs for aspirin alone (4.82%), clopidogrel alone (5.17%) andaspirin/clopidogrel groups (8.26%), and the investigations HRAEs were the mostfrequently reported HRAEs for warfarin alone. The risk of HRAEs increase as ageincreases for all the groups. For aspirin alone, there is no significant differencebetween the different genders for risk of HRAEs (P>0.05). For clopidogrel alone andaspirin/clopidogrel groups the risk of HRAEs with female is higher than male(P<0.05), and for warfarin the risk of HRAEs with male is higher than female(P<0.05). Referring to the distribution of system organ class for HRAEs,gastrointestinal system; investigations, injury, poisoning and proceduralcomplications; vascular disorders; nervous system disorders; respiratory, thoracic andmediastinal system HRAEs are the most reported for all the groups, but the frequencyof HRAEs for different system organ classes are much different for the five scenarios.Referring to the distribution of different HRAEs, international normalised ratio increased, haemoglobin decreased, gastrointestinal haemorrhage, haemorrhage,contusion, epistaxis, rectal haemorrhage, haematocrit decreased, haematuria are themost reported, and the frequency of these HRAEs are also much different for thedifferent scenarios. For all groups, the distribution of HAREs between the differentgenders is not much blance.Conclusions: The risk of HRAEs with the associated aspirin/clopidogrel use is higherthan aspirin or clopidogrel used alone but lower than warfarin used alone in theclinical use. And the distribution of bleeding complications, the risk of HRAEsbetween difference age groups and difference genders are much different betweendifferent groups.