Crude and adjusted HRs for association of antiplatelet prescription (AC vs AP and AC vs AT) with bleeding and ischaemic events and mortality in ACS and STEMI-only patients (2012–2017)
| ACS | STEMI | ||||||||
| Number of bleeds | Number of bleeds | ||||||||
| All n=4689 | AC n=2769 | AT n=1920 | HR (95% CI) (AC vs AT) | All n=2587 | AC n=1023 | AP n=406 | AT n=1158 | HR (95% CI) (AP vs AC and AT vs AC) | |
| Primary outcome (any bleeding) | |||||||||
| Unadjusted; n (%) | 416 (8.9%) | 209 (7.5%) | 207 (10.8%) | 1.48 (1.22 to 1.80) | 260 (10.1%) | 80 (7.8%) | 46 (11.3%) | 134 (11.6%) | AP: 1.48 (1.02 to 2.12) AT: 1.53 (1.16 to 2.01) |
| Adjusted | 1.47 (1.19 to 1.82) | AP: 1.77 (1.21 to 2.59)11 AT: 1.50 (1.10 to 2.05)11 | |||||||
| Secondary outcomes (adjusted) | |||||||||
| Major bleeding (HES-recorded); n (%) | 117 (2.5%) | 63 (2.3%) | 54 (2.8%) | 1.33 (0.89 to 1.99) | 70 (2.7%) | 22 (2.2%) | 9 (2.2%) | 39 (3.4%) | AP: 1.26 (0.56 to 2.87)12 AT: 1.99 (1.11 to 3.57)12 |
| Minor bleeding (CPRD-recorded); n (%) | 332 (7.1%) | 161 (5.8%) | 171 (8.9%) | 1.60 (1.26 to 2.03) | 208 (8.0%) | 62 (6.1%) | 39 (9.6%) | 107 (9.2%) | AP: 1.90 (1.26 to 2.88)13 AT: 1.53 (1.09 to 2.15)13 |
| All-cause mortality; n (%) | 104 (2.2%) | 70 (2.5%) | 34 (1.8%) | 0.94 (0.60 to 1.47) | 60 (2.3%) | 31 (3.0%) | 7 (1.7%) | 22 (1.9%) | AP: 1.30 (0.54 to 3.17)14 AT: 0.92 (0.51 to 1.67)14 |
| Cardiovascular mortality; n (%) | 48 (1.0%) | 32 (1.2%) | 16 (0.8%) | 0.92 (0.48 to 1.78) | 27 (1.0%) | 15 (1.5%) | 4 (1.0%) | 8 (0.7%) | AP: 1.48 (0.45 to 4.87)15 AT: 0.60 (0.24 to 1.52)15 |
| Mortality from bleeding; n (%) | 7 (0.1%) | 6 (0.2%) | 1 (0.1%) | 0.33 (0.04 to 2.86) | 6 (0.2%) | 4 (0.4%) | 2 (0.5%) | 0 | AP: 2.64 (0.32 to 21.86)16 AT: -- |
| MI; n (%) | 133 (2.8%) | 85 (3.1%) | 48 (2.5%) | 0.91 (0.61 to 1.34) | 72 (2.8%) | 27 (2.6%) | 12 (3.0%) | 33 (2.8%) | AP: 1.20 (0.60 to 2.42)17 AT: 1.22 (0.69 to 2.14)17 |
| Stroke; n (%) | 9 (0.2%) | 5 (0.2%) | 4 (0.2%) | 1.56 (0.40 to 6.03) | 5 (0.2%) | 2 (0.2%) | 1 (0.2%) | 2 (0.2%) | AP: 0.71 (0.03 to 16.21)18 AT: 0.83 (0.06 to 11.21)18 |
| Additional coronary intervention; n (%) | 475 (10.1%) | 272 (9.8%) | 203 (10.6%) | 1.03 (0.85 to 1.26) | 293 (11.3%) | 109 (10.7%) | 52 (12.8%) | 132 (11.4%) | AP: 1.14 (0.82 to 1.61)19 AT: 1.17 (0.88 to 1.55)19 |
| MACCE; n (%) | 586 (12.5%) | 337 (12.2%) | 249 (13.0%) | 1.06 (0.89 to 1.27) | 350 (13.5%) | 132 (12.9%) | 57 (14.0%) | 161 (13.9%) | AP: 1.10 (0.80 to 1.51)20 AT: 1.21 (0.94 to 1.51)20 |
Adjusted models included: PS (including year, age, gender, anticoagulants, ischaemic heart disease (ever), hypertension, MI (ever), heart failure, STEMI only and previous surgery (ACS); and including year, age, gender, MI (ever), previous CABG/PCI and hypercholesterolaemia (STEMI)) and also adjusted for the following confounders which remained in the model after backwards elimination: age, gender, BMI, ethnic group, smoking category, previous MI, previous CABG/PCI, previous bleed, previous surgery, previous ischaemic heart disease, diabetes, hypertension, hypercholesterolaemia, peripheral vascular disease, stroke, heart failure, peptic ulcer disease, haemodialysis or renal disease, cancer, clotting disorder, anaemia, liver cirrhosis, NSAIDs, steroids, PPIs, anticoagulants and Charlson Comorbidity Index.
AC, aspirin and clopidogrel; ACS, acute coronary syndrome; AP, aspirin plus prasugrel; AT, aspirin plus ticagrelor; BMI, body mass index; CABG, coronary artery bypass graft; CPRD, Clinical Practice Research Datalink; HES, Hospital Episode Statistics; MACCE, major adverse cardiovascular and cerebrovascular events; MI, myocardial infarction; NSAIDs, non-steroidal anti-inflammatory drugs; PCI, percutaneous coronary intervention; PPIs, proton pump inhibitors; PS, propensity score; SA, sensitivity analysis; STEMI, ST-elevation myocardial infarction.