Table 3

Associations of treatments with the 3-month event outcomes

Crude HR (95% CI)P valueAdjusted HR
(95% CI)
P valueIPTW*, weighted HR (95% CI)P value
Primary outcome
 Other combination1 (ref.)1 (ref.)1 (ref.)
 Aspirin monotherapy0.98 (0.79 to 1.22)0.88141.17 (0.93 to 1.47)0.16591.05 (0.76 to 1.44)0.7762
 Clopidogrel–aspirin0.88 (0.71 to 1.10)0.27410.92 (0.73 to 1.15)0.45430.82 (0.59 to 1.13)0.2211
All stroke
 Other combination1 (ref).1 (ref.)1 (ref.)
 Aspirin monotherapy0.94 (0.75 to 1.17)0.55741.11 (0.88 to 1.40)0.37300.98 (0.71 to 1.36)0.9126
 Clopidogrel–aspirin0.84 (0.68 to 1.06)0.13830.87 (0.69 to 1.09)0.23310.77 (0.56 to 1.06)0.1127
All-cause mortality
 Other combination1 (ref.)1 (ref.)1 (ref.)
 Aspirin monotherapy2.85 (0.90 to 8.98)0.07443.93 (1.22 to 12.66)0.021810.66 (2.79 to 40.67)0.0005
 Clopidogrel–aspirin2.51 (0.79 to 7.98)0.11842.87 (0.89 to 9.23)0.07767.88 (2.06 to 30.16)0.0026
MI†
 Other combination1 (ref.)
 Aspirin monotherapy1.94 (0.10 to 36.13)0.6574Non-estimableNon-estimable
 Clopidogrel–aspirin3.23 (0.18 to 59.18)0.4286Non-estimableNon-estimable
Ischaemic stroke
 Other combination1(ref.)1(ref.)1(ref.)
 Aspirin monotherapy0.93 (0.75 to 1.16)0.53441.10 (0.87 to 1.39)0.41560.97 (0.70 to 1.34)0.8401
 Clopidogrel–aspirin0.84 (0.67 to 1.05)0.12250.86 (0.69 to 1.09)0.20670.76 (0.55 to 1.05)0.0914
Haemorrhagic stroke
 Other combination1(ref.)
 Aspirin monotherapy0.89 (0.16 to 5.01)0.8960Non-estimableNon-estimable
 Clopidogrel–aspirin1.01 (0.18 to 5.69)0.9942Non-estimableNon-estimable
  • Adjusted variables: age; male sex; initial NIHSS score; arrival time; TOAST classification; history of TIA, stroke, CAD and PAD; HTN; DM; dyslipidaemia; smoking; atrial fibrillation; prior antiplatelet, antihypertensive, antidiabetic, statin or lipid-lowering agent use; multiple lesions; LASO; discharge medications of antihypertensives, antidiabetics, statins and lipid-lowering agents; creatinine; haemoglobin; platelet count; LDL cholesterol; glucose; and SBP.

  • *Weighted Cox proportional hazards model with robust standard errors.

  • †Cox PHs regression using Firth’s penalised maximum likelihood method.

  • CAD, coronary artery disease; DM, diabetes mellitus; HTN, hypertension; IPTW, inverse probability of treatment weighting; LASO, large artery stenosis/occlusion; LDL, low-density lipoprotein; NIHSS, National Institutes of Health Stroke Scale; PAD, peripheral artery disease; PHs, proportional hazards; SBP, systolic blood pressure; TIA, transient ischaemic attack; TOAST, Trial of Org 10 172 in Acute Stroke Treatment.