Table 2.

Multivariable analysis of IV tPA treatment by age group

Treatment	Rate of IV tPA	aOR (95% CI) from model 1	aOR (95% CI) from model 2	aOR (95% CI) from model 3	aOR (95% CI) from model 4
IV tPA among patients without contraindications	49 456/793 175 (6.2)
Young adults	5181/71 860 (7.2)	1.19 (1.15 to 1.22)	1.13 (1.10 to 1.17)	1.20 (1.16 to 1.24)	1.19 (1.15 to 1.22)
Old adults	44 275/721 315 (6.1)	1.00	1.00	1.00	1.00
IV tPA among patients without contraindication and with onset-to-door time ≤3.5 hours	45 842/232 905 (19.7)
Young adults	4768/20 191 (23.6)	1.29 (1.25 to 1.34)	1.20 (1.15 to 1.24)	1.24 (1.20 to 1.29)	1.23 (1.19 to 1.28)
Old adults	41 074/212 714 (19.3)	1.00	1.00	1.00	1.00

Model 1: logistic regression model without adjustment.

Model 2: adjusted for gender, insurance, BMI, previous stroke/TIA, previous CAD/prior MI, diabetes, hypertension, have smoking experience or behaviour, atrial fibrillation/flutter, glycated, haemoglobin, diastolic blood pressure, hypoglycaemic drugs, antihypertensive drugs, antiplatelet drugs, lipid-lowering drugs and hospital level.

Model 3: adjusted for were in-hospital NIHSS score, gender, insurance, BMI, previous stroke/TIA, previous CAD/prior MI, diabetes, hypertension, have smoking experience or behaviour, atrial fibrillation/flutter, glycated haemoglobin, diastolic blood pressure, hypoglycaemic drugs, antihypertensive drugs, antiplatelet drugs, lipid-lowering drugs and hospital level. Patients (n=154 052) with missing values on NIHSS score were not included in this analysis.

Model 4: results from multiple imputation.

aOR, adjusted OR; BMI, body mass index; CAD, coronary artery disease; MI, myocardial infarction; NIHSS, National Institutes of Health Stroke Scale; IV tPA, intravenous tissue plasminogen activator.