Table 1 Baseline characteristics of the study participants

Demographics

Age (years)

 < 0.001

 < 55

11,786 (29.32%)

9475 (31.4%)

2311 (23.06%)

 55–65

11,116 (27.65%)

8562 (28.37%)

2554 (25.48%)

 65–75

10,005 (24.89%)

7218 (23.92%)

2787 (27.81%)

 >  = 75

7295 (18.15%)

4924 (16.32%)

2371 (23.66%)

Sex

 < 0.001

 Male

29,815 (74.16%)

22,963 (76.09%)

6852 (68.36%)

 Female

10,387 (25.84%)

7216 (23.91%)

3171 (31.64%)

Access (n, %)

 < 0.001

 Emergency

4107 (10.52%)

3287 (11.24%)

820 (8.37%)

 External referral

22,944 (58.77%)

16,520 (56.49%)

6424 (65.56%)

 Family members or others Referral

9852 (25.24%)

8098 (27.69%)

1754 (17.9%)

 Hospital ward

444 (1.14%)

249 (0.85%)

195 (1.99%)

 Self-referral

1694 (4.34%)

1088 (3.72%)

606 (6.18%)

Time from onset to treatment

 < 0.001

 < 24

28,664 (71.3%)

22,427 (74.31%)

6237 (62.23%)

 > 24 h

7873 (19.58%)

4918 (16.3%)

2955 (29.48%)

 Uncertain

3665 (9.12%)

2834 (9.39%)

831 (8.29%)

Educational level (%)

0.0019

 College or above

3097 (7.7%)

2396 (7.94%)

701 (6.99%)

 Below junior college

37,105 (92.3%)

27,783 (92.06%)

9322 (93.01%)

Regions

 < 0.001

 Eastern

15,929 (39.62%)

11,577 (38.36%)

4352 (43.42%)

 Central

18,101 (45.03%)

13,961 (46.26%)

4140 (41.3%)

 western

6172 (15.35%)

4641 (15.38%)

1531 (15.27%)

Medical history (n, %)

 Previous MI

2894 (7.2%)

1751 (5.8%)

1143 (11.4%)

 < 0.001

 Previous PCI

750 (1.87%)

496 (1.64%)

254 (2.53%)

 < 0.001

 Previous CABG

144 (0.36%)

60 (0.2%)

84 (0.84%)

 < 0.001

 Previous heart failure

938 (2.33%)

379 (1.26%)

559 (5.58%)

 < 0.001

 Previous stroke

3524 (8.77%)

2525 (8.37%)

999 (9.97%)

 < 0.001

 Previous peripheral arterial disease

271 (0.67%)

157 (0.52%)

114 (1.14%)

 < 0.001

 Bleeding history

459 (1.14%)

330 (1.09%)

129 (1.29%)

0.1188

Cardiovascular risk factors (n, %)

 Diabetes mellitus

7504 (18.67%)

5166 (17.12%)

2338 (23.33%)

 < 0.001

 Hypertension

19,661 (48.91%)

13,958 (46.25%)

5703 (56.9%)

 < 0.001

 Hyperlipidemia

2808 (6.98%)

1991 (6.6%)

817 (8.15%)

 < 0.001

 Family history of premature CAD

1237 (3.08%)

952 (3.15%)

285 (2.84%)

0.1151

 Current smoker

18,661 (46.42%)

13,412 (44.44%)

5249 (52.37%)

 < 0.001

Treatment strategy (n, %)

 Primary PCI

14,186 (35.29%)

12,998 (43.07%)

1188 (11.85%)

 < 0.001

 Elective PCI

9260 (23.03%)

6389 (21.17%)

2871 (28.64%)

 < 0.001

 Conservation

5149 (12.81%)

3580 (11.86%)

1569 (15.65%)

 < 0.001