Variables | Model A | Model B | Model C | |||
HR (95% CI) | P value | HR (95% CI) | P value | HR (95% CI) | P value | |
Ambulance cardiac status | ||||||
Suspected STEMI (ref) | 1 | – | 1 | – | 1 | – |
Other suspected ACS | 1.22 (0.94 to 1.59) | 0.14 | 1.11 (0.85 to 1.44) | 0.45 | 0.85 (0.65 to 1.11) | 0.22 |
ACS not suspected | 4.41 (3.69 to 5.27) | <0.01 | 3.29 (2.74 to 3.95) | <0.01 | 1.48 (1.22 to 1.80) | <0.01 |
Not attended by ambulance | 1.14 (0.92 to 1.42) | 0.24 | 1.23 (0.99 to 1.54) | 0.06 | 0.73 (0.58 to 0.92) | 0.01 |
Demographics | ||||||
Age, per year | – | – | 1.045 (1.039 to 1.051) | <0.01 | 1.015 (1.008 to 1.022) | <0.01 |
Sex | – | – | ||||
Male | 0.99 (0.86 to 1.15) | 0.94 | 1.14 (0.98 to 1.32) | 0.09 | ||
Female (ref) | 1 | – | 1 | – | ||
Ethnicity | – | – | – | – | ||
Māori | 1.09 (0.84 to 1.41) | 0.53 | ||||
Pacific | 1.27 (0.92 to 1.76) | 0.15 | ||||
Indian | 0.94 (0.58 to 1.53) | 0.81 | ||||
Asian | 0.78 (0.48 to 1.27) | 0.31 | ||||
NZ Euro/other (ref) | 1 | – | ||||
NZDep13 | – | – | – | – | ||
1–2 (ref) | 1 | – | ||||
3–4 | 1.09 (0.84 to 1.41) | 0.51 | ||||
5–6 | 1.24 (0.97 to 1.60) | 0.09 | ||||
7–8 | 1.27 (1.00 to 1.62) | 0.05 | ||||
9–10 | 1.33 (1.04 to 1.70) | 0.02 | ||||
Modified Charlson Comorbidity Index | – | – | – | – | ||
0 (ref) | ||||||
1–2 | 1 | – | ||||
≥3 | 1.01 (0.84 to 1.21) | 0.91 | ||||
1.24 (1.03 to 1.49) | 0.02 | |||||
Coronary intervention status | – | – | – | – | ||
No angiography (ref) | 1 | – | ||||
Angiography without intervention | 0.25 (0.19 to 0.34) | <0.01 | ||||
Angiography with intervention | 0.12 (0.10 to 0.16) | <0.01 | ||||
Hospital status | – | – | – | – | ||
Routine 24/7 PCI primary PCI | 1.13 (0.96 to 1.33) | 0.13 | ||||
Base hospital w/o 24/7 PCI (ref) | 1 | – | ||||
Rural hospital | 1.04 (0.76 to 1.44) | 0.8 |
Model A: unadjusted.
Model B: adjusted by age and sex.
Model C: adjusted for age, sex, ethnicity, NZDep quintile, non-cardiac comorbidity (0, 1–2, >2), coronary intervention status (no angiography, angiography without intervention, angiography with intervention), hospital status (primary PCI, non-primary PCI with catheterisation lab, hospital without catheterisation lab).
ACS, acute coronary syndrome; NZDep13, New Zealand Deprivation Index 2013; PCI, percutaneous coronary intervention; STEMI, ST-segment elevation myocardial infarction.