Presenting features of patients
| Characteristics | Low-risk (n=111) | Non-low-risk (n=69) | Difference between low-risk vs non-low-risk, % for counts and absolute difference for age (95% CI) | Non-low-risk, referred to hospital (n=56) | Non-low-risk, managed at home (n=13) |
| Age, years | 52 (11.8) | 69 (10.9) | −17.7 (−21.1 to −14.3)* | 69 (11.0) | 69 (11.4) |
| Women | 67 (60.4) | 21 (30.4) | 29.9 (14.2 to 43.6) | 18 (32.1) | 3 (23.1) |
| Ethnicity | |||||
| European | 74 (66.7) | 60 (87.0) | −20.3 (−32.0 to −6.6) | 48 (85.7) | 12 (92.3) |
| Māori | 25 (22.5) | 7 (10.1) | 12.4 (−0.1 to 23.1) | 6 (10.7) | 1 (7.7) |
| Pacific Peoples | 3 (2.7) | 1 (1.4) | 1.3 (−6.5 to 7.0) | 1 (1.8) | 0 (0.0) |
| Asian | 7 (6.3) | 0 (0.0) | 6.3 (−1.2 to 13.0) | 0 (0.0) | 0 (0.0) |
| Other | 2 (1.8) | 1 (1.4) | 0.4 (−7.2 to 5.7) | 1 (1.8) | 0 (0.0) |
| Risk factors and history | |||||
| Hypertension | 33 (29.7) | 42 (60.9) | −31.1 (−45.1 to −15.4) | 33 (58.9) | 9 (69.2) |
| Dyslipidaemia | 20 (18.0) | 29 (42.0) | −24.0 (−38.0 to −9.5) | 21 (37.5) | 8 (61.5) |
| Diabetes mellitus | 8 (7.2) | 5 (7.2) | 0.0 (−10.3 to 8.3) | 5 (8.9) | 0 (0.0) |
| Current smoker | 39 (35.1) | 13 (18.8) | 16.3 (1.8 to 28.9) | 11 (19.6) | 2 (15.4) |
| Family history of premature CAD | 36 (32.4) | 16 (23.2) | 9.2 (−5.4 to 22.4) | 11 (19.6) | 5 (38.5) |
| Known ischaemic heart disease | 10 (9.0) | 32 (46.4) | −37.4 (−50.5 to −23.4) | 26 (46.4) | 6 (46.2) |
| Onset of symptoms to presentation, hours | 14 (3.9–39.5) | 15 (1.4–40.5) | 1*† | 14 (1.4–38.6) | 37 (7.0–48.2) |
| Proportion of patients presenting <3 hours from symptom onset, hours | 20 (18.7) | 22 (34.4) | −13.9 (−27.9 to −0.3) | 19 (37.3) | 3 (23.1) |
| Proportion of patients presenting ≥3 hours from symptom onset, hours | 87 (81.3) | 42 (65.6) | 17.5 (3.1 to 31.9) | 32 (62.7) | 10 (76.9) |
Data are presented as n (%) or mean (SD) or median (IQR).
*Absolute difference (95% CI) between patients identified as low-risk and non-low-risk.
†Not appropriate to construct CIs; Mann-Whitney U test was p=0.78, indicating it is unlikely that there is a difference in time from symptom onset to presentation between low-risk and non-low-risk groups.
CAD, coronary artery disease.