Table 6.
Risks for ACS According to Various Subgroups
| Unadjusted | Multivariable‐adjusted | IPTW adjusted* | |||||
|---|---|---|---|---|---|---|---|
| No. (%) | HR (95% CI) | P value | HR (95% CI) | P value | HR (95% CI) | P value | |
| Definite positive ERGT † | 730 (38.5) | ||||||
| No vasodilator (reference) | 132 (7.0) | 1 | 1 | 1 | |||
| Nonnitrate vasodilator | 459 (24.2) | 0.51 (0.19–1.37) | 0.505 | 0.41 (0.14–1.22) | 0.109 | 0.33 (0.11–1.01) | 0.052 |
| Conventional nitrate | 81 (4.3) | 1.33 (0.41–4.37) | 0.637 | 0.99 (0.28–3.49) | 0.989 | 1.10 (0.30–3.97) | 0.888 |
| Combination | 58 (3.1) | 2.09 (0.64–6.86) | 0.224 | 1.25 (0.35–4.46) | 0.733 | 1.61 (0.44–5.87) | 0.472 |
| Intermediate positive ERGT † | 1165 (61.5) | ||||||
| No vasodilator (reference) | 227 (12.0) | 1 | 1 | 1 | |||
| Nonnitrate vasodilator | 728 (38.4) | 1.97 (0.45–8.67) | 0.370 | 2.00 (0.45–8.94) | 0.363 | 2.13 (0.47–9.59) | 0.327 |
| Conventional nitrate | 128 (6.8) | 6.15 (1.31–28.95) | 0.022 | 7.28 (1.48–35.77) | 0.015 | 6.89 (1.38–34.45) | 0.019 |
| Combination | 82 (4.3) | 8.30 (1.72–39.96) | 0.008 | 8.16 (1.65–40.30) | 0.010 | 7.52 (1.45–38.86) | 0.016 |
| Intermediate or high JCSA risk score ‡ | 569 (30.0) | ||||||
| No vasodilator (reference) | 122 (6.4) | 1 | 1 | 1 | |||
| Nonnitrate vasodilator | 328 (17.3) | 0.65 (0.24–1.76) | 0.396 | 0.62 (0.22–1.72) | 0.355 | 0.59 (0.21–1.67) | 0.324 |
| Conventional nitrate | 76 (4.0) | 1.36 (0.44–4.22) | 0.594 | 1.11 (0.34–3.63) | 0.858 | 1.17 (0.34–3.65) | 0.857 |
| Combination | 43 (2.3) | 1.17 (0.29–4.67) | 0.827 | 0.91 (0.22–0.3.82) | 0.893 | 1.01 (0.23–4.47) | 0.985 |
| Low JCSA risk score ‡ | 1326 (70.0) | ||||||
| No vasodilator (reference) | 237 (12.5) | 1 | 1 | 1 | |||
| Nonnitrate vasodilator | 859 (45.3) | 1.77 (0.40–7.80) | 0.449 | 1.56 (0.35–6.93) | 0.562 | 1.59 (0.35–7.13) | 0.546 |
| Conventional nitrate | 133 (7.0) | 6.00 (1.24–28.99) | 0.026 | 5.71 (1.15–28.34) | 0.033 | 5.64 (1.13–28.07) | 0.035 |
| Combination | 97 (5.1) | 11.29 (2.43–52.41) | 0.002 | 10.79 (2.24–51.95) | 0.003 | 10.73 (2.23–51.67) | 0.003 |
Values are expressed as n (%). ACS indicates acute coronary syndrome; ERGT, ergonovine provocation test; HR, hazard ratio; IPTW, inverse probability of treatment weighting; and JCSA, Japanese Coronary Spasm Association.
*
Adjusted by IPTW and variables included in multivariable‐adjusted model.
†
Adjusted by center identifier, ischemic heart disease, dyslipidemia, atrial fibrillation or flutter, current or ex‐smoking, ST‐T changes during chest pain, and significant coronary stenosis.
‡
Adjusted by center identifier, ischemic heart disease, dyslipidemia, and atrial fibrillation or flutter.