| Incidence Rate (per 10,000 person-years) | Unadjusted Rate Ratio/Hazard Ratio (with 95 % confidence intervals) | P value | Adjusted Rate Ratio/Hazard Ratioa(with 95 % confidence intervals) | P value | |
---|---|---|---|---|---|---|
Cohort | Unexplained CP | Known CAD | Â | Â | Â | Â |
 Any Return for CP | 8.2 | 7.1 | 1.25 (1.16-1.35)b | <0.0001* | 1.54 (1.43-1.66)b | <0.0001* |
 Unexplained CP Return | 7.5 | 3.9 | 2..23 (2.05-2.40)b | <0.0001* | 2.63 (2.43-2.87)b | <0.0001* |
 Death | 0.1 | 0.2 | 0.51 (0.39-0.68)b,c | 0.0001* | 0.61 (0.45-0.83)b,c | 0.0018* |