Table 2.
Stratified Outcomes Analysis for Medical Therapy Alone Versus CABG by Presence of Angina at Baseline
| Event | Medical Therapy Alone (n = 602) |
CABG + Medical Therapy (n = 610) |
Adjusted Hazard Ratio for CABG + Medical Therapy (95% CI)*† |
p Value |
|---|---|---|---|---|
| No angina at baseline (n = 442) | (n = 225) | (n = 217) | ||
| All-cause mortality | 0.68 (0.50–0.94) | 0.02 | ||
| Number of events (crude event rate, %) | 96 (42.7%) | 71(32.7%) | ||
| KM estimate of 5-yr event rate (%) | 41.0% | 31.9% | ||
| Adjusted Cox proportional hazard estimates of cumulative risk of all-cause death at 5 yrs (%) | 32.9% | 25.0% | ||
| All-cause mortality or all-cause hospitalization | 0.80 (0.64–1.00) | 0.05 | ||
| Number of events (crude event rate, %) | 172 (76.4%) | 149 (68.7%) | ||
| KM estimate of 5-yr event rate (%) | 79.0% | 68.1% | ||
| Angina at baseline (n =770) | (n = 377) | (n = 393) | ||
| All-cause mortality | 0.89 (0.71–1.13) | 0.34 | ||
| Number of events (crude event rate, %) | 149 (39.5%) | 147 (37.4%) | ||
| KM estimate of 5-year event rate (%) | 39.8% | 36.8% | ||
| Adjusted Cox proportional hazard estimates of cumulative risk of all-cause death at 5 yrs (%) | 37.2% | 33.2% | ||
| All-cause mortality or all-cause hospitalization | 0.78 (0.66–0.93) | <0.001 | ||
| Number of events (crude event rate, %) | 270 (71.6%) | 250 (63.6%) | ||
| KM estimate of 5-year event rate (%) | 72.2% | 63.8% | ||
Of 1,212 patients randomized in STICH, 1,205 with known angina status at baseline were included in the multivariable statistical analysis. Implantation of a left ventricular assist device during follow-up was considered as equivalent to death (n = 1).
All-cause death analysis was adjusted for LVEF, age, BMI (<35), log of creatinine (0 to 0.4), peripheral vascular disease, mitral regurgitation, beta-blocker at baseline, and atrial fibrillation/flutter. The p interaction for angina and treatment (medical therapy alone or CABG) = 0.14
All-cause death plus all-cause hospitalization analyses were adjusted for treatment group (CABG vs. medical therapy alone), LVEF, age, white race, log of creatinine (< 0.4), hemoglobin, mitral regurgitation, and NYHA classification. The p interaction for angina and treatment (medical therapy alone or CABG) = 0.99.
The following values were assigned to baseline covariates for adjusted event rates: age = 60 years; LVEF = 28; BMI = 27; log2(creatinine) = 0.14; PVD = 0.15; mitral valve regurgitation (moderate/severe) = 0.18; beta-blocker = 0.85; and atrial fibrillation/flutter = 0.13.
KM = Kaplan-Meier; LVEF = left ventricular ejection fraction. Other abbreviations as in Table 1.