Table 2

Baseline Characteristics and Clinical Outcome: Univariate Analysis

Death, MI or Ischemia-Related HospitalUnivariate Cox Regression
No (n = 485)Yes (n = 73)
No.%No.%Odds Ratio99% CIp Value
Age (yr) (mean± SD)61.5 ± 8.261.2 ± 9.30.960.67–1.380.76
 ≥60 yr29961.74460.30.950.52–1.770.84
Men41786.06284.90.930.40–2.160.83
White41886.26082.20.760.34–1.660.36
Symptoms: angina (within 6 wk of entry or on QV ETT or other stress test or with EPI on QV AECG)33168.36082.22.060.94–4.540.08
Drug regimen
 Atenolol/nifedipine24249.94257.5
 Diltiazem/isosorbide dinitrate24350.13142.50.750.41–1.390.22
History
 Previous MI20241.72432.90.710.37–1.340.16
 Diabetes7615.71419.21.260.59–2.710.44
 Heart failure153.111.40.440.03–5.940.42
 Peripheral vascular disease336.856.90.980.30–3.240.97
 Hypertension18437.92534.30.880.46–1.660.59
 Current smoker7816.31216.41.000.44–2.260.99
 Ever smoked31765.44967.11.070.57–2.040.78
 Previous PTCA8517.51520.61.210.58–2.560.51
 Previous CABG275.645.50.980.26–3.720.98
 Previous PTCA or CABG, or both10722.11926.01.240.62–2.460.43
 Family history of CAD <55 yr19540.23649.31.390.76–2.540.16
Physical examination (mean± SD)
 SBP (mm Hg)138.4 ± 19.1142.2 ± 21.51.100.94–1.290.11
 DBP (mm Hg)79.5 ± 9.979.1 ± 10.70.970.71–1.320.78
 HR (beats/min)69.3 ± 11.869.3 ± 11.31.000.77–1.290.99
Coronary angiography (stenosis ≥50%)1.130.76–1.670.43
 1 vessel12024.71621.91.00
 2 vessel18538.12635.61.050.47–2.390.87
 3 vessel18037.13142.51.260.57–2.770.46
 Proximal stenosis ≥50%30162.35272.21.510.77–2.970.12
 Proximal LAD stenosis ≥50%15532.1334581.790.93–3.450.02
 Proximal stenosis ≥70%19239.83548.61.410.77–2.600.14
 Definite complex plaque16636.92637.71.040.55–1.990.88
 Definite or probable complex plaque24554.53550.70.880.47–1.630.59
Ejection fraction
 <35%71.511.50.830.06–11.280.85
 35% to 49%459.868.70.870.28–2.700.75
 50% to 64%20444.32739.10.840.43–1.630.50
 ≥65%20544.53550.71.00
 Not available244
 by 10% unit1.050.76–1.440.70
QV rest 12-lead ECG
 Abnormal22947.24257.51.460.80–2.690.11
 Q waves5812.01013.71.150.48–2.790.66
 ST depression <0.1 mm10822.32432.91.660.87–3.150.04
 T wave abnormalities14529.92534.31.200.63–2.260.47
QV AECG (mean± SD)
 No. of EPIs4.7 ± 5.06.2 ± 6.61.031.00–1.070.02
 Duration of EPIs40.8 ± 50.556.4 ± 92.71.031.00–1.070.03
 HR change (max− mean)56.4 ± 14.854.5 ± 15.30.920.74–1.140.30
QV ETT (mean± SD)
 Total exercise time7.0 ± 3.25.8 ± 2.80.880.78–0.990.006
 Final HR132.0 ± 18.8130.3 ± 19.30.960.82–1.130.51
 % age-predicted HR83.3 ± 11.982.0 ± 11.60.920.72–1.190.43
 Max ST depression2.4 ± 1.02.5 ± 1.11.080.81–1.450.48

For the continuous variables ischemic episode (EPI) on qualifying visit ambulatory electrocardiogram (QV AECG) and total exercise time, the odds ratio corresponds to a 1-unit increase; for all other continuous variables (age, systolic blood pressure [SBP], diastolic blood pressure [DBP], heart rate [HR], ejection fraction, duration of ischemia, heart rate change, final heart rate, % age-predicted heart rate) the odds ratio corresponds to a 10-unit increase. CAD = coronary artery disease; CI = confidence interval; ETT = Asymptomatic Cardiac Ischemia Pilot study protocol exercise treadmill + stress test; LAD = left anterior descending coronary artery; other abbreviations as in Table 1.