Table 2

Event prediction based on continuous variables

Univariable analysisMultivariable analysis: model 1 (8 leads)Multivariable analysis: model 2 (3 leads)
WaldP valueHR (95% CI)WaldP valueHR (95% CI)WaldP valueHR (95% CI)
Prediction of 5-year all-cause mortality
Age (years) 48.9 <0.001 1.043 (1.031 to 1.055)37.5<0.0011.038 (1.026 to 1.051)32.0<0.0011.035 (1.023 to 1.048)
Heart rate (bpm) 30.8 <0.001 1.019 (1.012 to 1.026)24.2<0.0011.018 (1.011 to 1.025)19.5<0.0011.016 (1.009 to 1.024)
LVEF (%) 30.1 <0.001 0.959 (0.945 to 0.973)11.40.0010.972 (0.955 to 0.988)11.70.0010.972 (0.956 to 0.988)
QRS duration (ms) 26.6 <0.001 1.009 (1.006 to 1.013)
QTc interval (ms) 20.3 <0.001 1.006 (1.004 to 1.009)
QRS-T angle (o) 26.1 <0.001 1.010 (1.006 to 1.014)8.880.0031.006 (1.002 to 1.010)8.130.0041.006 (1.002 to 1.010)
TpTe interval (ms)1.090.2961.002 (0.998 to 1.006)
log2 (QRS n-pl 8 leads) 17.5 <0.001 1.329 (1.163 to 1.519)16.8<0.0011.339 (1.165 to 1.540)
log2 (T wave n-pl 8 leads)0.870.3491.061 (0.938 to 1.200)
log2 (QRS n-pl 3 leads) 35.0 <0.001 1.437 (1.275 to 1.621)20.6<0.0011.338 (1.180 to 1.517)
log2 (T wave n-pl 3 leads)3.390.0661.109 (0.993 to 1.237)
Prediction of 5-year ICD shocks
Age (years)0.430.5101.004 (0.992 to 1.016)
Heart rate (bpm)1.730.1880.994 (0.984 to 1.003)
LVEF (%)0.010.9751.000 (0.985 to 1.014)
QRS duration (ms)0.230.8791.000 (0.995 to 1.004)
QTc interval (ms)0.150.6961.001 (0.997 to 1.004)
QRS-T angle (o)0.910.3400.998 (0.995 to 1.002)
TpTe interval (ms)0.500.4760.998 (0.992 to 1.004)
log2 (QRS n-pl 8 leads) 6.61 0.010 1.233 (1.051 to 1.447)
log2 (T wave n-pl 8 leads) 17.7 <0.001 1.364 (1.180 to 1.576)17.7<0.0011.364 (1.180 to 1.576)
log2 (QRS n-pl 3 leads)1.330.2491.087 (0.943 to 1.253)
log2 (T wave n-pl 3 leads) 4.96 0.026 1.159 (1.018 to 1.321)4.960.0261.159 (1.018 to 1.321)
  • Univariable and multivariable (backwards stepwise elimination) Cox regression analyses for the prediction of outcome events during 5-year follow-up (see the text for the distinction of the two multivariable models). Risk factors entered as continuous variables, n-pl indices of QRS and T wave loops entered after logarithmic transformation. Statistically significant results are shown in bold. In addition to the p values, the levels of Wald statistics are also shown. The grey areas indicate the variables excluded in the different multivariable models.

  • bpm, beats per minute; ICD, implantable cardioverter-defibrillator; LVEF, left ventricular ejection fraction; n-pl, non-planarity; TpTe, T-peak to T-end.