Table 2

1 Year change of heart rate variability and frequency of premature complexes between baseline and the 1 year measurement

Day workers Shift workers p Value of difference between day and shift worker
Mean number of night shifts worked between the baseline and repeated measurement063
Frequency of premature complexes (%):
 Decrease of PAC54.643.70.62-151
 No change in PAC4.60.0
 Increase in PAC40.956.3
 Decrease of PVC45.420.40.032-151
 No change in PVC27.330.6
 Increase in PVC27.348.9
Heart rate variability:
 Heart rate (bpm)1.83−2.082-150 0.08
 SDNNi (ms)−7.02-150 −2.00.2
 Loglow (10−3 log ms)−36.9−29.90.84
 Loghigh (10−3 log ms)−83.92-150 −16.20.06
 % lf1.99−0.720.16
  • PAC=premature atrial complexes; PVC=premature ventricular complexes; SDNNi=mean of all 5 minute standard deviations of NN intervals; Loglow=power in the low frequency range (0.05–015 Hz) in logarithmic units; Loghigh=power in the high frequency range (0.15–0.40 Hz.) in logarithmic units; % lf=low frequency power (0.05–0.15 Hz) in normalised units.

  • 2-150 p<0.05 v baseline.

  • 2-151 p Value according to Wilcoxon two sample test.