SLE (n=54) | HC (n=54) | P value | |||
HRV indices, median (IQR)* | |||||
SDNN, ms | 28.3 | (21.1–37.9) | 36.7 | (28.5–53.4) | 0.019 |
RMSSD, ms | 18.3 | (8.8–27.0) | 25.7 | (18.4–38.0) | 0.007 |
LF, ms2 | 61.0 | (33.3–129) | 77.0 | (48.8–185) | 0.08 |
HF, ms2 | 34.8 | (10.6–73.0) | 84.3 | (33.4–198) | <0.001 |
TP, ms2 | 215 | (125-445) | 373 | (213-788) | 0.011 |
LF/HF ratio | 2.05 | (1.03–3.94) | 1.02 | (0.44–2.37) | 0.001 |
CARTs, median (IQR)* | |||||
RS ratio | 1.08 | (1.01–1.14) | 1.26 | (1.14–1.35) | <0.001 |
EI ratio | 1.15 | (1.09–1.28) | 1.22 | (1.11–1.32) | 0.042 |
VM ratio | 1.45 | (1.24–1.60) | 1.63 | (1.47–1.80) | <0.001 |
CAN stage, n (%) | |||||
No CAN | 25 | (46.3) | 42 | (77.8) | 0.001 |
Early CAN | 16 | (29.6) | 11 | (20.4) | |
Definitive CAN | 13 | (24.1) | 1 | (1.9) |
*Natural logarithm applied for parametric analyses. Values in bold are considered significant (p<0.05).
CAN, cardiovascular autonomic neuropathy; CARTs, cardiovascular autonomic reflex tests; EI, expiration/inspiration; HF, high frequency power; HRV, heart rate variability; LF, low frequency power; RMSSD, root mean square of successive differences between normal heartbeats; RS, response to standing; SDNN, SD of all NN intervals; TP, total power; VM, Valsalva manoeuvre.