Background
Methods
Statistical analysis
Results
Characteristics of the study population
Number of patients | Baseline (n = 53) | Follow-up (n = 53) |
p Values |
---|---|---|---|
Disease activity, median (IQR) | |||
SLEDAI | 6 (4–9) | 4 (2–6) |
<0.001
|
BILAG | 9 (8–16) | 2 (1–15) |
<0.001
|
PGA | 1.5 (1.2–1.8) | 0.9 (0.6–1.4) |
<0.001
|
Medications, n (%) | |||
HCQ | 35 (66) | 36 (68) | 1.000 |
AZA | 9 (17) | 8 (15) | 1.000 |
MTX | 10 (19) | 15 (28) | 0.360 |
MMF | 11 (21) | 10 (19) | 1.000 |
CS | 13 (25) | 12 (23) | 1.000 |
Parameters affecting HRV, n (%) | |||
Tobacco exposure | 14 (26) | 16 (30) | 0.829 |
Caffeine | 27 (51) | 30 (57) | 0.697 |
Medications ↑HRV | 12 (23) | 11 (21) | 1.000 |
Medications ↓HRV | 13 (25) | 11 (21) | 0.816 |
HRV is inversely associated with disease activity and flare at baseline
Independent variables | ||||
---|---|---|---|---|
Dependent variables | RMSSD | pNN50 | HF | LF/HF |
BILAG |
p = 0.259 β = −0.024 |
p
= 0.019
β = −0.385 |
p
= 0.020
β = −0.108 |
p
= 0.024
β = 0.630 |
BILAG mucocutaneous |
p = 0.870 β = 0.002 |
p = 0.124 β = −0.142 |
p = 0.313 β = −0.027 |
p = 0.695 β = 0.062 |
BILAG musculoskeletal |
p = 0.346 β = −0.011 |
p
= 0.043
β = −0.185 |
p
= 0.010
β = −0.066 |
p = 0.100 β = 0.257 |
SLEDAI |
p = 0.683 β = 0.005 |
p = 0.312 β = −0.101 |
p = 0.488 β = −0.020 |
p = 0.073 β = 0.301 |
SLEDAI rash |
p = 0.977 β < 0.001 |
p = 0.420 β = −0.009 |
p = 0.170 β = −0.004 |
p = 0.206 β = 0.024 |
SLEDAI arthritis |
p = 0.531 β < 0.001 |
p = 0.309 β = −0.010 |
p = 0.088 β = −0.005 |
p = 0.446 β = 0.013 |
PGA |
p = 0.651 β < −0.001 |
p
= 0.014
β = −0.026 |
p = 0.154 β = −0.004 |
p = 0.062 β = 0.034 |
SFI |
p = 0.456 β = −0.001 |
p = 0.329 β = −0.012 |
p
= 0.047
β = −0.007 |
p
= 0.008
β = 0.054 |
HRV is inversely related to soluble TNFRII and to IFN-induced cytokines
Independent variables | ||||
---|---|---|---|---|
Dependent variables | RMSSD | pNN50 | HF | LF/HF |
IL-1RA |
p = 0.949 β < −0.001 |
p = 0.286 β = −0.069 |
p
= 0.011
β = −0.037 |
p = 0.067 β = 0.147 |
SCF |
p = 0.133 β = −0.004 |
p
= 0.049
β = −0.042 |
p = 0.373 β = −0.005 |
p
= 0.034
β = 0.076 |
IL-15 |
p = 0.402 β = −0.003 |
p = 0.054 β = −0.054 |
p
= 0.025
β = −0.018 |
p = 0.148 β = 0.069 |
IFN-α |
p = 0.920 β < −0.001 |
p = 0.089 β = −0.079 |
p = 0.063 β = −0.019 |
p = 0.313 β = 0.059 |
IP-10 |
p = 0.202 β = −0.005 |
p = 0.088 β = −0.048 |
p = 0.122 β = −0.012 |
p = 0.189 β = 0.064 |
MIG |
p
= 0.007
β = −0.011 |
p
= 0.015
β = −0.077 |
p
= 0.018
β = −0.021 |
p
= 0.026
β = 0.119 |
sTNFRII |
p
< 0.001
β = −0.007 |
p
= 0.01
β = −0.042 |
p
= 0.039
β = −0.010 |
p
= 0.024
β = 0.064 |
BLySa
|
p = 0.556 β = 0.002 |
p = 0.201 β = −0.026 |
p = 0.140 β = −0.008 |
p = 0.098 β = 0.055 |
Independent variables | RMSSD | pNN50 | HF | LF/HF | ||||
---|---|---|---|---|---|---|---|---|
p Value | β coefficient |
p Value | β coefficient |
p Value | β coefficient |
p Value | β coefficient | |
Model I | ||||||||
IL-1RA | 0.523 | 5.701 | 0.968 | 0.030 |
<0.001
| −10.414 |
0.009
| 1.772 |
SCF | 0.635 | 7.867 | 0.381 | 1.262 |
0.034
| 10.300 | 0.520 | 0.730 |
IFN-α | 0.895 | 1.063 | 0.392 | −0.602 | 0.739 | −0.736 | 0.854 | 0.101 |
IP-10 | 0.762 | 5.658 | 0.725 | 0.567 |
0.001
| 19.838 |
0.005
| −4.126 |
MIG |
0.036
| −34.531 | 0.072 | −2.498 |
<0.001
| −21.391 |
0.003
| 3.526 |
BLySa
| 0.598 | 8.028 | 0.411 | −1.087 |
0.023
| −10.276 | 0.110 | 1.724 |
Model II | ||||||||
IL-1RA | 0.474 | 5.922 | 0.893 | 0.102 |
0.018
| −8.913 |
0.039
| 1.555 |
SCF | 0.559 | 9.075 | 0.384 | 1.259 | 0.185 | 8.802 | 0.488 | 0.927 |
IFN-α | 0.867 | 1.262 | 0.414 | −0.576 | 0.915 | −0.336 | 0.949 | 0.041 |
IP-10 | 0.530 | −8.722 | 0.618 | −0.640 | 0.249 | 6.810 | 0.095 | −2.070 |
sTNFRII |
0.011
| −51.594 | 0.078 | −3.116 |
0.040
| −16.762 | 0.061 | 3.100 |
BLySa
| 0.476 | 10.003 | 0.504 | −0.867 | 0.229 | −7.168 | 0.303 | 1.253 |
Some cytokines associated with HRV are also associated with disease activity
Changes in HRV between visits are associated with changes in SLEDAI
Independent variables | |||||
---|---|---|---|---|---|
Dependent variables | ΔRMSSD | ΔpNN50 | ΔHF | ΔLF/HF | |
Changes in disease activity | ΔBILAG |
p = 0.081 β = −0.036 |
p = 0.605 β = −0.109 |
p = 0.168 β = −0.075 |
p = 0.119 β = 0.542 |
ΔSLEDAI |
p
= 0.007
β = −0.023 |
p = 0.094 β = −0.144 |
p = 0.326 β = −0.023 |
p = 0.431 β = 0.116 | |
ΔPGA |
p = 0.209 β = −0.002 |
p = 0.704 β = −0.006 |
p = 0.067 β = −0.007 |
p = 0.174 β = 0.034 | |
Cytokine changes | ΔsTNFRII |
p = 0.824 β < −0.001 |
p = 0.789 β = 0.011 |
p = 0.168 β = −0.014 |
p
= 0.021
β = 0.150 |
ΔMIG |
p = 0.453 β = −0.004 |
p = 0.963 β = −0.003 |
p = 0.176 β = −0.019 |
p
= 0.003
β = 0.253 | |
ΔBLySa
|
p = 0.298 β = −0.002 |
p = 0.994 β < −0.001 |
p
= 0.036
β = −0.010 |
p = 0.057 β = 0.054 | |
ΔIFN-α |
p = 0.901 β < 0.001 |
p = 0.526 β = 0.037 |
p
= 0.004
β = −0.050 |
p
= 0.012
β = 0.356 | |
ΔIL-1RA |
p = 0.840 β = −0.003 |
p = 0.794 β = −0.044 |
p = 0.199 β = −0.055 |
p
= 0.023
β = 0.646 | |
ΔIP-10 |
p = 0.671 β = −0.001 |
p = 0.679 β = 0.014 |
p = 0.945 β < −0.001 |
p = 0.895 β = 0.008 | |
ΔSCF |
p = 0.085 β = −0.004 |
p = 0.603 β = −0.011 |
p = 0.154 β = −0.008 |
p
= 0.001
β = 0.108 | |
ΔIL-15 |
p = 0.764 β = −0.001 |
p = 0.471 β = 0.033 |
p
= 0.012
β = −0.026 |
p
= 0.010
β = 0.154 |