TABLE 1.
Study population characteristics.
| ME/CFS | Controls | p‐value | ||
|---|---|---|---|---|
| n | 18 | 17 | NA | |
| Age (years) | 44.4 ± 7.9 | 44.2 ± 13.4 | 0.87 | |
| BMI | 27.8 ± 5.4 | 29.9 ± 5.8 | 0.26 | |
| Type of onset | Sudden | 83% | NA | NA |
| Gradual | 17% | NA | NA | |
| Bell Disability Scale | Median (IQR) | 30 (17.5) | 100 (10) | p < 0.0001 |
| SF‐36 PCS | Physical component summary | 25.2 ± 6.7 | 56.2 ± 5.0 | p < 0.0001 |
| SF‐36 MCS | Mental component summary | 46.0 ± 8.1 | 54.5 ± 6.9 | p = 0.0001 |
| MFI total | Multi‐dimensional fatigue inventory | 84.4 ± 7.7 | NA | NA |
| CPET parameters (median (IQR)) | VO2peak (mL/kg/min) | 18.45 (3.775) | 19.2 (3.4) | 0.19 |
| VO2@VT (mL/kg/min) | 9.2 (2.6) | 10.5 (2.6) | 0.01 | |
| HRpeak (bpm) | 156 (22.25) | 161 (26) | 0.59 | |
| RERpeak | 1.25 (0.1375) | 1.22 (0.11) | 1 | |
| Work@peak (watts) | 111.5 (25.75) | 127 (26) | 0.08 | |
| Time to peak (s) | 454.5 (94.75) | 529 (100) | 0.02 |
Note: Shown are the mean and standard deviation for demographic parameters in ME/CFS patients and control subjects, except where otherwise indicated. For the Bell disability scale and SF‐36, a higher number corresponds to better health. For the MFI total score, a higher number corresponds to increased fatigue. VT, ventilatory threshold; HR, heart rate; RER, respiratory exchange ratio. The p‐values are from Wilcoxon rank sum tests comparing ME/CFS and control groups. NA, not applicable.