Table 2.
Pain thresholds and CPM response at baseline, after 3 weeks’ treatment and the change in values for all the groups
| Placebo responders (n=12) | Placebo nonresponders (n=17) | Pregabalin responders (n=16) | Pregabalin nonresponders (n=15) | |
|---|---|---|---|---|
| ePDT (mA) (baseline) | ||||
| – C5 | 3.5 (2.4–7.6) | 3.5 (2.2–5.5) | 3.8 (2.7–4.7) | 3.6 (2.2–5.1) |
| – T10V | 6.1 (3.5–7.8) | 3.5 (2.5–6.8) | 5.7 (4.5–7.6) | 5.2 (4.5–10.4) |
| ePDT (after treatment) | ||||
| – C5 | 5.0 (2.0–6.3) | 2.3 (2.1–4.5) | 4.8 (3.5–6.3)* | 4.5 (3.3–5.4) |
| – T10V | 7.0 (5.0–8.2) | 3.4 (3.0–6.1) | 6.8 (5.8–10.1)† | 6.4 (3.9–7.5) |
| Change ePDT | ||||
| – C5 | −0.1 (−1.3 to 0.5) | −0.3 (−0.7 to 0.6) | 1.3 (0.4–2.0) | 0.4 (−0.9 to 1.3) |
| – T10V | 0.7 (−0.6 to 1.9) | −0.2 (0.8–1.2) | 1.7 (0.0–3.4) | −0.3 (−1.1 to 1.9) |
| CPM response (%) (baseline) | 13 (−3 to 25) | 14 (5–44) | 11 (−12 to 23) | 12 (−19 to 39) |
| CPM response (%) (after treatment) | −3 (−12 to 9) | 17 (−2 to 36) | 15 (0–50)‡ | 0 (−1 to 23) |
| Change in CPM response (%) | −17 (−35 to −6) | 3 (−22 to 10) | 9 (4–55) | −7 (−35 to 16) |
Notes: All values are medians with IQRs. C5 is the C5 dermatome (lower neck), and T10V is the ventral T10 dermatome (upper abdominal area). Statistical difference between baseline and after treatment values:
*
P=0.009,
†
P=0.009, and
‡
P=0.006.
Abbreviations: CPM, conditioned pain modulation; ePDT, electric pain detection thresholds; IQR, interquartile range.