Quantitative sensory testing (QST) may not effectively discriminate between true and sham acupuncture treatment in patients with chronic pain despite the effectiveness of the intervention, according to study results published in Pain.
In this single-site randomized controlled trial, participants with chronic radicular back or neck pain (ie, described by patients as “shooting pain” in an upper or lower extremity; pain duration, ≥2 months; n=109) and healthy controls (n=95) were recruited. Patients were randomly assigned to receive no acupuncture (ie, routine care), true acupuncture, or sham acupuncture (for patients with chronic pain: n=30, 33, and 46, respectively), for a total of 6 sessions twice weekly. QST profiles, pain scores, and functionality profiles were assessed at baseline (visit 1) and after 3 (visit 4) or 6 sessions (visit 7).
True acupuncture was delivered at 3 Hz (pulse width, 70 microseconds, continuous mode, biphasic square wave) for 30 minutes. Sham needles preventing the penetration of the needle tip through the skin were used to conduct sham acupuncture while maintaining the motion of needle insertion.
No QST profile changes were detected in any of the three treatment groups in healthy controls or participants with chronic pain (likelihood ratio tests: heat-related QST, P =.533; cold-related QST, P =.549).
At visit 7, true acupuncture was found to reduce pain in participants with chronic back and neck pain (difference in mean, −1.0; 95% CI, −1.7 to −0.3; adjusted P =.021), improve physical functioning (difference in mean, 14.21; 95% CI, 5.84-22.58; adjusted P =.003), and improve energy/fatigue (difference in mean, −12.28; 95% CI, 3.46-21.11; adjusted P =.021) compared with routine care.
“Of note, this study was focused on immediate assessment at the end of a 3-week intervention (true acupuncture or sham acupuncture) or no intervention (routine care). As such, these results do not provide information on the duration of treatment effects (ie, long-term benefits) for study participants,” noted the researchers.
Chen L, Deng H, Houle T, et al. A randomized trial to assess the immediate impact of acupuncture on quantitative sensory testing, pain, and functional status [published online July 3, 2019]. Pain. doi:10.1097/j.pain.0000000000001651