Multicenter prospective pilot study adding electroacupuncture for drug-refractory neuropathic pain

Objective: To test the effectiveness of electroacupuncture (EA) for managing intractable neuropathic pain (NeP) and assess the protocol for a larger confirmatory trial. Design: A prospective, multicenter, single-armed, add-on, pilot study. Settings/location: At two tertiary university-based hospitals in Seoul, Republic of Korea. Subjects: Patients with chronic peripheral NeP, who have received conventional oral medications but complained of moderate to severe pain. Interventions: Two Korean medicine doctors conducted 12 sessions of EA (2 sessions per week for 4 weeks, followed by 1 session per week for the second month) in addition to conventional treatment. Outcome measures: During the 8-week treatment period, pain intensity, pain natures such as burning, electric shock-like, temperature or mechanical hyperalgesia, and numbness, Short Form of the McGill Pain Questionnaire (SF-MPQ) and the Brief Pain Inventory (BPI-SF), the EuroQol five dimensions questionnaire, patients' satisfaction, and adverse events were evaluated. The primary endpoint was a change in pain intensity (%) at 4 weeks from the baseline. Results: Among 22 patients, 19 finished the protocol. The eight EA sessions over a month reduced pain intensity from 6.0&#x2009;&#xb1;&#x2009;1.6 at baseline to 3.2&#x2009;&#xb1;&#x2009;0.9 at 4 weeks, which was a 46.7% reduction (p&#x2009;<&#x2009;0.001). The incidences of severe burning, electric shock-like pain, and mechanical hyperalgesia reduced at 8 weeks [36%-16% (p&#x2009;=&#x2009;0.04), 53%-21% (p&#x2009;=&#x2009;0.009), and 53%-26% (p&#x2009;=&#x2009;0.03), respectively]. The affective dimensions in the SF-MPQ (p&#x2009;=&#x2009;0.007) and the pain interference parameters, including mood (p&#x2009;=&#x2009;0.02), relations with other people (p&#x2009;=&#x2009;0.03), and enjoyment of life (p&#x2009;=&#x2009;0.002) in the BPI-SF, were improved at 4 and 8 weeks. The majority of patients (68%) responded that their pain was "much or somewhat improved." Overall, 84.2% expressed "satisfaction" with their multidisciplinary management. Conclusions: EA might decrease the intensity of NeP, in particular, such as burning, electric shock-like pain, and mechanical hyperalgesia, which was accompanied by psychosocial and functional improvement. A larger study is warranted to prove the effectiveness of EA for managing refractory NeP. Trial registration: ClinicalTrials.gov: NCT03315598. Retrospectively registered on October 20, 2017.