TY - JOUR

T1 - Specifying the nonspecific components of acupuncture analgesia

AU - Vase, Lene

AU - Baram, Sara

AU - Takakura, Nobuari

AU - Yajima, Hiroyoshi

AU - Takayama, Miho

AU - Kaptchuk, Ted J.

AU - Schou, Søren

AU - Jensen, Troels Staehelin

AU - Zachariae, Robert

AU - Svensson, Peter

N1 - Copyright © 2013 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

PY - 2013

Y1 - 2013

N2 - It is well known that acupuncture has pain-relieving effects, but the contribution of specific and especially nonspecific factors to acupuncture analgesia is less clear. One hundred one patients who developed pain of ≥ 3 on a visual analog scale (VAS, 0 to 10) after third molar surgery were randomized to receive active acupuncture, placebo acupuncture, or no treatment for 30 min with acupuncture needles with potential for double-blinding. Patients' perception of the treatment (active or placebo) and expected pain levels (VAS) were assessed before and halfway through the treatment. Looking at actual treatment allocation, there was no specific effect of active acupuncture (P=.240), but there was a large and significant nonspecific effect of placebo acupuncture (P<.001), which increased over time. Interestingly, however, looking at perceived treatment allocation, there was a significant effect of acupuncture (P<.001), indicating that patients who believed they received active acupuncture had significantly lower pain levels than those who believed they received placebo acupuncture. Expected pain levels accounted for significant and progressively larger amounts of the variance in pain ratings after both active and placebo acupuncture (up to 69.8%). This is the first study to show that under optimized blinding conditions, nonspecific factors such as patients' perception of and expectations toward treatment are central to the efficacy of acupuncture analgesia and that these factors may contribute to self-reinforcing effects in acupuncture treatment. To obtain an effect of acupuncture in clinical practice, it may therefore be important to incorporate and optimize these factors.

AB - It is well known that acupuncture has pain-relieving effects, but the contribution of specific and especially nonspecific factors to acupuncture analgesia is less clear. One hundred one patients who developed pain of ≥ 3 on a visual analog scale (VAS, 0 to 10) after third molar surgery were randomized to receive active acupuncture, placebo acupuncture, or no treatment for 30 min with acupuncture needles with potential for double-blinding. Patients' perception of the treatment (active or placebo) and expected pain levels (VAS) were assessed before and halfway through the treatment. Looking at actual treatment allocation, there was no specific effect of active acupuncture (P=.240), but there was a large and significant nonspecific effect of placebo acupuncture (P<.001), which increased over time. Interestingly, however, looking at perceived treatment allocation, there was a significant effect of acupuncture (P<.001), indicating that patients who believed they received active acupuncture had significantly lower pain levels than those who believed they received placebo acupuncture. Expected pain levels accounted for significant and progressively larger amounts of the variance in pain ratings after both active and placebo acupuncture (up to 69.8%). This is the first study to show that under optimized blinding conditions, nonspecific factors such as patients' perception of and expectations toward treatment are central to the efficacy of acupuncture analgesia and that these factors may contribute to self-reinforcing effects in acupuncture treatment. To obtain an effect of acupuncture in clinical practice, it may therefore be important to incorporate and optimize these factors.

KW - Acupuncture Analgesia

KW - Acupuncture Points

KW - Analysis of Variance

KW - Anesthetics, Local/therapeutic use

KW - Double-Blind Method

KW - Female

KW - Humans

KW - Lidocaine/therapeutic use

KW - Male

KW - Pain Management

KW - Pain Measurement

KW - Pain, Postoperative/therapy

KW - Placebo Effect

KW - Regression Analysis

KW - Retrospective Studies

KW - Tooth, Impacted/surgery

U2 - 10.1016/j.pain.2013.05.008

DO - 10.1016/j.pain.2013.05.008

M3 - Journal article

C2 - 23707680

VL - 154

SP - 1659

EP - 1667

JO - Pain

JF - Pain

SN - 0304-3959

IS - 9

ER -