Effectiveness and cerebral responses of multi-points acupuncture for primary insomnia: a preliminary randomized clinical trial and fMRI study

Abstract

Background: Primary insomnia (PI) is characterized by difficulties in initiating sleep or maintaining sleep, which lead to many serious diseases. Acupuncture for PI has drawn attention with its effectiveness and safety. However, the operation of choosing acupoints lacks scientific suggestion. Our trial aims to provide reference and scientific basis for the selection of acupoints and to explore its possible mechanism.

Methods: A patient-assessor-blinded, randomized and sham controlled trial was designed to compare the efficacy of 5-weeks acupuncture at a single acupoint, the combination of multi-acupoints, and a sham point. The Pittsburgh sleep quality index and Athens Insomnia Scale questionnaire were used for the primary clinical outcomes, while polysomnography was performed for the secondary clinical outcomes. The resting state functional MRI was employed to detect the cerebral responses to acupuncture. The brain activity in resting state was measured by calculating the fractional amplitude of low-frequency fluctuations (fALFF), which reflected the idiopathic activity level of neurons in the resting state. These results were analyzed by two factorial ANOVA test and post-hoc t-tests.

Results: The clinical outcomes suggest that acupuncture could improve clinical symptoms, and the combination of multi-acupoints might lead to a better clinical efficacy. The rs-fMRI results suggested that the brain activity of certain regions was related to the sleep experience, and acupuncture could regulate the activity of these regions. Furthermore, the combination of multi-acupoints could impact more regions which were influenced by the sleep experience.

Conclusions: Acupuncture has been proven to be beneficial for PI patients, and the combination of multi-acupoints might improve its efficacy.

Trial registration: This trial has been registered on the U.S. National Library of Medicine (https://clinicaltrials.gov) ClinicalTrials.gov Identifier: NCT02448602 . Registered date: 14/04/2015.

Keywords: Acupuncture; Functional magnetic resonance imaging; Polysomnography; Primary insomnia.

Fig. 1

The location of the acupoints and diagrammatic sketch of the fMRI scan process. a The location of the acupoint in S-Acu group. a-c The location of acupoints in M-Acu group. d The location of the sham point in N-Acu group

Fig. 2

The brain regions with altered fALFF of S-Acu group after acupuncture treatment (P < 0.001, FWE correct P = 0.05, cluster size> 30). R: right brain. a: right cerebellum posterior lobe, b: left cerebellum posterior lobe, c: brainstem, d: right inferior temporal gyrus, e: left middle temporal gyrus, f: right parahippocampa gyrus, g: left precuneus, h: right superior frontal gyrus, k: left superior frontal gyrus. Colorbar refer to the increased fALFF value

Fig. 3

The brain regions with altered fALFF of M-Acu group after acupuncture treatment (P < 0.001, FWE correct P = 0.05, cluster size> 30). R: right brain. a: right cerebellum posterior lobe, b: left parahippocampa gyrus, c: left superior temporal gyrus and middle temporal gyrus, d: right superior temporal gyrus and middle temporal gyrus, e: left inferior frontal gyrus, f: left supramarginal gyrus, g: right precentral gyrus, h: right precuneus, k: left middle frontal gyrus, m: left postcentral gyrus. Colorbar refer to the increased fALFF value

Fig. 4

The brain regions with altered fALFF of N-Acu group after acupuncture treatment (P < 0.001, FWE correct P = 0.05, cluster size> 30). R: right brain. a: right superior frontal gyrus and medial frontal gyrus, b: left superior frontal gyrus, c: right middle frontal gyrus, d: left middle frontal gyrus, e: right inferior frontal gyrus. Colorbar refer to the increased fALFF value

Fig. 5

The distribution of brain regions where fALFF were negative correlation with AIS scores, and brain regions which were regulated by three acupuncture regimens. Colorbar refer to the increased fALFF value