Effect of acupuncture and estazolam on episodic memory and sleep structure in patients with chronic insomnia disorder: a randomized controlled trial

Abstract

To compare the effect on chronic insomnia disorder (CID) and influences on episodic memory and sleep structure between acupuncture and estazolam tablets. A total of 140 CID patients were randomized into a meridian-point group (46 cases, 1 case dropped off), a non-meridian-and-non-acupoint group (47 cases, 2 cases dropped off) and a medication group (47 cases, 2 cases dropped off). In the meridian-point group, Baihui (GV 20), Shenmen (HT 7), Sanyinjiao (SP 6), Zhaohai (KI 6) and Shenmai (BL 62) were selected and the routine acupuncture was applied. In the non-meridian-and-non-acupoint group, the needling technique was same as the meridian-point group. Acupuncture was given once daily for 4 weeks in the above two groups. In the medication group, estazolam tablets were administered orally, taken 1 to 2 mg per night, consecutively for 4 weeks. Before and after treatment, the changes in the following indexes were observed in each group, i.e. the score of insomnia severity index (ISI), the score of auditory verbal memory test (AVMT) and the relevant indexes of sleep structure [total sleep time (TST), sleep onset latency (SOL), wake after sleep onset (WASO), sleep efficiency (SE) and the percentage of non rapid eye movement phase 1, 2 and 3 (N1, N2 and N3) and rapid eye movement time (REM) in TST]. After treatment, ISI scores were reduced in the meridian-point group and the medication group (P<0.01), the score in the meridian-point group was lower than the medication group and the non-meridian-and-non- acupoint group respectively (P<0.01) and that in the medication group was lower than the non-meridian-and-non-acupoint group (P<0.01). After treatment, the score of each of immediate recall, short-term delayed recall, long-term delayed recall and delayed recognition of AVMT was increased in the meridian-point group and the medication group respectively (P<0.01, P<0.05) and the score of each item of AVMT in the meridian-point group was higher than the medication group and the non-meridian-and-non-acupoint group respectively (P<0.01, P<0.05). The scores of immediate memory and delayed recognition in the medication group were higher than the non-meridian-and-non-acupoint group respectively (P<0.01). After treatment, SOL, WASO and N1% were all reduced (P<0.01) and TST, SE, N3% and REM% were all increased (P<0.01, P<0.05) in the meridian-point group and the medication group, N2% in the meridian-point group was reduced (P<0.01). After treatment, N1% and N2% in the meridian-point group were lower than the medication group (P<0.01) and N3% and REM% were higher than the medication group (P<0.01). After treatment, TST, SE and N3% in the meridian-point group and the medication group were all higher than the non-meridian-and-non-acupoint group respectively (P<0.01, P<0.05) and SOL, WASO and N1% were lower than the non-meridian-and-non-acupoint group respectively (P<0.01). REM% in the meridian-point group was also higher than the non-meridion-and-non-acupoint group (P<0.01), and N2% in the meridian-point group was also lower than the non-meridian-and-non-acupoint group (P<0.01). Compared with estazolam, acupuncture much better improves sleep quality and episodic memory in patients with chronic insomnia disorder, which is possibly related to the regulation of sleep structure of patients in treatment with acupuncture.