Comparative effectiveness of different acupuncture courses for chronic insomnia disorder: a randomized controlled trial.

BACKGROUND

Acupuncture is effective for chronic insomnia disorder (CID), but the favorable treatment duration remains uncertain, and direct evidence comparing different treatment courses is limited. This study compared the effectiveness of 4-, 6-, and 8-week acupuncture courses to determine whether extending treatment provides additional clinical benefit.

METHODS

In this three-arm randomized controlled trial, 201 patients with CID were randomly assigned (1:1:1) to receive 4, 6, or 8 weeks of acupuncture (n = 67 per group), administered three times weekly using the same acupoints. The primary outcome was the the Insomnia Severity Index (ISI) score at treatment completion. Secondary outcomes included clinical remission (ISI < 8), and a minimal clinically important difference (ISI-MCID reduction ≥6), as well as scores on the Pittsburgh Sleep Quality Index (PSQI), Self-rating Depression Scale (SDS), Self-rating Anxiety Scale (SAS), and Fatigue Severity Scale (FSS), hypnotic medication use, and safety. Outcomes were assessed at baseline, treatment completion, and 1 and 3 months after treatment. Longitudinal continuous outcomes were analyzed using linear mixed-effects models under the intention-to-treat principle.

RESULTS

A total of 201 patients (157 women [78.1%], 44 men [21.9%]) were included in the intention-to-treat analysis. ISI scores decreased from baseline to post-treatment in the 4-, 6-, and 8-week groups, with mean changes of -7.4 points (95% CI, -9.0 to -5.8; P < .001), -9.7 points (95% CI, -11.4 to -8.0; P < .001), and -10.0 points (95% CI, -11.7 to -8.3; P < .001), respectively. Compared with the 4-week group, the 6- and 8-week groups showed greater improvements in ISI scores, with adjusted mean differences of -2.7 points (95% CI, -4.8 to -0.6; P = .008) and -2.8 points (95% CI, -4.9 to -0.6; P = .006), respectively. The additional improvement with the 8-week course versus the 6-week course was limited, with an adjusted mean difference of 0.0 points (95% CI, -2.2 to 2.1; P > .99). Clinical remission and MCID were more frequent in the 6-week group than in the 4-week group (P = .003 and P = .010, respectively). Sleep quality also generally favored the 6-week course over the 4-week course, with an adjusted mean difference of -1.9 points (95% CI, -3.6 to -0.2; P = .02). Between-group differences in depressive and anxiety symptoms were observed mainly between the 8- and 4-week groups. However, these secondary findings should be interpreted cautiously. No significant between-group differences were observed in fatigue or hypnotic medication use. No serious adverse events were reported.

CONCLUSION

Six- and 8-week acupuncture courses produced greater improvements in insomnia severity than a 4-week course in patients with CID. Extending treatment from 6 to 8 weeks provided limited additional benefit for core sleep outcomes. These findings may inform clinical decisions regarding acupuncture treatment duration for CID.

TRIAL REGISTRATION: https://www.chictr.org.cn [ChiCTR2300073711].