Electroacupuncture for Insomnia in Patients With Chronic Sciatica Due to Lumbar Disc Herniation: a Randomized Controlled Trial

• Electroacupuncture (Procedure): Electroacupuncture will be administered by a licensed acupuncturist. Adhesive foam pads will be applied at each acupoint to enhance blinding. Sterile needles will be inserted through the pads into the skin at predefined acupoints, including Sishencong (EX-HN1), bilateral Shenmen (HT7) and Sanyinjiao (SP6), Jiaji (EX-B2) at the L3-L5 levels (bilateral points at each segment), Shenshu (BL23), Dachangshu (BL25), and selected lower limb acupoints. Electrical stimulation will be applied using a sparse-dense wave (2/10 Hz) for 30 minutes per session. Treatment will be delivered three times per week for four weeks.
• Sham electroacupuncture (Procedure): Sham electroacupuncture will be administered by a licensed acupuncturist. Adhesive foam pads will be applied at each non-acupoint to maintain blinding. Sterile needles will be inserted superficially (2-3 mm) through the pads without manipulation or eliciting deqi sensation. Electrical stimulation will be minimally applied only briefly at the beginning and end of each session to mimic the procedure. Treatment duration and frequency will be identical to the electroacupuncture group (30 minutes per session, three times per week for four weeks).

Primary outcomes

• Pittsburgh Sleep Quality Index (PSQI) total score [Week 4]: The Pittsburgh Sleep Quality Index (PSQI) is a validated self-reported instrument designed to assess sleep quality over the preceding month, with total scores ranging from 0 to 21, where higher scores denote poorer sleep quality.

Secondary outcomes

• Numerical Rating Scale (NRS) score for leg pain intensity [Baseline, Week 2, Week 4, and Week 8]: The 11-point Numerical Rating Scale (NRS) is a self-reported instrument used to assess average radiating leg pain intensity over the preceding 24 hours, with scores ranging from 0 to 10, where higher scores denote more severe pain.
• Numerical Rating Scale (NRS) score for low back pain intensity [Baseline, Week 4, and Week 8]: The 11-point Numerical Rating Scale (NRS) is a self-reported instrument used to assess average low back pain intensity over the preceding 24 hours, with scores ranging from 0 to 10, where higher scores denote more severe pain.
• Oswestry Disability Index (ODI) score [Baseline, Week 4, and Week 8]: The Oswestry Disability Index (ODI) is a self-reported questionnaire used to assess disability related to lumbar spine disorders, with percentage scores ranging from 0% to 100%, where higher scores denote greater disability.
• Insomnia Severity Index (ISI) score [Baseline, Week 2, Week 4, and Week 8]: The Insomnia Severity Index (ISI) is a self-reported instrument used to assess the subjective severity of insomnia, its impact on daytime functioning, and associated distress over the preceding two weeks, with total scores ranging from 0 to 28, where higher scores denote more severe insomnia.
• Pittsburgh Sleep Quality Index (PSQI) total score [Week 8]: The Pittsburgh Sleep Quality Index (PSQI) is a validated self-reported instrument designed to assess sleep quality over the preceding month, with total scores ranging from 0 to 21, where higher scores denote poorer sleep quality.
• Proportion of participants achieving ≥50% reduction in Pittsburgh Sleep Quality Index (PSQI) total score [Week 4, Week 8]: The Pittsburgh Sleep Quality Index (PSQI) is a validated self-reported instrument designed to assess sleep quality over the preceding month, with total scores ranging from 0 to 21, where higher scores denote poorer sleep quality.
• Sleep efficiency measured by actigraphy [Baseline, Week 4]
• Total sleep time measured by actigraphy [Baseline, Week 4]
• Incidence of adverse events [From baseline to Week 8]

Other outcomes

• Resting-state electroencephalography-derived microstate parameters [Baseline, Week 4]: Resting-state electroencephalography-derived microstate parameters, including mean duration, occurrence rate, time coverage, and transition probability, will be assessed at baseline and week 4. Mean duration refers to the average time for which a microstate class remains stable; occurrence rate refers to the number of occurrences per second; time coverage refers to the percentage of total recording time occupied by a microstate class; and transition probability refers to the probability of transition from one microstate class to another.
• Untargeted plasma metabolomic features [Baseline, Week 4]: Fasting plasma samples will be collected at baseline and week 4 and analyzed using an untargeted metabolomics approach based on ultra-high-performance liquid chromatography-high-resolution mass spectrometry (UHPLC-HRMS). Detected metabolomic features will be characterized by mass-to-charge ratio, retention time, relative ion intensity, and tandem mass spectrometry spectra.
• Credibility/Expectancy Questionnaire scores [Baseline]: Treatment credibility and expectancy will be assessed before treatment using the Credibility/Expectancy Questionnaire. The credibility subscale consists of three items rated on a 1-9 scale, with a total score ranging from 3 to 27; higher scores indicate greater perceived treatment credibility. The expectancy subscale consists of three items assessing expected improvement and perceived treatment benefit. Two items are rated from 0% to 100%, and one item rated on a 1-9 scale will be transformed to a 0-100 scale; the three items will be averaged to generate a score ranging from 0 to 100, with higher scores indicating greater treatment expectancy.
• Bang blinding index [Week 4]: At week 4, before unblinding, participants will complete a structured blinding assessment question asking them to guess their treatment allocation as real electroacupuncture, sham electroacupuncture, or "uncertain." Blinding success will be quantified using the Bang blinding index and its 95% confidence interval. The Bang blinding index ranges from -1 to 1, with values close to 0 indicating successful blinding. Values between -0.2 and 0.2 will be interpreted as indicating adequate blinding.

Sex: All, ages: 18 Years to 75 Years

Inclusion Criteria:

Participants will be eligible if they meet all of the following criteria:

1. Aged 18-75 years, of either sex;
2. Diagnosis with lumbar disc herniation accompanied by unilateral chronic sciatica (disease duration ≥ 3 months);
3. Experiencing moderate to severe radiating leg pain (below the knee), defined as a Numerical Rating Scale (NRS) score ≥ 4 at screening within the past 24 h;
4. Diagnosis of chronic insomnia, with a Pittsburgh Sleep Quality Index (PSQI) total score > 7;
5. Onset or exacerbation of insomnia temporally associated with the onset or worsening of sciatica symptoms;
6. Willing to participate and able to provide written informed consent.

Exclusion Criteria:

Participants will be excluded if any of the following criteria are met:

1. Spinal or structural conditions: lumbar spinal stenosis, spondylolisthesis, vertebral fracture, spinal infection (e.g., tuberculosis), or tumor;
2. Surgical indications: cauda equina syndrome, conus medullaris syndrome, or other conditions requiring urgent surgical intervention;
3. Severe systemic diseases: unstable cardiovascular, hepatic, renal, respiratory, or hematological disorders, or metabolic conditions that may significantly affect study outcomes (e.g., uncontrolled diabetes or thyroid disease);
4. Neurological or psychiatric disorders: major neurological diseases (e.g., epilepsy, Parkinson's disease, dementia, multiple sclerosis) or severe psychiatric disorders (e.g., schizophrenia);
5. Clinically significant depression or anxiety, defined as Patient Health Questionnaire-9 (PHQ-9) ≥ 10 and/or Generalized Anxiety Disorder-7 (GAD-7) ≥ 10;
6. Other primary sleep disorders, including obstructive sleep apnea, narcolepsy, or restless legs syndrome;
7. Use of centrally acting medications: regular use (≥ 3 days/week within 4 weeks prior to enrolment) of medications affecting the central nervous system (e.g., opioids, sedative-hypnotics, antidepressants) without an adequate washout period (≥ 2 weeks or longer depending on drug half-life);
8. Irregular sleep patterns, including night shift work (≥ 2 times/week between 22:00-06:00) or highly irregular sleep-wake cycles;
9. Pregnancy or lactation;
10. History of substance abuse or dependence;
11. Lumbar spine surgery or interventional procedures within the past 3 months;
12. History of acupuncture treatment;
13. Implanted electronic devices (e.g., pacemakers) or metal implants at acupuncture sites;
14. Participation in another clinical trial within the past 3 months;
15. Severe sensory or cognitive impairment affecting assessment compliance;
16. Any other condition deemed by investigators to compromise safety or data integrity.