Heat-sensitive Moxibustion as a Traditional Chinese Medicine Therapy for Chronic Obstructive Pulmonary Disease Combined with Insomnia

This protocol presents the clinical efficacy of heat-sensitive moxibustion in treating chronic obstructive pulmonary disease (COPD) combined with insomnia and outlines the procedure for heat-sensitive moxibustion.

Chronic Obstructive Pulmonary Disease (COPD) is a global health concern and a heterogeneous lung disease characterized by persistent, progressive airflow obstruction due to airway and/or alveolar abnormalities. COPD is associated with various comorbidities, including insomnia, which is a common underlying condition. Chronic insomnia exacerbates morbidity, increases hospitalization rates and healthcare costs, and reduces the quality of life in patients with COPD.

Heat-sensitive moxibustion is an emerging therapy that utilizes heat generated by ignited moxa materials. This technique involves suspending moxibustion over heat-sensitive acupoints to stimulate various sensations, such as heat penetration, expansion, transfer, local non-heat with distant heat, superficial non-heat with deep heat, and non-thermal sensations. These effects, along with meridian Qi conduction, enhance the therapeutic efficacy of moxibustion, making it a distinctive Chinese medicine therapy for insomnia. This study evaluated the efficacy of heat-sensitive moxibustion in patients with COPD and comorbid insomnia. The results demonstrated that heat-sensitive moxibustion significantly reduced Pittsburgh Sleep Quality Index (PSQI) and COPD Assessment Test (CAT) scores, indicating improvements in sleep quality and overall quality of life. Additionally, serum levels of interleukin-6 (IL-6) were decreased, while 5-hydroxytryptamine (5-HT) levels were increased, suggesting a potential mechanism underlying the observed therapeutic effects. This article provides a detailed protocol for standardizing the use of heat-sensitive moxibustion in the treatment of COPD with insomnia and presents clinical outcomes supporting its efficacy.

Chronic Obstructive Pulmonary Disease (COPD) is a significant global health concern. It is a heterogeneous lung disease characterized by persistent and progressive airflow obstruction due to abnormalities in the airways and/or alveoli. Clinical symptoms include coughing, sputum production, dyspnea, and chest tightness. The global prevalence of COPD among individuals aged 30-79 years has been reported to be 10.3%, with a prevalence of 8.6% in China^1,2.

COPD is frequently associated with comorbid conditions, including cardiovascular disease, osteoporosis, and pulmonary hypertension. The presence of comorbidities increases the risk of morbidity and mortality, leading to a higher likelihood of hospitalization and increased healthcare costs. Furthermore, comorbidities significantly impact the clinical status and prognosis of patients with COPD, complicating disease management^3,4.

Sleep disorders are a common consequence of COPD and often occur alongside nocturnal COPD symptoms, particularly cough and dyspnea. Studies indicate that approximately 40% of patients with COPD experience sleep disorders⁵, including obstructive sleep apnea (OSA), insomnia, and restless legs syndrome (RLS). The prevalence of OSA, RLS, and insomnia in patients with COPD has been reported to be 29.1%, 21.6%, and 29.5%, respectively⁶. The incidence of insomnia in patients with COPD is approximately three times higher than in the general population⁷. Additionally, hospitalized COPD patients experience an average reduction of 34 min of sleep per night and have a 22.5% lower probability of achieving normal sleep efficiency compared to those without COPD⁸.

A variety of traditional sedatives and hypnotics, including benzodiazepines, imidazopyridines, and, to a lesser extent, antidepressants, have been used to treat insomnia in COPD patients. While clinical trials suggest that these medications can be effective, their safety is not always assured^9,10.

Moxibustion has been shown to stimulate meridian Qi through heat and bioactive substances produced during combustion, thereby regulating physiological functions, treating diseases, and promoting overall health. Contemporary research suggests that the thermal stimulation from moxibustion plays a key role in disease treatment. The heat applied to the dermal level enhances blood flow, optimizes microcirculation, and facilitates vasodilation¹¹. Additionally, volatile oils released during the combustion of wormwood can have a calming effect on the brain, regulate neurotransmitter imbalances, and increase cerebral levels of 5-hydroxytryptamine (5-HT) and its metabolite, 5-hydroxyindoleacetic acid (5-HIAA)^12,13.

Heat-sensitive moxibustion is a novel therapeutic approach that differs from traditional moxibustion. It involves the application of moxa heat to heat-sensitive acupoints, offering notable benefits for the treatment of insomnia¹⁴. This article presents a demonstration of heat-sensitive moxibustion for treating insomnia in a patient with COPD.

The protocol was approved by the Ethics Committee of the Zigong First People's Hospital (No. Ethical (M) 2024-033). This was a before-and-after treatment controlled trial involving patients from the Hospital of Chengdu University of Traditional Chinese Medicine and the to Zigong First People's Hospital. Informed consent was obtained from all patients who participated in the study. The details of the reagents and equipment used are listed in the Table of Materials.

1. Patient assessment

1. Inclusion criteria
   1. Confirm that patients meet the diagnostic criteria for stable COPD outlined in the Global Strategy for the Prevention, Diagnosis, and Management of COPD¹⁵.
   2. Verify that patients meet the diagnostic criteria for COPD with lung and kidney qi deficiency in Chinese Medicine, as defined by the 2011 Guidelines for Chinese Medicine Diagnosis and Treatment of Chronic Obstructive Pulmonary Disease¹⁶. Diagnose COPD with lung and kidney qi deficiency if patients exhibit two primary symptoms and two secondary symptoms (Table 1).
   3. Ensure that patients meet either the diagnostic criteria for insomnia in Chinese adults¹⁷or the International Classification of Sleep Disorders (ICSD)¹⁸.
   4. Select patients aged 50-75 years, regardless of gender.
   5. Confirm that patients are conscious, mentally competent, and aware of the study.
2. Exclusion criteria
   1. Exclude patients with acute exacerbation of COPD.
   2. Exclude patients with COPD who do not have lung and kidney qi deficiency.
   3. Exclude pregnant women, children, and other patients for whom the procedure is not suitable.
   4. Exclude patients who refuse to undergo moxibustion treatment.
   5. Exclude patients who are allergic to medical devices (e.g., alcohol) or therapeutic drugs (moxa).
   6. Exclude patients with skin damage or sensory disorders at the treatment site.
   7. Exclude patients who have received acupuncture, sleeping pills, or treatment other than basic COPD therapy within the past 2 weeks.
      ​NOTE: The purpose of the patient assessment is to determine whether the patient is in a state suitable for moxibustion treatment.
3. Dropout criteria
   1. Withdraw subjects from the study if they meet any of the following criteria:
      1. Develop a serious adverse reaction during treatment.
      2. Voluntarily withdraw from the study.
      3. Experience a serious complication or disease progression during the study.
      4. Take other medications that may impact the final study results.

2. Study design

1. Use a comparative test method before and after treatment in the same patient. Observe patients (n = 12) with COPD complicated by insomnia of the lung and kidney qi deficiency type.
2. Provide all included patients with basic treatment for COPD, as outlined in the Global Strategy for the Prevention, Diagnosis, and Management of COPD¹⁵, including the following:
   1. Administer long-term oxygen therapy and ventilation support.
   2. Ensure that patients receive pharmacological interventions, including cough and sputum suppression and conventional anti-infective therapy with bronchodilators. Use β2-adrenergic (LABA), anti-muscarinic (LAMA) bronchodilators, and inhaled corticosteroids (ICS).
   3. Provide non-pharmacological interventions, including smoking cessation guidance, sleep education, and supervision of physical activities at an appropriate intensity.
3. Administer heat-sensitive moxibustion treatment to the patient.
4. Implement dietary interventions by instructing patients to avoid excitatory substances (e.g., strong tea), alcohol, and tobacco, and to refrain from overeating before bedtime.
5. Exclude other treatment modalities for sleep disorders to ensure the independence of the heat-sensitive moxibustion treatment.
6. Take emergency measures promptly in case of acute exacerbation of COPD during treatment. Record the acute exacerbation and treatment process in detail. After the condition improves, consult the patient and reassess to decide whether to continue the trial.
7. Withdraw patients from the study if no improvement is observed after 1 week of active treatment.

3. Pre-operation preparation

1. Material preparation
   1. Ensure the availability of the following items (Figure 1):
      1. Moxa sticks (long cylindrical strips rolled up with moxa floss as the main ingredient; general specifications: diameter: 16-40 mm) (Figure 1B).
      2. An ignition device, such as a lighter (Figure 1D).
      3. A surgical tray (length: 200 mm, width: 125 mm) (Figure 1A).
   2. Ensure medical swabs are within their validity period (Figure 1C).
   3. Obtain a portable infrared thermometer (Figure 1G).
   4. Provide tweezers and forceps as necessary (Figure 1E,F). No special requirements are needed, and they should be acceptable to all sterile healthcare personnel.
      NOTE: The category of ignition devices includes matches, alcohol lamps, and lighters. Select an appropriate device at the user's discretion. Use the ignition device to extinguish the flame promptly after use. Employ treatment discs to extinguish the fire of moxa sticks and remove ashes.
2. Environmental preparation
   1. Equip separate treatment rooms with smoke exhaust or elimination systems. Ensure that the surrounding environment is free of flammable substances to minimize fire hazards.
   2. Avoid using an oxygen supply device in the room to prevent the risk of combustion. Maintain the ambient temperature between 24-30 °C¹⁹.
3. Operator preparation
   1. Verify the patient's basic information. Wear a medical mask and a medical hat.
   2. Wash hands with soap and water using the seven-step handwashing method, and dry them thoroughly.
4. Patient preparation
   1. Skin cleansing
      1. Instruct the patient to cleanse the surgical area with water 2-3 times before the procedure to remove surface contaminants. Ensure that the cleaning radius exceeds 10 cm. Keep the skin dry after cleansing.
         NOTE: If conditions permit, use lukewarm water to enhance comfort during cleansing.
   2. Patient education and communication
      1. Educate the patient on moxibustion sensory expectations. Ensure the patient remains focused during moxibustion.
      2. Guide the patient to observe and report sensations such as warmth and penetration. Establish real-time communication between the practitioner and the patient.

4. Operating procedure

NOTE: Ensure that all practitioners involved in treatment delivery are certified acupuncturists with a minimum of one year of independent clinical experience. To ensure the accuracy and reproducibility of acupoint localization, all practitioners must complete a standardized training program before the study. This program should include (1) a comprehensive review of acupoint anatomy and localization techniques based on established textbooks, (2) hands-on practice sessions following a standardized protocol to ensure consistent technique application, and (3) a final assessment to confirm proficiency in acupoint identification. Additionally, a calibration test was conducted to evaluate inter-rater reliability, allowing only practitioners who achieved a Cohen's Kappa score of ≥0.8 to participate in the study. The treatment was conducted in accordance with the National Standard of the People's Republic of China for Technical Practice of Acupuncture and Moxibustion, Part 1: Moxibustion (GB/T 21709.1-2008)²⁰, and the Standardized Manipulations of Heat-sensitive Moxibustion Therapy²¹.

1. Patient positioning
   1. Instruct the patient to assume a prone position. Select positions based on acupoint topography to ensure optimal exposure.
2. Selection and positioning of acupuncture points
   1. Identify the following points in accordance with the Nomenclature and Location of Meridian Points (GB/T 12346-2021)²² (Figure 2): Xinshu (BL15), Danshu (BL19), Pishu (BL20), Feishu (BL13), Shenshu (BL23)^23,24,25.
      1. Xinshu (BL15): Locate on the back, under the spinous process of the 5^th thoracic vertebra, 1.5 cun from the posterior midline.
      2. Danshu (BL19): Locate on the back, under the spinous process of the 10^th thoracic vertebra, 1.5 cun from the posterior midline.
      3. Pishu (BL20): Locate on the back, below the spinous process of the 11^th thoracic vertebra, 1.5 cun from the posterior midline.
      4. Feishu (BL13): Locate on the back, below the spinous process of the 3^rd thoracic vertebra, 1.5 cun from the posterior midline.
      5. Shenshu (BL23): Locate on the back, below the spinous process of the 2^nd lumbar vertebra, 1.5 cun from the posterior midline.
3. Acupoint localization methods
   1. Use both the Bone-Length Measurement Method and the Finger-Cun Measurement Method²⁶ to determine acupoint locations.
      1. Apply the Bone-Length Measurement Method, which stipulates that the distance from the posterior midline to the inner edge of the scapula is 3 cun (Figure 2).
      2. Apply the Finger-Cun Measurement Method, where four fingers are aligned together, using the width of the patient's second knuckle as the standard, with the total transverse width of four fingers equating to 3 cun (Figure 3).
4. Heat-sensitive moxibustion procedure
   1. Thermal-sensitized acupoint positioning: Center the positioning on traditional acupoints (see step 4.2 and 4.3). Apply meridian moxibustion, gyratory moxibustion, sparrow-pecking moxibustion, and mild moxibustion to the upper, lower, left, and right areas of localized acupoints for heat-sensitized acupoint exploration.
      1. Ignite the moxa stick: Grip the moxa stick at its proximal third (top-middle segment). Ignite using a single-flame lighter at a 45° angle to ensure controlled combustion.
      2. Perform the following moxibustion techniques.
         1. Meridian moxibustion (Figure 4): Hold the moxa stick about 1/3 of the way up the middle and position the lit end perpendicularly above the meridian, 2-3 cm from the skin. Move the moxa stick at an even speed along the Foot Taiyang Bladder Meridian route for 2-3 min.
            NOTE: Repeat the process until the skin is warm and flushed without burning pain. Use a portable infrared thermometer to ensure a skin temperature of 41-42 °C²⁷. The Foot Taiyang Bladder Meridian runs from the head to the feet along the posterior body.
         2. Sparrow-pecking moxibustion (Figure 5): Hold the moxa stick about 1/3 of the way up the middle. Place the lit end perpendicularly above the acupuncture point, maintaining a 2-3 cm distance from the skin. Move the moxa stick in a vertical pecking motion, keeping a constant distance.
            NOTE: Ensure the skin is warm and flushed without causing burning pain. Use a portable infrared thermometer to confirm a skin temperature of 41-42 °C.
         3. Gyratory moxibustion (Figure 6): Hold the moxa stick about 1/3 of the way up the middle. Position the burning end perpendicularly above the acupuncture point, 2-3 cm from the skin. Rotate the moxa stick in a circular motion with a radius of 2.5 cm around the acupuncture point.
            NOTE: Ensure the skin is warm and flushed without burning pain. Use a portable infrared thermometer to confirm a skin temperature of 41-42 °C.
         4. Mild moxibustion (Figure 7): Hold the moxa stick about 1/3 of the way up the middle. Position the burning end perpendicularly 2-3 cm above the acupuncture point.
            NOTE: Ensure the skin is warm and flushed without burning pain. Use a portable infrared thermometer to confirm a skin temperature of 41-42 °C. Adjust the moxa stick's distance based on the patient's sensation. Use the index finger to assess temperature and prevent burns.
      3. Marking heat-sensitive acupoints: Maintain communication with the patient. Ask about sensations and identify thermal sensitization when the patient reports heat penetration, expansion, transmission, local non-heat with distant heat, superficial non-heat with deep heat, or any non-thermal sensations. Record the exact locations^28,29(Table 2).
      4. Selection of heat-sensitized acupoints : Select the two most distinctly felt acupoints for the next step.
         NOTE: Selection principle: (1) Prioritize heat-sensitive acupoints with non-heat sensations; (2) Prefer acupoints where heat-sensitive moxibustion sensation reaches the affected area; (3) Choose acupoints with the strongest heat-sensitive response³⁰.
   2. Double-point mild moxibustion (Figure 8)
      1. Confirm heat-sensitized acupoints. Hold the moxa stick about 1/3 of the way up the middle and ignite both simultaneously. Hold a moxa stick in each hand, directing them at the two selected acupoints, keeping a 2-3 cm distance from the skin.
         NOTE: Ensure the operation area is warm, with local skin flushing but no burning pain. Use a portable infrared thermometer to maintain a skin temperature of 41-42 °C.
      2. Continue moxibustion for 40 min^31,32.
5. Extinguishing the moxa stick and cleaning residues
   1. Place the burning end of the moxa stick into a water-filled treatment tray to extinguish the fire.
   2. Use pliers to remove large ash pieces. Wipe any remaining stains with gauze.
6. Treatment frequency: Administer treatment once every 2 days for 4 weeks.
7. Post-treatment care
   1. Instruct the patient to avoid touching or using cold water for 2 h.
   2. Keep the treated area at a comfortable temperature.
   3. Advise seeking medical attention if adverse symptoms occur.
      NOTE: Small blisters will naturally absorb. If large blisters form, puncture with a sterile syringe, apply antibiotic ointment, and keep the area clean to prevent infection.

5. Adverse event prevention and countermeasures

1. Preventive measures
   1. Prior to the study, ensure thorough communication with patients and their families, providing detailed explanations of the treatment rationale, procedures, and necessary precautions. This fosters cooperation and understanding.
   2. Adhere strictly to the prescribed surgical protocols. If the patient's condition worsens, terminate the trial and implement appropriate therapeutic measures. Adjust the treatment plan following the global strategy for the prevention, diagnosis, and management of COPD, reassessing the patient once their condition improves.
   3. Document all adverse reactions occurring during treatment, including burns, dermatological reactions, and severe pain.
2. Possible adverse events and countermeasures
   1. Burns: If a burn occurs due to prolonged or excessive heat exposure, immediately rinse the affected area with running cold water and apply a sterile gauze dressing or ointment. Seek medical attention if necessary.
   2. Skin rash: In case of a rash following moxibustion, apply an external anti-allergic ointment or administer oral anti-allergic medication as needed.
   3. Severe pain: If the patient experiences intense pain, stop the procedure immediately and immerse the affected area in cold water to relieve discomfort. If the pain persists or worsens, administer pain medication as required.

6. Efficacy evaluation

1. Primary outcome measures
   1. Assess treatment efficacy using the Pittsburgh Sleep Quality Index (PSQI)³³and the COPD Assessment Test (CAT)³⁴.
   2. Provide the PSQI questionnaire to patients 1 day before enrollment and 4 weeks after the treatment. Ensure that the total score is recorded, with higher scores indicating poorer sleep quality.
   3. Provide the CAT questionnaire before enrollment and after 4 weeks of the treatment. Record the total score, noting that higher scores indicate poorer quality of life.
      NOTE: Consider a ≥2-point reduction in CAT score as the Minimal Clinically Important Difference (MCID), indicating a clinically meaningful improvement³⁵.
2. Secondary outcome measures
   1. Collect blood samples from patients 1 day before enrollment and 4 weeks after the treatment.
   2. Measure serum levels of interleukin-6 (IL-6) and 5-hydroxytryptamine (5-HT) using enzyme-linked immunosorbent assay (ELISA). Record and analyze the results to evaluate changes in IL-6 and 5-HT levels after treatment³⁰.

7. Data statistics and analysis

1. Perform all statistical analyses using statistical analysis and graphing software.
2. Describe data measurements statistically using mean ± standard deviation.
3. Use paired t-tests to compare differences before and after treatment, as this is a stand-alone before-and-after control study.
4. Consider a p-value ≤0.05 as statistically significant for the tested differences.

This protocol outlines a before-and-after controlled trial investigating the efficacy of heat-sensitive moxibustion in improving sleep quality and overall quality of life in patients with COPD-related insomnia. A total of 12 patients (Table 3) diagnosed with COPD and insomnia were included in the study and received heat-sensitive moxibustion treatment.

Analysis of individual and total scores before and after treatment, including sleep quality, sleep latency, sleep duration, sleep efficiency, sleep disturbances, daytime dysfunction, and total PSQI scores, revealed a significant reduction in scores after treatment (P < 0.05). This suggests that heat-sensitive moxibustion effectively improves sleep quality (Table 4).

Regarding quality of life, a comparison of CAT total scores before and after treatment showed a significant decrease in CAT scores after treatment (P < 0.05), indicating that heat-sensitive moxibustion improves patients' overall quality of life (Table 5).

Additionally, serum analysis revealed that IL-6 expression levels were significantly lower after treatment, while 5-hydroxytryptamine levels were significantly higher compared to baseline (P < 0.05), further supporting the potential therapeutic effects of heat-sensitive moxibustion (Table 6).

Figure 1: Surgical equipment. (A) Surgical curved disc, (B) moxa sticks, (C) medical swabs, (D) lighter, (E) tweezers, (F) pliers, and (G) thermometer. Please click here to view a larger version of this figure.

Figure 2: Acupuncture Points and Localization. Diagram illustrating the locations of acupuncture points. Please click here to view a larger version of this figure.

Figure 3: Three-inch measurement chart. The second knuckle of the patient's finger is used to measure the transverse width of all four fingers, corresponding to a measurement of 3 cun. Please click here to view a larger version of this figure.

Figure 4: Meridian circulation moxibustion. The moxa stick is held about one-third of the way up and lit with a lighter. The lit end is positioned perpendicularly over the meridian, 2-3 cm from the skin. Moxibustion is applied at a steady speed along the meridian route, with each session lasting 2-3 min. The procedure is repeated until the skin appears flushed, accompanied by a sensation of warmth and heat. Please click here to view a larger version of this figure.

Figure 5: Sparrow pecking moxibustion. The moxa stick is held about one-third of the way up and lit with a lighter. The lit end is positioned vertically above the meridian, 2-3 cm from the skin. A vertical up-and-down movement, resembling a sparrow pecking, is used to apply moxibustion at a consistent rhythm. Please click here to view a larger version of this figure.

Figure 6: Circular moxibustion. The moxa stick is held about one-third of the way up and lit with a lighter. The lit end is positioned perpendicularly above the meridian, 2-3 cm from the skin. Moxibustion is applied by rotating the lit end of the moxa stick in a circular motion around the acupuncture point, with a radius of approximately 2.5 cm. Please click here to view a larger version of this figure.

Figure 7: Mild moxibustion. The moxa stick is held about one-third of the way up and lit with a lighter. The lit end is positioned perpendicularly to the meridian, 2-3 cm from the skin, and directed toward the acupuncture point to produce smoke at a consistent distance. Please click here to view a larger version of this figure.

Figure 8: Double-point gentle moxibustion. Gentle moxibustion is applied simultaneously to two heat-sensitive points. Please click here to view a larger version of this figure.

Table 1: Diagnostic criteria for Traditional Chinese Medicine differentiation of lung and kidney qi deficiency in patients with chronic obstructive pulmonary disease.

Table 2: Types and definition of thermal moxibustion sensation.

Table 3: Basic information of patients included in the study.

Table 4: Individual and Total Pittsburgh Sleep Quality Index (PSQI) scores before and after treatment. The PSQI scores of 12 patients were lower before treatment. A paired t-test was used for comparison before and after treatment, showing a statistically significant difference (P < 0.05). This result indicates an improvement in sleep quality following treatment, N = 12.

Table 5: COPD Assessment Test (CAT) scores before and after treatment. A comparison of CAT scores before and after treatment in 12 patients showed a decrease in scores. A paired t-test was used for self-controlled comparison, with results showing a statistically significant difference (P < 0.05), indicating an improvement in patients' quality of life, N = 12.

Table 6: Expression levels of IL-6 and 5-HT before and after treatment. The expression levels of IL-6 were decreased, while those of 5-HT were increased after treatment. A statistically significant difference was observed (P < 0.05), suggesting an improvement in sleep quality, N = 12.

Insomnia in patients with COPD can be attributed to several factors, including frequent awakenings due to hypoxemia and hypercapnia during sleep³⁶, nocturnal respiratory symptoms, and the use of COPD medications, which may affect sleep patterns. Additionally, anxiety and depression are significant contributors to insomnia. The prevalence of depression in COPD patients has been reported to be as high as 80%, while anxiety affects up to 74% of patients^37,38. Studies also indicate that over 20% of COPD patients are prescribed antidepressant medications³⁹.

The current pharmacological treatment for COPD-related insomnia primarily includes sedatives and antidepressants. However, these medications may have adverse effects on the respiratory system, including an increased risk of respiratory depression, respiratory failure, and mortality^40,41,42.

Feishu (BL13) belongs to the foot Taiyang bladder meridian and serves as the back-shu point of the lungs. It is a crucial acupoint for treating lung diseases, as it helps relieve cough, resolve phlegm, tonify lung qi, and regulate lung meridian qi. According to Classical Evidence and Treatment, the lungs govern qi, while the kidneys serve as its foundation. Traditional Chinese Medicine considers the pathogenesis of stable COPD to be closely related to dysfunction in the lungs, spleen, and kidneys. Data mining has identified BL13, BL20, and BL23 as core acupoints for treating stable COPD^23,24, and several clinical studies have demonstrated that stimulation of these points improves FEV1% in COPD patients^43,44.

In traditional Chinese Medicine (TCM), insomnia is classified as a disorder of both sleep and wakefulness and is frequently observed as a concomitant symptom of COPD. The TCM clinical guidelines of the Insomnia Research Group (WHO/WPO)⁴⁵ describe the pathogenesis of insomnia as resulting from disharmony between yin and yang, qi and blood, and disturbances in the five viscera. These imbalances lead to disruptions in mental stability and spiritual restlessness.

According to TCM theory, the five viscera -- the heart, liver, spleen, lungs, and kidneys -- are intricately linked to various physiological functions and mental activities. The acupoints Xinshu (BL15), Pishu (BL20), Feishu (BL13), and Shenshu (BL23) correspond to the dorsal acupoints of the heart, spleen, lungs, and kidneys, respectively. These back-shu points belong to the foot Taiyang bladder meridian and serve as external manifestations of the internal organs. Their stimulation can regulate visceral functions and enhance the body's vital energy (zheng qi). External TCM therapies targeting these acupoints have been shown to be effective in treating insomnia^46,47.

Additionally, the acupoint Danshu (BL19), located on the back, is associated with the gallbladder meridian. The gallbladder and heart meridians are interrelated and functionally coordinated, both playing key roles in mental regulation and qi circulation. TCM theory suggests that treating the heart and gallbladder in combination helps balance hippocampal monoamine neurotransmitters, including 5-hydroxytryptamine (5-HT), and promotes hippocampal cell repair²⁵. Therefore, moxibustion stimulation of Feishu, Xinshu, Danshu, Pishu, and Shenshu acupoints may enhance sleep quality and overall well-being in COPD patients.

Heat-sensitive moxibustion represents an innovative approach to moxibustion therapy, distinct from traditional techniques. This method, developed and refined by Professor Chen Rixin, is based on the clinical phenomenon of moxibustion-induced thermal sensitivity. Research indicates that in patients with diseases, the thermal sensitivity rate of acupoints is approximately 70%, significantly higher than the 10% observed in healthy individuals. Following recovery, the sensitivity rate declines to around 10%, suggesting a strong correlation between thermal sensitivity and disease states.

Professor Chen Rixin introduced the concept of "identification of sensitive moxibustion," emphasizing that clinical moxibustion should not only focus on selecting acupoints but also prioritize acupoints with heightened thermal sensitivity. This individualized approach tailors moxibustion treatment to each patient, aiming to eliminate heat-sensitive sensations and achieve the desired therapeutic desensitization⁴⁸. Clinical studies have demonstrated the efficacy of heat-sensitive moxibustion, highlighting its superiority over traditional moxibustion techniques⁴⁹. Previous research has shown that thermal moxibustion is effective in managing both insomnia and COPD^14,50,51.

Melatonin, a neurohormone crucial for maintaining circadian rhythms, is regulated by 5-hydroxytryptamine (5-HT), a neurotransmitter involved in sleep modulation^52,53. Studies have also indicated that sleep disorders are associated with elevated levels of interleukin-6 (IL-6)⁵⁴. The present study found that heat-sensitive moxibustion increased 5-HT levels while reducing IL-6 expression, suggesting its potential as an effective therapy for improving sleep in patients with COPD-related insomnia. As an external therapy in traditional Chinese medicine, heat-sensitive moxibustion leverages the unique principles of Chinese Medicine, offering a promising treatment approach for COPD patients with insomnia. However, as this study is a small sample, pre-post self-controlled, single-center trial, its objectivity may be limited. Future research should incorporate a larger sample size and include control groups to minimize bias and enhance the reliability of findings.

The authors have nothing to disclose.

This research was supported by the 2022 "Tianfu Qingcheng Plan" Tianfu Science and Technology Leading Talents Project (Chuan Qingcheng No. 1090) and Sichuan Science and Technology Program (2023ZYD0050). The authors would like to thank Mr. Yi Zhu for participating in our study as a model.