A Randomized Clinical Trial
Cong Wang, Wen-lin Xu, [...], and Yun-fei Chen
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I. Introduction
The research paper titled "Impact of Acupuncture on Sleep and Comorbid Symptoms for Chronic Insomnia: A Randomized Clinical Trial" aims to evaluate the efficacy and safety of acupuncture in treating chronic insomnia. Chronic insomnia is a prevalent and debilitating condition that affects individuals' quality of life and is often accompanied by comorbid symptoms such as anxiety and depression.
The main research question of this study is whether acupuncture at specific acupoints can improve sleep and alleviate comorbid symptoms in patients with chronic insomnia.
II. Methodology
The study utilized a randomized, single-blind, parallel, and sham-controlled trial design. A total of 82 participants with chronic insomnia were randomly assigned to either an acupuncture group (n = 41) or a sham acupuncture group (n = 41). The acupuncture treatment involved 10 sessions over a period of 3 weeks at bilateral HT 7 and KI 7 acupoints, while the sham acupuncture group received shallow needling at non-specific points.
Data collection included subjective assessments such as the Pittsburgh Sleep Quality Index (PSQI), the Insomnia Severity Index (ISI), and various comorbid symptom scales. Polysomnography (PSG) was used to measure objective sleep parameters. Data analysis involved comparing the outcomes between the acupuncture group and the sham acupuncture group.
However, it is important to note that there may be limitations or assumptions associated with the study, which should be taken into consideration.
III. Results
The key findings of the research indicate that acupuncture at HT 7 and KI 7 acupoints significantly improved sleep quality and reduced insomnia severity in patients with chronic insomnia. The acupuncture group showed a greater decrease in PSQI and ISI scores compared to the sham acupuncture group. The acupuncture group also demonstrated improved objective sleep parameters, including reduced sleep onset latency and increased percentage of sleep stage N3.
While both the acupuncture and sham acupuncture groups experienced reductions in comorbid symptoms, there were no significant differences observed between the groups in these secondary outcome measures.
Relevant statistical analyses were conducted to compare the treatment outcomes between the acupuncture group and the sham acupuncture group.
IV. Discussion
In relation to the research question and objectives, the results of the study suggest that acupuncture at HT 7 and KI 7 acupoints is an effective and safe nonpharmacological intervention for chronic insomnia. The findings highlight the potential of acupuncture as a complementary therapy for improving sleep quality and reducing insomnia severity.
The implications of the study's findings include the addition of a viable treatment option for chronic insomnia, particularly for individuals who may prefer nonpharmacological approaches or who experience side effects from pharmacologic treatments. The significance lies in the comprehensive evaluation of acupuncture's impact on both subjective and objective sleep measures, shedding light on its potential as a holistic intervention.
However, it is important to acknowledge the limitations of this study, such as the small sample size and the use of a single-blind design. Further research with larger sample sizes and longer follow-up periods is needed to strengthen the evidence and explore the long-term effects of acupuncture on chronic insomnia.
V. Conclusion
In conclusion, this research paper provides evidence supporting the efficacy and safety of acupuncture at HT 7 and KI 7 acupoints for improving sleep and reducing insomnia severity in patients with chronic insomnia. The findings contribute to the field by emphasizing the potential of acupuncture as a nonpharmacological intervention option for chronic insomnia.
Further research is warranted to address the limitations of this study and to investigate the optimal treatment plan and mechanisms of acupuncture for chronic insomnia. Overall, this study demonstrates the value of acupuncture in addressing the multifaceted nature of chronic insomnia and its comorbid symptoms.
Acupoints for the acupuncture and sham acupuncture groups.
Measures
Primary Outcome Measures
Pittsburgh Sleep Quality Index (PSQI): The PSQI contains 19 self-assessed items and 5 other-rated items. The self-assessed items evaluate duration of sleep, sleep onset latency, sleep efficiency, sleep disturbance, need for medications to sleep, daytime dysfunction, and overall sleep quality. The total score is 0–21. A higher score indicates a worse quality of sleep.35 The PSQI is widely used to evaluate sleep dysfunction,47 and it is more inclined to evaluate the subject’s sleep state during the workday.48 A total score >5 indicates that the subjects have poor sleep quality and has significance for clinical treatment.49 The Chinese version of the PSQI has high reliability and validity for the Chinese population and has been used as an effective tool for sleep screening in clinical and scientific research.50,51 This study evaluated the PSQI at baseline, posttreatment, one-week follow-up and one-month follow-up.
Insomnia Severity Scale (ISI): The ISI mainly evaluates the nature and severity of insomnia and its impact on daytime function. The scale consists of 7 evaluation items, and the total score ranges from 0–28 points. A higher score indicates more severe insomnia.52 The ISI is mainly used to screen for insomnia and to evaluate treatment effects in clinical research.53 A total score of 8–14 indicates subclinical insomnia, and a total score >14 indicates clinically significant insomnia. A reduction in the ISI score by 8 points or more reflects a significant treatment effect in clinical evaluations. ISI has good reliability and validity.54 The Chinese version has high reliability and validity for evaluating insomnia among the Chinese population.55 This study evaluated ISI at baseline, posttreatment, one-week follow-up and one-month follow-up.
Secondary Outcome Measures
Polysomnography (PSG): PSG was used as the objective sleep evaluation index. The PSG (NIHON KOHDEN, Japan) used in this study was composed of multiple quantitative parameters. The collection indicators included electroencephalogram (EEG), mentalis electromyography (EMG), bilateral electrooculography (ECoG), oral/nasal airflow, and bilateral anterior tibial EMG. In this study, PSG was used for two consecutive nights to eliminate the “first night effect”.56 PSG monitoring started from the usual bedtime to the next morning, and a total of 8.0 hours were recorded. The efficacy evaluation of this study was based on EEG. The sleep stages and parameters were manually scored based on the American Academy of Sleep Medicine Manual for the Scoring of Sleep and Associated Events.57 The objective sleep evaluation parameters used in this study included the following: total sleep duration (TST); sleep onset latency (lights out to first epoch of any sleep, SOL); REM sleep latency (REM-sl); wake after sleep onset (WASO, SOL minus TST); sleep efficiency (SE, TST/total recording time × 100%); arousal index (Arl; number of arousals ×60/TST); and percent time in each stage (length of each sleep stage/TST×100%). In this study, during the screening period and at posttreatment, two consecutive monitorings were performed, but only the second result for each timepoint was used as the efficacy evaluation index.
Beck Anxiety Inventory (BAI): The BAI was developed by Beck et al in 198858 and contains a total of 21 anxiety symptom items. It has been used as an evaluation index to evaluate the anxiety state of the subject within the past week. Higher scores correspond to more serious anxiety. Generally, BAI≥45 is used as the criterion to indicate anxiety. The scale is simple in content, easy to administer, and easily understood. The Chinese version has good reliability and validity and is commonly used for the evaluation of anxiety symptoms in China.59,60 This study evaluated it at baseline and posttreatment.
Beck Depression Inventory (BDI): The BDI was developed by Beck et al according to the diagnostic criteria for depression in the DSM-IV.61 Beck et al formulated the first version of the BDI in 1961 and restructured it for the second version, which is now generally used. The BDI has a total of 21 self-evaluated depression-related items that can evaluate depression in the past 7 days. The higher the total score, the more severe the depression. A total score of 0–13 indicates no depression, 14–19 indicates mild depression, and 29–63 indicates severe depression. The Chinese version of the BDI has good validity and reliability.62,63 This study evaluated it at baseline and posttreatment.
Fatigue Severity Scale (FSS): FSS was proposed and formulated by Krupp et al in 1989.64 The FSS scale is simple and clear. It consists of only 9 self-evaluation items. Subjects scored themselves on the corresponding symptoms. Higher total scores indicate more fatigue. Studies have shown that the FSS score of patients with insomnia is higher than 5.5, which means that there is a high level of daytime fatigue among patients with insomnia.65 The Chinese version of the FSS has good validity and reliability.66 This study evaluated the FSS at baseline and posttreatment.
Epworth Sleepiness Scale (ESS): The ESS is a relatively simple and internationally recognized sleepiness assessment scale.67 It has a total score of 24 points. The higher the score is, the more severe the daytime sleepiness. This scale is generally used to screen and evaluate the hypopnea status of patients with obstructive sleep apnoea-hypopnea syndrome (OSAHS), but studies have shown that the ESS scale can be used to screen and diagnose other sleep disorders.68 The Chinese version of the ESS has good validity and reliability.69 This study used the ESS to assess the daytime sleepiness of subjects at baseline and posttreatment.
Safety Assessments
Two types of safety assessments were performed: evaluation of changes in routine blood tests, liver function, and kidney function after the 10 intervention sessions and records of adverse events during the entire study. The record of adverse events in this study was conducted using the Adverse Event Record Form. Subjects were required to fill in the list of adverse events during the study, including the time point, severity, measures taken, whether the event was related to the treatment and prognosis. During the assessment phase, researchers assessed the possible relationship between adverse events and the study treatment, as well as medications taken concurrently. Adverse events include all adverse reactions that are definitely related to treatment, most likely related to treatment, and likely related to treatment.
Sample Size
The required sample size was estimated based on the change in PSQI scores. According to previous research by our team,21 sham acupuncture can reduce the PSQI to 14.76 after 10 interventions, with an SD of 3.35. This study hypothesized that acupuncture at HT 7 and KI 7 for insomnia would reduce the PSQI by 2.70 points more than sham acupuncture. According to the needs of this study, we made α=0.05 and 1-β=0.90, according to the formula:70
A two-sided test was performed. Through the query, =1.96, =1.282, and calculated n=33.32≈34. In addition, considering the loss factor (according to a 20% loss rate), the final sample size was 41 subjects in each group, for 82 subjects in total.
Randomization and Blinding
Specialized statisticians who were independent of the research group generated 82 random numbers in SPSS 25.0 and then arranged these numbers in order from small to large. Numbers 1–41 were artificially specified as the acupuncture group, and 42–82 were specified as the sham acupuncture group. The random numbers are reproducible (random seed number: 20190520). Subjects entered the acupuncture group or the sham acupuncture group according to randomly assigned numbers at a ratio of 1:1 after signing the informed consent form. The random number and treatment plan corresponding to each subject were printed on a card and stored in an opaque envelope. Each subject who signed the informed consent form was given an envelope with their name, which was handed over to the acupuncturist during the treatment. The acupuncturist checked the envelope and removed the treatment card to view the treatment plan.
During the study, the generation of the random numbers list, subject recruitment, acupuncture treatment, outcome measure assessment and follow-up were performed independently by different researchers. Only the outside assistant and the acupuncturist were aware of the allocation. Participants and other relevant researchers were blinded to the allocation.
Statistical Analysis
The statistics and analysis of all data were performed by two analytical researchers independent of the trial. Intention-to-treat (ITT) was used as the evaluation method to evaluate the results of the study. Statistical analysis of the data was performed using SPSS 25.0. The measurement data conformed to a normal distribution, and homogeneous variances were determined using the mean ± standard deviation to describe the central tendency and the degree of dispersion. The primary outcome assessments were analysed using a mixed-effect model for repeated measures (MMRM) with patients as a random-effect factor, treatment group, age, gender, time and comorbidities as the fixed variable, patients as the random variable, random effects including intercept, baseline as a covariable, age*group, gender*group, time*group and comorbidities*group as interaction effect using a first-order ante dependence covariance matrix. The comparison between groups used the independent sample t test, and the comparison of multiple time points within groups used repeated measurement data combined with multivariate variance analysis. For measurement data that did not conform to the normal distribution, the median, minimum, and maximum were given. The between-group comparisons used the Mann–Whitney U-test, and the within-group comparisons used the Friedman (F) test. Enumeration data were expressed as frequency and composition rate. For binary or multicategory nonranked data, comparisons between groups were performed by the χ2 test. If the data were ranked as ordinal data, the comparison between groups was performed by the Mann–Whitney U-test.
All statistical analyses used two-sided tests, and P values of ≤.05 were considered statistically significant.
Results
Subject Characteristics
A total of 91 subjects were recruited, of whom 9 were excluded during screening. Eighty-two subjects with chronic insomnia meeting the criteria were included in this study and were randomly assigned to the acupuncture group or the sham acupuncture group. Among the subjects, 4 withdrew for personal reasons; 1 withdrew due to poor results; 1 withdrew due to adverse reactions; and 1 completed the treatment but did not undergo posttreatment evaluation. Therefore, a total of 75 eligible subjects completed the treatment and follow-up stage, including 37 in the acupuncture group and 38 in the sham acupuncture group (Figure 2).
Flow of subjects randomized to acupuncture or sham acupuncture.
Table 1 presents the demographic characteristics of the subjects. Subjects’ ages ranged from 25 to 73 (median 58 years), 23 (28.0%) were male, and 59 (72.0%) were female. The majority of the subjects were normal weight (n = 68, 82.9%). The subjects had a longer course of insomnia (median 9.5 years). Approximately 53.7% of the subjects were taking sedative-hypnotic drugs. There were no differences in the demographics between the two groups. Baseline clinical characteristics were also balanced between the two groups (Tables 2 and and33).
Demographic Characteristics of Subjects
The Mixed Effect Model Analysis of Primary Outcome Measures
Primary Outcome Measures from Baseline to 4-Week Follow-Up
Efficacy
Primary Outcome Assessments
The mixed-effect model analysis revealed that there were significant effects for the time × treatment interaction on the PSQI (F=4.756, P=0.004) (Table 2 and Figure 3), which means that the change trend of the PSQI over time was different due to the different groups. The mixed-effect model analysis also showed significant effects for the time × treatment interaction on the ISI (F=4.130, P=0.008) (Table 2 and Figure 4), which means that the change trend of the ISI over time was different due to different groups. There were improvements in PSQI and ISI scores after either acupuncture or sham acupuncture treatment (Table 3). PSQI scores decreased from 14.78 to 9.74 in the acupuncture group and from 14.61 to 11.69 in the sham acupuncture group. After treatment, the difference between groups was statistically significant (F=−2.537, P=0.013). ISI scores at baseline were 18.78 for the acupuncture group and 20.49 for the sham acupuncture group. The scores decreased to 11.13 for the acupuncture group and 15.44 for the sham acupuncture group. After treatment, the difference between groups was statistically significant (F=−3.796, P<0.001). Although the PSQI and ISI scores were lower than at baseline at the one-week follow-up and one-month follow-up, no differences were observed between groups (P>0.05 for all comparisons).
Mean PSQI scores of the two groups during the study period.
Mean ISI scores of the two groups during the study period.
Secondary Outcome Assessments
PSG Assessments
The results of PSG measurements are summarized in Table 4. After treatment, there were significantly lower levels of SOL [15.5 (10.0, 18.5) vs 18.5 (11.5, 31.0), P = 0.039) in the acupuncture group than in the sham acupuncture group. In terms of sleep architecture, the percentage of sleep stage N1 (19.65±5.06% vs 24.99±4.60%, P = 0.015) was decreased and that of stage N3 (25.22±5.31 vs 17.88±4.84, P = 0.002) was increased significantly in the acupuncture group compared with the sham acupuncture group. However, no significant differences in the percentage of stages N2 or R were noted between the groups (P > 0.05).
PSG Measures from Baseline to Post-Treatment
Assessment of Comorbid Symptoms
The results of comorbid symptom assessments are summarized in Table 5. After treatment, there were lower levels of comorbid symptoms (BAI, BDI, FSS and ESS) in both the acupuncture group and the sham acupuncture group. However, no significant differences were noted between the groups after treatment (P > 0.05).
Comorbid Symptom Measurements from Baseline to Post-Treatment
Safety Assessments
The main observation and recording indicators in this study were WBC, RBC, Hb, and PLT as routine blood tests; AST, ALT, and ALP for liver function; and UREA, CRE, and UA for kidney function. The blood indicators of the subjects were divided into three levels: normal range, abnormalities with no clinical significance, and abnormalities with clinical significance. The results showed that the blood indicators of the two groups had no abnormal changes from baseline to posttreatment.
During the implementation of this study, one subject in the sham acupuncture group withdrew due to foot swelling. The research leader judged that the relationship with intervention was “may not be relevant”. Some subjects experienced local subcutaneous bleeding symptoms after the needles were removed, but the bleeding time did not exceed 1 minute, and there was no other discomfort. During the study period, no subjects experienced adverse reactions such as needle syncope, needle sticking, or subcutaneous haematoma, and no subjects experienced pain for longer than 30 minutes due to the intervention.
Discussion
This study is consistent with our team’s previous research21 and other similar clinical studies of acupuncture for insomnia.18,71,72 The current study found that acupuncture can improve subjective and objective sleep indicators in patients with chronic insomnia. To the best of our knowledge, this is the first study to evaluate the efficacy and safety of using acupuncture at HT 7 and KI 7 to improve sleep and comorbid symptoms in chronic insomnia through subjective and objective measurements. On the basis of our previous research,21 we reduced the pain of subjects by streamlining the acupoints, improved compliance (drop-out rate 8.54%), introduced more efficacy evaluation indicators, and extended the follow-ups to one month.
This study used the PSQI and ISI as the main outcome measures. We found that in the acupuncture group, PSQI and ISI scores decreased by 5.04 and 7.65 points, respectively, after 10 sessions of acupuncture treatment. Similarly, improvements were also found in other studies of acupuncture for insomnia.18,21 Previous research by our team has shown that for patients with perimenopausal insomnia, 10 sessions of acupuncture significantly reduced PSQI and ISI scores by 8.03 and 11.35 points, respectively. This study did not achieve the same effect. The reasons may be as follows: First, the acupoints were simplified in this study, and the effect of the treatment was reduced accordingly. Second, the previous study was aimed at people with perimenopausal insomnia, and appropriate acupoints can reduce perimenopausal symptoms and indirectly improve sleep symptoms. Third, compared with the previous study, the subjects recruited in this study had a lower severity of insomnia at the baseline analysis. In addition, there are some clinical studies on acupuncture for insomnia that have not achieved such a significant effect in subjective measurements. Xua Yin and colleagues18 found that the ISI score decreased 6.6 points after 4 weeks of acupuncture among subjects with insomnia. The study by Wing-Fai Yeung et al39 found no significant differences between groups in ISI or other outcome measures. The inconsistencies may be caused by differences in the choice of acupuncture points (number and attributes), acupuncture manipulation, and study populations. In this study, we provided direct evidence for the benefits of acupuncture at HT 7 and KI 7 in treating chronic insomnia among the Chinese population.
Among the factors that could affect acupuncture treatment for insomnia, the selection of acupoints is the most important. According to TCM theory, the selection for acupoints is based on three main strategies, ie, acupoints of the corresponding meridian, experience points, and special acupoint combinations. Therefore, each clinical study has different acupuncture point selections according to different TCM theories. In previous studies, acupoints used for insomnia with high frequency were GV20 (Baihui), PC 6 (Neiguan), SP 6 (Sanyinjiao), HT 7 (Shenmen), GV24 (Shenting), and Ex-HN1 (Sishencong),41,73 which are experience acupoints for insomnia. Previous studies selected acupoints based on experience but lacked the guidance of TCM theory. We believe that these studies did not fully represent TCM acupoints. The disadvantage of empirical acupoints is that logic suggests that the more acupuncture points are selected for the treatment, the better the effect will be; however, that is not what is observed. Therefore, many studies have used a total of 10 or more acupoints according to the empirical acupoint principle, which not only fails to achieve the expected effect,39 but also increases the subjects’ suffering. Therefore, this study abandoned the principle of empirical acupoints and selected acupoints based on TCM and meridian theory. According to the theory of TCM, the comorbidity of the heart and kidney is an important factor in the occurrence of insomnia. Heart belongs to fire, and kidney belongs to water. The relationship between the heart and kidney is one of interaction and restriction. The rise of Yang in the kidney can warm the heart fire, and the heart fire can drop to the kidney, which can nourish the Yin in the kidney. If the functional relationship between the heart and kidney is imbalanced, pathological changes will occur. In addition to insomnia, the symptoms of this imbalance include anxiety, depression and other unhealthy emotions. This study used the theory of harmony between the heart and kidney to treat insomnia. The selected acupoints HT 7 and KI 7 belong to the Hand Shaoyin Heart Meridian and Foot Shaoyin Kidney Meridian, respectively, which satisfy the attributes of meridians and Zang-Fu in the treatment of insomnia according to TCM. The selected points on the meridians with the same name have an appropriate relationship for the mother-son reinforcing-reducing method. The results showed that acupuncture at HT 7 and KI 7 for insomnia had a benign effect based on the theory of harmony between the heart and kidney.
In terms of objective sleep measures, this study found that acupuncture can improve SOL and sleep architecture. Compared with the sham acupuncture group, the acupuncture group showed a statistically significant decrease in SOL. With respect to sleep architecture, less time in stage N1 and more time in stage N3 were found in the acupuncture group. Other studies on acupuncture for insomnia have rarely explored sleep architecture, although some have used PSG as an objective measure. Some similar studies suggest that acupuncture can improve sleep architecture by increasing the percentage of slow wave sleep (SWS), thereby improving sleep quality,74 which was consistent with our study. However, regarding the effects of acupuncture on sleep maintenance and SE, the results of our study are inconsistent with those of similar studies. Studies have suggested that acupuncture can improve TST and SE.18,21 This study found that although the acupuncture group showed increases in TST and SE, there was no significant difference between the groups. This may be due to the use of data from only the second consecutive night of PSG monitoring for statistical analysis in this study to exclude the “first night effect”. Therefore, this result was more objective than previous studies, but due to the “first night effect”, subjects might have been prone to compensatory sleep on the second night; that is, they may have slept better than usual. That is why the baseline analysis of the study showed that the mean TST was >6 hours, and the room for improvement was small. There are different conclusions about the impact of acupuncture for insomnia on objective sleep measures, and it is limited by many factors. In the future, acupuncture researchers may pay more attention to the recovery and stability of the sleep architecture.
It is worth noting that acupuncture could improve comorbid symptoms, but the difference was not statistically significant compared with sham acupuncture. The reasons may be as follows: First, this study only selected two acupoints (HT 7 and KI 7) to treat insomnia and comorbid symptoms. When selecting the acupoints, we mainly considered that HT 7 and KI 7 can improve insomnia symptoms. Although HT 7 has the effect of improving depression and anxiety symptoms and KI 7 has the effect of improving fatigue symptoms, the effect of a single acupoint may not be sufficient. Second, this study only adopted ten acupuncture treatments. However, chronic insomnia is a long-term disease. Our course of treatment may be relatively short and fail to achieve the expected clinical effect. Finally, this study mainly recruited subjects diagnosed with chronic insomnia and excluded patients with mental illnesses such as anxiety and depression disorders. Although the subjects generally had symptoms of anxiety and depression, they did not meet the relevant diagnostic criteria. Because of the “floor effect”, the indicators improved, but the difference was not significant.
In addition, the results of this study showed that sham acupuncture had a benign effect on subjective and objective measurements. The results were similar to those of other clinical studies, suggesting that sham acupuncture has a certain clinical effect.39,40 A possible reason for this discrepancy may be that the participants we recruited had a positive attitude towards acupuncture treatment, and this high expectation might overoptimize the responses. The other reason may be that we used the true needle through, did not manipulate needles, and did not induce “De qi” but rather produced a shallow puncture through the skin.75 According to the theory of TCM, this sham acupuncture method belongs to the categories of “burr needling” and “shallow needling” in the Canon of Internal Medicine. It can exert curative effects by stimulating the twelve skin zones (superficial parts of human skin). In future research, we would expand the scope of recruitment and adopt more reasonable sham acupuncture methods.
Overall, acupuncture at HT 7 and KI 7 can significantly improve subjective and objective sleep indicators in subjects with chronic insomnia. While the subjects’ anxiety and depression were reduced, no significant difference compared with sham acupuncture was observed. Acupuncture at HT 7 and KI 7 failed to significantly improve the subjects’ daytime fatigue and sleepiness. Acupuncture at HT 7 and KI 7 for insomnia had short-term effects, and there was no significant difference between the groups during the follow-ups. This kind of acupuncture method has high safety and no obvious adverse effects and thus has value for further clinical exploration.
Limitations
This study has some limitations. First, the acupuncturist could not be blinded to the treatment group, and the measure of treatment fidelity was not established. Second, due to limited time and insufficient equipment, only some of the subjects were selected for PSG monitoring. The results may be not accurate. Finally, there was no difference between the two groups during the follow-up period. The precise effect duration of acupuncture at HT 7 and KI 7 needs more exploration.
Conclusions
The results of the current trial provide supportive evidence that acupuncture at HT 7 and KI 7 can be an effective, safe, and well-tolerated nonpharmacological intervention for insomnia using both subjective questionnaires and objective sleep measures. However, acupuncture at HT 7 and KI 7 can only provide a short-term effect, and a better combination of acupuncture points needs further exploration.
Acknowledgments
The authors thank Xiao-peng Ma from Shanghai Research Institute of Acupuncture and Meridian for her comments and suggestions on the study. We also thank Pin-xian Huang from Shanghai University of Traditional Chinese Medicine for her guidance on statistical methods. We also thank Wen-jia Yang, Xin-tong Yu and Na Zhao from Yueyang Hospital of Integrated Traditional Chinese and Western Medicine, Shanghai University of Traditional Chinese Medicine.
Funding Statement
Shanghai Clinical Research Centre for Acupuncture and Moxibustion (Grant No. 20MC1920500);The National Natural Science Foundation of China (Grant No. 81904300);The Shanghai Science and Technology Commission (Grant No. 18401971000);The Construction of Chinese Medicine Heritage Innovation Platform (Grant No. ZY (2018-2020)-CCCX-2004-03);The Shanghai Municipal Commission of Health and Family Planning (Grant No. ZYKC201703006).
Data Sharing Statement
The data that support the findings of this study are available from the corresponding author (Yun-fei Chen) upon reasonable request. Additionally, the individual deidentified participant data are available after contacting the corresponding author via email (moc.361@8691fyci). The data will be available immediately following publication without an end date.
Disclosure
The authors report no conflicts of interest in this work.
Article information
Nat Sci Sleep. 2021; 13: 1807–1822.
Published online 2021 Oct 10. doi: 10.2147/NSS.S326762
PMCID: PMC8519353
PMID: 34675728
Cong Wang,# 1 ,* Wen-lin Xu,# 1 ,* Guan-wu Li, 2 Cong Fu, 1 Jin-jin Li, 1 Jing Wang, 1 Xin-yu Chen, 3 Zhen Liu, 1 and Yun-fei Chen 1
1Department of Acupuncture and Moxibustion, Yueyang Hospital of Integrated Traditional Chinese and Western Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, People’s Republic of China
2Department of Radiology, Yueyang Hospital of Integrated Traditional Chinese and Western Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, People’s Republic of China
3Acupuncture and Tuina Academy, Beijing University of Chinese Medicine Dongfang College, Hebei, People’s Republic of China
#Contributed equally.
Correspondence: Yun-fei Chen; Zhen Liu Department of Acupuncture and Moxibustion, Yueyang Hospital of Integrated Traditional Chinese and Western Medicine, Shanghai University of Traditional Chinese Medicine, No. 110 Ganhe Road, Hongkou District, Shanghai, 200437, People’s Republic of China, Tel/Fax +86-21-65162628, Email icyf1968@163.com; liuzhen8918@163.com
*These authors contributed equally to this work
Received 2021 Jun 27; Accepted 2021 Sep 20.
Copyright © 2021 Wang et al.
This work is published and licensed by Dove Medical Press Limited. The full terms of this license are available at https://www.dovepress.com/terms.php and incorporate the Creative Commons Attribution – Non Commercial (unported, v3.0) License (http://creativecommons.org/licenses/by-nc/3.0/). By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed. For permission for commercial use of this work, please see paragraphs 4.2 and 5 of our Terms (https://www.dovepress.com/terms.php).
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