A Review of Key Research and Engagement in 2023–2024

Introduction

The Society for Acupuncture Research (SAR) was founded in 1993 at a time when the evidence for acupuncture’s efficacy was deemed to be insufficient, creating barriers to integration of acupuncture into mainstream health care. Formed by a group of scientists, the goal of SAR was to increase both the quality and quantity of research evidence on the efficacy, safety, and cost-effectiveness of acupuncture and related therapies, as well as to explore their underpinning biomechanisms. The past 31 years have seen an exponential increase in both quality and quantity of acupuncture research. In this annual review covering the academic year 2023–2024, notable studies and trends are highlighted. The process of identifying articles began by surveying SAR’s board and members, as well as practitioners and researchers at large, via social media recruitment. Following discussions on key trends and themes emerging from those articles, new studies in pain research, integrative oncology, and biomechanisms mediated via the gut–brain–microbiome and vagal–adrenal axis are highlighted here. Potential uses of artificial intelligence (AI) and digital health in the field of traditional East-Asian medicine (TEAM) are also discussed. Although the quantity of clinical trials has increased in the past year, the confidence levels have declined. Consequently, this review spotlights results from a systematic review and an audit of open science practices in journals that identified areas where improvement is needed.

Quality of Randomized Controlled Trials, Pragmatic Trials, and Open Science Practices

Since the comprehensive BMJ Acupuncture Series identified research priorities and produced guidance on randomized controlled trials (RCTs) in acupuncture in 2022, ¹ several articles this past year have added further contributions to issues in RCT quality, pragmatic trials, and the open science movement.

An evidence map of acupuncture ² reassessed systematic reviews on acupuncture for 43 conditions/diseases where evidence was previously unclear or potentially effective. ³ The number of RCTs for each condition has increased on average from 11 to 19.5, and nine more conditions were evaluated as effective/potentially effective, but confidence level of RCTs has worsened over time. Certainty of evidence in 2024 varied from very low to moderate, often related to risk of bias, poor study design, and poor reporting. Authors recommend development of a new critical appraisal tool and add their voice to the BMJ series’ call for a minimization of unnecessary research.

Using the PRagmatic Explanatory Continuum Indicator Summary-2 (PRECIS-2), a systematic review assessed the pragmatism of 93 self-declared pragmatic acupuncture studies and found that overall studies were pragmatic in the domains of eligibility, recruitment, organization, primary outcome, primary analysis, and control but were not pragmatic in the domains of setting, flexibility:delivery, and follow-up. ⁴ The lack of pragmatism in the flexibility:delivery domain, which assesses the degree to which treatments are individualized or based on practitioners’ discretion, is of particular note, as this is arguably the most important feature of pragmatic acupuncture trials. The main issue in this domain was strict acupuncture delivery protocols, and the authors recommend that future pragmatic trials need to both improve their pragmatic methods and report them in detail for each domain of the PRECIS-2 tool. ⁴

An audit of open science practices across complementary alternative and integrative medicine journals using the Transparency and Openness Promotion (TOP) guidelines ⁵ identified high variability in open science practices by 19 journals. ⁶ Four journals (21%) had a TOP factor of 0. The highest TOP factor was an 8 out of a maximum possible of 24. Journals most frequently had higher scores for requirements of data citation, design, and analysis transparency and had the lowest scores in the analysis plan, preregistration and replication categories. Journals frequently encouraged rather than required open science practices. The inclusion of open science practices may improve the usability and replicability of research, and authors hope that this audit will stimulate further work to understand and improve the usage of open science practices in these journals.

Pain

New evidence has emerged on acupuncture for acute pain and chronic pain. A multicenter RCT found that patients with chronic sciatica had significantly less pain and disability when treated with acupuncture compared with sham acupuncture. ⁷ Two hundred and twenty patients received treatment for 4 weeks, were followed up for 1 year, and showed consistent improvements. This trial was methodologically rigorous despite the limitations of using a sham control. ⁷

Another noteworthy trial was a two-stage adaptive pragmatic RCT, comparing two types of acupuncture with usual care for 236 emergency department (ED) patients with acute musculoskeletal pain. ⁸ Patients were randomized to receive either auricular acupuncture (AA), peripheral acupuncture (PA), or usual care (UC). All patients from both acupuncture groups also received usual care. Compared with UC alone, both AA and PA had reductions in pain scores at 1-h post-treatment, but only AA showed clinically significant improvement. ⁸ The trial’s study design included two essential features—pragmatism and adaptation; this allows real-time adjustments based on the ongoing data findings, which are important in real-world settings like the ED.

The advances in acupuncture for pain relief were narratively reviewed to update the existing evidence base for research and clinical practice. ⁹ Acupuncture, either on its own or alongside other therapies, is widely used for pain management, with growing evidence supporting the effectiveness from both basic and clinical research. Despite the variable quality of supporting evidence, the review concluded that the potential of acupuncture for cost-effectiveness and its low-risk profile, when performed using standardized techniques, make it a viable option to consider as a nonpharmacologic treatment for pain. ⁹

Integrative Oncology

In line with the publication of the guideline for integrative medicine for pain management in oncology, ¹⁰ the evidence for integrative interventions during cancer care continues to grow, ¹¹ with new findings supporting benefits of acupuncture, Tai Chi or qigong, yoga, and other mindfulness-based interventions to address cancer fatigue, depression, and anxiety. ^10,12

Along with acupuncture for aromatase inhibitor-associated arthralgia, general and perioperative or procedural pain, ¹³ and electroacupuncture (EA) for breast cancer survivors with chronic musculoskeletal pain, ¹⁴ research also highlighted how acupressure and massage can be used for relief of pain during systemic therapy and pain during palliative and hospice care, respectively. ¹³

Acupuncture may also help patients affected by lymphoma by improving pain and neuropathy and relieving nausea/vomiting, fatigue, and insomnia. ¹⁵ In a study conducted at a comprehensive cancer center in the United States, after a single acupuncture treatment, patients reported clinically significant improvements in pain and neuropathy; decrease in lack of well-being, tiredness, nausea, anxiety, activities of daily living issues, depression, anorexia, insomnia, and shortness of breath (outpatients, n = 309); and reduction in anxiety, nausea, insomnia, depression, pain, neuropathy, anorexia, constipation, and diarrhea (inpatients, n = 394). ¹⁶

In an Australian feasibility study on breast cancer survivors (n = 20) receiving an individualized, pragmatic 6-week acupuncture intervention, participants agreed that acupuncture was feasible (85%), acceptable (90%), and appropriate (90%). ¹⁷ Results also showed that both mean and composite symptom cluster scores were significantly reduced and so were individual symptom scores in fatigue, sleep disturbance, and numbness/tingling. ¹⁷

Remarkably, the first international, multidisciplinary peer-reviewed recommendations for safe practice of acupuncture in integrative oncology were recently published, primarily aiming at supporting safe care and addressing previously identified barriers to uptake by patients and appropriate referral from oncology teams. ¹⁸

While oncology researchers and clinicians show great interest in the use of complementary and integrative medicine in oncology, ¹⁹ oncologists have reported cost as the primary barrier to acupuncture care in the oncology setting, with additional barriers to implementation, including concerns about competency and training, as well as accessibility and safety of herbal medicine during treatment. ²⁰ Lack of knowledge of benefits and contraindications, along with gaps in education, has also been identified by health care providers as a barrier for integration of complementary and integrative medicine in cancer care. ²¹

Biomechanisms of Acupuncture in Improving Cognitive Impairment

Two new reviews examined different aspects of the effects of acupuncture, EA, and moxibustion in improving cognitive impairment, one focusing on the microbiome–gut–brain axis and the other on the role of the c-Jun N-terminal kinase (JNK) signaling pathway. ^22,23

A review by Shi et al. 2024 highlighted the importance of the microbiome–gut–brain axis in the development of cognitive impairment. ²² Acupuncture and moxibustion have been shown in animal experiments to improve cognitive impairment via various pathways. First, acupuncture and moxibustion can improve cognitive function by modifying the species and diversity of intestinal flora. Second, acupuncture and moxibustion have been shown to regulate the neuroendocrine–immune system by modifying the balance between Th17 cells and Treg cells (and the pro-inflammatory and anti-inflammatory cytokines which they produce). Third, acupuncture’s anti-inflammatory effects on the intestinal mucosa have also been shown to be mediated by downregulation of pro-inflammatory neuropeptides such as Substance P and vasoactive intestinal peptide, the upregulation of neurotrophins such as brain-derived neurotrophic factor, as well as increasing vagal–adrenal stimulated production of dopamine. Finally, acupuncture and moxibustion improved the integrity of the intestinal barrier. ²²

A review by Liu et al. 2023 explored the role of the JNK signaling pathway in cognitive impairment. ²³ EA significantly inhibited hippocampal neuronal apoptosis and improved cognitive impairment in vascular dementia model mice. EA was found to inhibit phosphorylation of JNK and caspase-3. ²³

The Vagal–Adrenal Axis: Efferent of Afferent?

The term “vagal–adrenal axis” has been used in a number of studies to describe an anti-inflammatory pathway stimulated by acupuncture in which efferent nerve fibers from the vagus nerve innervating the adrenal glands drive catecholamine release. ^{24 –26} However, a new study disputes this characterization and proposes that it is in fact vagal afferent fibers, not vagal efferent fibers, which are responsible for this acupuncture anti-inflammatory effect. ²⁷ Trevisan-Bau and McAllen argue that evidence for any direct vagal efferent innervation of the adrenal glands is weak, although vagal afferent fibers do directly innervate the adrenal gland. Furthermore, a number of indirect pathways have been demonstrated whereby vagal afferent fibers modify adrenal anti-inflammatory responses via the central nervous system. ²⁷

AI and Digital Health

In the emerging field of AI, articles exploring the potential role that AI might play in acupuncture and TEAM, along with description of AI projects already happening, continue to emerge. Potential areas for use of AI may include the following: individual diagnostic enhancement and personalized medicine, for example, through analysis of individual patient data and generation of recommendations; detection of patterns in acupoint/treatment options for specific conditions from analysis of large data sets; health coach “bots” that could provide patient support; and detection and diagnosis of physiologic signs and signals, such as facial, tongue, and pulse analysis or heart rate and skin conductivity during acupuncture treatment. ^{28 –30} Data mining and large-scale retrospective analysis of big data have been used to address clinical questions about acupuncture, which trials have not yet answered. ³¹ A study in the development of computer vision systems using 5260 tongue images accurately diagnosed 58 images out of 60 in real-time testing. ³² The potential of such tongue diagnostic tool includes integration into telemedicine platforms and use in remote monitoring of health issues. ³² In the realm of machine learning, researchers in China used pulse wave parameters and clinical indices collected by two TEAM practitioners to establish and verify a prediction model algorithm for distinguishing between patients with polycystic ovary syndrome (PCOS) and patients without PCOS with irregular menstruation. ³³ This new machine learning prediction model might not only offer a possible noninvasive and cost-effective way to diagnose PCOS but also it may provide objective evidence for TEAM diagnosis. ³³

Moving Forward

Building on a successful 2024 joint SAR and Poly/U conference in Hong Kong, ³⁴ SAR continues to provide a global platform for researchers and practitioners alike to explore opportunities and address challenges in all aspects of acupuncture and TEAM research, including the novel area of AI and digital health. ^30,31 Discussions on these and many other topics are planned for the upcoming 2025 SAR International Research Conference in Newport Beach, CA, USA.