Letter to the Editor: High-frequency abdominal vibration in prediabetes - psychophysiological insights into mental health and glycemic control

Abstract

Prediabetes is simultaneously a metabolic and psychological challenge because depression, anxiety, and stress worsen insulin resistance. Globally, prediabetes affects about 10% of adults and exceeds 30% in middle-aged and older populations, representing a significant public health concern. Current lifestyle and pharmacological interventions often show limited long-term adherence and efficacy, emphasizing the need for complementary mind-body approaches. The study by Liu et al, published in the recent issue of the World Journal of Psychiatry, applied a standardized abdominal Tuina vibration protocol using frequencies of 400-600 cycles per minute (approximately 6.7-10 Hz), with the highest frequency producing the most notable improvements in depression, anxiety, stress, and insulin resistance. Their findings support a dose-response relationship that may involve mechanisms related to improved microvascular perfusion, vagal activation, reduced hypothalamic-pituitary-adrenal axis activity, and the modulation of inflammatory and adipokine signaling, although these pathways were not directly assessed in the study. These effects converge on mood stabilization and glucose regulation. High-frequency abdominal Tuina vibration is noninvasive, inexpensive, and may provide dual psychological and metabolic benefits in adults with prediabetes.

Key Words: Prediabetes; Tuina abdominal vibration; Psychological symptoms; Insulin resistance; Integrative medicine

Core Tip: The study by Liu et al demonstrated high-frequency abdominal Tuina vibration at the Shenque acupoint significantly improves psychological symptoms (depression, anxiety, stress) as well as insulin resistance in adults with prediabetes. A clear dose-response relationship was observed, indicating that higher frequencies produce stronger psychophysiological effects (600 counts per minute, approximately 10 Hz). This noninvasive, low-cost intervention may integrate mind-body mechanisms to enhance both metabolic control and emotional well-being, although these mechanisms were not directly measured in the study. The simplicity, safety, and cultural adaptability of this approach support its promise as an adjunct to lifestyle and pharmacological prediabetes management.

TO THE EDITOR

Recent estimates indicate that approximately one in ten adults worldwide lives with prediabetes, with prevalence surpassing 30% in middle-aged and older groups[1,2]. This condition imposes substantial healthcare and economic burdens due to its progression risk and its close association with cardiovascular and psychological comorbidities[1-3]. Current preventive strategies (mainly lifestyle modification and pharmacological interventions) often face limited long-term adherence and effectiveness. Therefore, complementary strategies that integrate biological and psychological dimensions are increasingly relevant. The psychological burden of prediabetes, including depression, anxiety, and stress, has been shown to aggravate insulin resistance and complicate clinical management[4,5]. Accordingly, a therapeutic approach that addresses both metabolic and psychological components is timely and clinically relevant.

Tuina is a standardized manual therapy within traditional Chinese medicine that employs graded techniques (pressing, rubbing, stretching, and vibration) applied to meridians or acupoints[3,6]. Abdominal vibration at the Shenque acupoint (navel region) may contribute to biologically plausible effects on autonomic regulation, visceral function, and metabolic balance through a frequency-controlled mechanical stimulus. Although these effects were not directly measured in the recent prospective study of adults with prediabetes conducted by Liu et al[3], published in the recent issue of the World Journal of Psychiatry, the investigators demonstrated that high-frequency abdominal Tuina vibration significantly improved depression, anxiety, stress, and insulin resistance. Notably, their use of a defined high-frequency stimulus (approximately 10 Hz) produced clinically meaningful effects, supporting the view that frequency may function as a biological dose. This observation supports a dose-response framework for manual vibration therapies[3] and raises mechanistic hypotheses about thresholds that may trigger systemic adaptations without adverse effects; furthermore, this finding is consistent with psychophysiological interactions reported in metabolic regulation studies, despite the underlying biological pathways having not been directly assessed[3,4,6].

Tuina vibration offers a distinctive mechanistic profile due to its quantifiable mechanical dose and its potential influence on visceral and autonomic pathways[6]. Unlike relaxation-based or purely cognitive approaches, the defined-frequency vibration stimulus provides measurable somatosensory input that may be capable of modulating psychological and metabolic responses[3]. Therefore, abdominal Tuina vibration may represent a complementary or synergistic option within the broader spectrum of integrative mind-body therapies[3,6]. From a mechanistic standpoint, abdominal vibration may engage several convergent and biologically plausible pathways, including the following: (1) Local hemodynamics, in which rhythmic mechanical input may increase microvascular perfusion and tissue oxygenation, may promote shear-stress mediated nitric oxide release, and may recruit capillary networks, and whereby enhanced perfusion could favor oxygen delivery, facilitate the removal of lactate and other metabolites, and attenuate nociceptive signaling, thereby potentially facilitating short-term autonomic rebalancing[4-6]; (2) Autonomic modulation, in which stimulation of the autonomic nervous system may enhance vagal activity and temper sympathetic output, potentially attenuating hypothalamic-pituitary-adrenal axis activation and cortisol release (factors tightly coupled to mood and glycemic variability)[3-5]; (3) Downstream immunometabolism signaling, which may involve shifts in inflammatory cytokine profiles, such as those of interleukin (IL)-6, tumor necrosis factor-alpha, IL-1β, and IL-10, while adipokine signaling (leptin, adiponectin, resistin, and visfatin) may be indirectly modulated via the cholinergic anti-inflammatory reflex and improved tissue perfusion[4-6]; and (4) Neuroendocrine-metabolic interactions, which may intersect with recognized links among stress, mood, and metabolism (to reiterate for importance: This is despite the lack of direct measurements of these pathways in the study by Liu et al[3]). Low-grade inflammation and gut-brain crosstalk have been implicated in insulin resistance and affective symptoms, potentially contributing to dual emotional and metabolic benefits[2,5,6]. Clinically, these pathways may help explain improvements not only in overall mood but also across specific subtypes of depression and anxiety characterized by fatigue, tension, and somatic distress. The gentle rhythmic stimulation may enhance interoceptive awareness, self-compassion, and relaxation responses, which are psychological mechanisms thought to reinforce emotional regulation and resilience. Through these mind-body connections, abdominal vibration could facilitate behavioral adherence to dietary and exercise recommendations, thereby potentially supporting sustained metabolic benefits[3-5].

The study by Liu et al[3] had several methodological strengths, including a prospective design, validated outcome measures, and a 12-month follow-up, which collectively bolster confidence in the clinical signal. Its integrative framing positioned psychological well-being as a potential driver, rather than a by-product of metabolic control. Clinically, the technique is noninvasive, inexpensive, and compatible with lifestyle counseling, and it is performed during brief, structured sessions that may help improve adherence. The defined vibration frequency also provides a practical lever for standardization across settings[3,6]. Nevertheless, safety and ethical considerations deserve explicit discussion. Abdominal vibration should be applied cautiously and under medical supervision. Contraindications include acute abdominal inflammation, pregnancy, abdominal hernia, recent abdominal surgery, and active infection. Ethical practice requires informed consent, proper screening, and practitioner training to ensure patient safety. Individualized dosing and careful monitoring of abdominal conditions are recommended, especially in patients with cardiometabolic comorbidities[3,4,6]. Clear reporting of device specifications, standardized training in Tuina safety protocols, and clearly defined parameters of session frequency and duration will be essential to ensure reproducibility and maintain patient safety during clinical implementation. Anatomical considerations and preparedness for emergency response are likewise necessary to safeguard the ethical and clinical integrity of the procedure. Clear inclusion and exclusion criteria, combined with ongoing supervision, may help reduce mechanical or hemodynamic complications. Establishing formal certification standards could further enhance reproducibility and patient safety in both future research and clinical practice.

LIMITATIONS

While the findings of Liu et al[3] are promising, the study’s modest sample size (n = 120) and single-center design may restrict external generalizability. Furthermore, the lack of blinding and absence of biomarker-based endpoints limited the investigations into mechanistic inference. Future works should incorporate objective biomarkers and mechanistic readouts, such as heart-rate variability (as an index of autonomic balance), diurnal cortisol profiles, panels of proinflammatory and anti-inflammatory cytokines, and selected adipokines, to strengthen their translational relevance. Vascular endpoints, including reactive hyperemia testing or laser-Doppler assessment of skin and splanchnic perfusion, could help in efforts to quantify local circulatory effects. Exploratory microbiome profiling may help delineate the gut-brain-metabolic interfaces. Multicenter randomized trials across diverse populations with longer follow-ups are warranted to establish generalizability, durability, and dose parameters, particularly regarding optimal frequency ranges (approximately 10 Hz)[3,6]. In addition, comparative studies contrasting Tuina vibration with other mind-body therapies such as yoga, meditation, acupuncture, or vagal stimulation would help in determining its relative efficacy as well as its complementary potential. Further refinement of vibration parameters and treatment protocols may improve cross-study comparability and guide optimal implementation. Future research should integrate mixed-methods designs that combine physiological biomarkers with qualitative assessments of patient experience, cultural acceptability, and adherence to capture the multidimensional impact of the intervention. Finally, developing a unified conceptual framework for frequency-based manual therapies could further support the translation of these findings into clinical guidelines.

CONCLUSION

In summary, high-frequency abdominal Tuina vibration aligns with a modern and mechanistically informed vision of integrative care for patients with prediabetes. By improving psychological symptoms and insulin resistance simultaneously, this mind-body intervention may help leverage neuroendocrine and metabolic pathways to enhance both metabolic health and patient well-being. Its simplicity, safety, and accessibility may make it a feasible adjunct to lifestyle and pharmacological interventions for early metabolic risk. Continued refinement of vibration protocols and broader cultural and clinical validation will be important for advancing its translational potential. Ultimately, however, this approach illustrates how integrative, low-cost strategies may bridge physiological and psychological domains of care, promoting holistic health in individuals with prediabetes.