Prediabetes refers to a state of impaired glucose metabolism, including impaired fasting glucose and glucose tolerance [1,2]. The development of prediabetes is associated with insulin resistance and dysfunction of insulin-secreting pancreatic β-cells [3]. This condition carries a significant risk of progression to type 2 diabetes, as β-cell dysfunction can further exacerbate insulin resistance and vice-versa, creating a positive feedback loop [4]. The global prevalence of prediabetes has increased rapidly in recent years [4]. According to predictions by the International Diabetes Federation, the number of adults with impaired fasting glucose and impaired glucose tolerance worldwide is expected to increase to 369.7 million and 622.7 million, respectively, by 2030 [5]. The American Diabetes Association indicates that up to 70 % of individuals with prediabetes may develop type 2 diabetes in the absence of appropriate interventions [6]. Furthermore, prediabetes is associated with an increased risk of cardiovascular diseases, tumors, and dementia [7,8]. Prediabetes is currently considered a reversible condition, with proactive and appropriate interventions significantly reducing the risk of developing type 2 diabetes and its various associated complications. Prediabetes treatment mainly includes lifestyle interventions such as dietary control and moderate exercise, as well as the use of hypoglycemic drugs such as metformin [9]. However, long-term lifestyle interventions are challenging for some patients, and concerns have been raised in relation to the long-term effects of antidiabetic medications [10]. While antidiabetic medications can regulate the blood glucose levels of patients with prediabetes within normal ranges during treatment, insulin resistance and progression to diabetes tend to remain unaffected once these medications are discontinued [11,12]. In addition, although plant-based therapies, such as okra (Abelmoschus esculentus (L.) Moench), have been found to reduce fasting blood glucose (FBG) levels in individuals with prediabetes and type 2 diabetes, they do not significantly affect glycosylated hemoglobin A1c (HbA1c) levels [13]. Therefore, a sustainable treatment strategy is needed to reduce blood glucose levels in patients with prediabetes.

In recent years, acupuncture and its derived acupoint stimulation techniques, such as auricular acupressure and acupoint catgut embedding, have received increasing attention as auxiliary interventions [14]. One meta-analysis reported that acupuncture significantly reduced HbA1c, FBG, 2-h postprandial blood glucose (2h-PBG), fasting insulin (FINS), and homeostasis model assessment of insulin resistance (HOMA-IR) levels in patients with type 2 diabetes [15]. Another meta-analysis reported that acupuncture-related therapies improved glucose metabolic status in patients with prediabetes and reduced diabetes incidence [16]. A subsequent animal study reported that targeted acupoint stimulation significantly improved pancreatic β-cell function and peripheral insulin sensitivity in a rodent model of diabetes, providing a mechanistic rationale for its transformative potential in treating type 2 diabetes [17]. As an acupuncture-related treatment, auricular acupressure has gradually gained popularity among researchers owing to its noninvasive nature. Auricular acupressure refers to a therapy in which hard and smooth pellets, such as Vaccaria seeds and magnetic beads, are attached to the surfaces of acupoints on the ears, and these acupoints are stimulated by pressing, compressing, kneading, and pinching [18]. Traditional Chinese medicine theory states that auricular acupressure regulates the functions of diseased tissues and organs through mild and sustained acupoint stimulation [19]. Owing to its high safety, simple operation, and affordability, auricular acupressure has been used in China to treat various diseases, including obesity, insomnia, and anxiety [[20], [21], [22]]. Auricular acupressure for diabetes was first reported in the 1990s. In 1994, Cheng et al. [23] first reported its role in promoting insulin release and lowering blood glucose. In 2006, Zhen et al. [24] showed that, for the first time in a clinical trial, auricular acupressure significantly reduced FBG and postprandial blood glucose levels in individuals with impaired glucose tolerance. Its role in the prevention of prediabetes and the transition to diabetes has since gained increasing attention. However, owing to a lack of high-quality evidence, the specific benefits of auricular acupressure for treating prediabetes remain unclear. Moreover, the optimal acupoints for auricular acupressure are yet to be elucidated.

In this study, we conducted a meta-analysis and trial sequential analysis (TSA) to evaluate the efficacy and safety of auricular acupressure for treating prediabetes. We applied data mining to determine the optimal acupoints for this intervention, aiming to increase complementary and alternative treatment options available for prediabetes.