Among neurodegenerative (GBD 2016 Parkinson's Disease Collaborators, 2018) diseases, Parkinson’s disease (PD) is the second most prevalent, and forecasts indicate that its incidence will likely treble within the next three decades (Tansey et al., 2022; Tolosa et al., 2021). Neuropsychiatric manifestations are commonly observed in individuals with PD throughout the course of the disease (Weintraub et al., 2022). It is common for non-motor signs of PD, such as hyposmia, sleep problems (Gros and Videnovic, 2020; Iranzo et al., 2024), depression, and constipation (Schapira et al., 2017), to appear by many years before the motor symptoms of the disease. Among these non-motor symptoms (Chaudhuri et al., 2006), anxiety is particularly prominent and typically lacks effective treatment options. Anxiety in PD not only exacerbates the burden on caregivers but also worsens motor symptoms, increases the fear of falling, and may contribute to cognitive deterioration (Aarsland et al., 2021; Jellinger, 2022) decline (Dissanayaka et al., 2010). For those affected by PD, anxiety has been shown to have a more profound negative impact on quality of life compared to depression. Individuals with PD commonly experience anxiety, with a prevalence of 31% (Ascherio and Schwarzschild, 2016; Ben-Shlomo et al., 2024; Carey et al., 2021; Tysnes and Storstein, 2017), approximately twice that of the general population (15%) (Broen et al., 2016). Moreover, gait disturbances and freezing of gait have been associated with anxiety symptoms. Consequently, anxiety should be recognized as a significant symptom in PD, particularly in the context of dyskinesia (Mirelman et al., 2019).

The prevalence of anxiety in patients with Parkinson’s disease (20–46%) is higher than that of depression (17% for major depression, 22% for mild depression), and anxiety exerts a more pronounced negative impact on quality of life by directly impairing motivation, treatment adherence, and cognitive function (Reijnders et al., 2008; Opara et al., 2012; Ehgoetz Martens et al., 2016). However, there are only a few treatment modalities for anxiety in PD (Martens et al., 2016; Tolosa et al., 2006). Cognitive behavioral therapy (CBT) has been identified as an effective nonpharmacological intervention for depression and anxiety in PD (Cook et al., 2017; Kwok et al., 2019; Mak et al., 2017; Vijiaratnam et al., 2021). Despite its efficacy, the high cost of CBT has led to reduced patient adherence (Pachana et al., 2013). Emerging evidence suggests that acupuncture may be comparable in efficacy to CBT (Chae et al., 2008). Considering acupuncture’s treatment duration, time commitment, and cost, it may be more widely accepted for PD’s treatment in China. Given the situation of current treatments for anxiety in PD, there is an increasing demand in Western societies to investigate effective alternative therapies that offer high feasibility and fewer adverse effects. According to clinical guidelines, acupuncture and moxibustion are recommended as a Grade B treatment intervention for addressing the mental symptoms of PD, potentially supplementing or replacing existing therapeutic approaches (Cho et al., 2018; Noh et al., 2017; Weintraub et al., 2022). Randomized controlled trials (RCTs) of acupuncture in PD have been published successively (Li et al., 2023). Acupuncture is believed to ameliorate motor symptoms and associated anxiety by stimulating specific acupuncture points, which in turn may modulate the balance of neurotransmitters within the central nervous system, such as by increasing dopamine release. Additionally, acupuncture may facilitate the release of inhibitory neurotransmitters like gamma-aminobutyric acid (GABA), potentially reducing anxiety levels (Chen et al., 2020). However, the quality of these studies varies, which can be a disadvantage for clinicians seeking high-quality evidence and potential treatment strategies.

This article intends to establish a framework for clinical decision-making and compile pertinent randomized controlled studies to assess the feasibility and safety of acupuncture as a treatment for anxiety in PD. The assessment is guided by the principles of evidence-based medicine (Heneghan et al., 2017).

This comprehensive review and meta-analysis of randomized controlled trials (RCTs) demonstrates that acupuncture is both safe and effective for treating anxiety in people who have PD. This study assesses the effectiveness and safety of acupuncture and moxibustion in reducing anxiety symptoms related to PD. The evaluation is based on 10 RCTs. According to the data, acupuncture is a good way to manage anxiety in this demographic, and there have not been any serious adverse effects reported.

Our meta-analysis indicates that multiple acupuncture interventions, such as acupuncture alone, the combination of western medicine and acupuncture, empathic care with acupressure, and auricular pressure point stimulation, administered over durations of 9 to 84 days, resulted in significant improvements in HAMA/SAS scores among patients experiencing anxiety related to PD, relative to control groups. Despite these findings, the evidence regarding the effectiveness of acupuncture in alleviating specific anxiety symptoms, including excessive worry, fear, and fatigue, is inadequate. The significant heterogeneity observed across the studies in this review underscores the necessity for additional research employing more rigorous methodologies to confirm these preliminary findings.

This substantial heterogeneity might stem from the variability in acupuncture techniques across studies, including variances in treatment dose and frequency, acupoint selection, the skill level of session length. Additionally, it could be attributed to the wide age range and diverse levels of anxiety among participants. Previous meta-analyses have frequently highlighted the pervasive heterogeneity in acupuncture treatments. Even people with the same ailment may have various homeostatic imbalances, according to traditional Chinese medicine’s theoretical framework. This has turned into one of the most challenging issues in the systematic review and distribution of acupuncture research (White et al., 2008). It is worth noting that standardization of acupuncture practices is still a topic of debate.

The subgroup analyses in this study revealed several interesting findings. Treatment duration and acupuncture type may be key factors influencing therapeutic efficacy; however, these results should be interpreted with caution. First, subgroup analyses are observational in nature and may be affected by confounding factors. As all included patients were elderly, they may have had more comorbidities, and the observed differences may not be entirely attributable to treatment duration or specific acupuncture techniques. Second, the limited number of studies in certain subgroups may have resulted in insufficient statistical power, increasing the risk of false-positive or false-negative outcomes. Therefore, these subgroup findings should be regarded as exploratory and hypothesis-generating rather than conclusive.

The Cochrane Risk of Bias Assessment Tool (Higgins et al., 2011) notes that failure to implement blinding of investigators/participants may lead to an overestimation of effect sizes (on average approximately 15–20%). The unique nature of acupuncture procedures (e.g., the sensation of deqi) makes complete blinding difficult to achieve, but the absence of assessor blinding amplifies measurement bias in subjective scales (e.g., HAMD/SDS). Only two of the 10 studies (Fan et al., 2022; Zhu et al., 2025) were pre-registered in the China Clinical Trial Registry, while the remaining studies carry a risk of protocol deviation, which undoubtedly increases the risk of selective reporting (e.g., hiding negative results or adjusting the analysis protocol).

This study’s GRADE evidence quality assessment demonstrated considerable variation in the strength of evidence among the different outcome measures. The HAMA was rated as high quality, providing strong confidence that the estimated effect of acupuncture on reducing anxiety is reliable. In contrast, both the SAS and HAMD were graded as moderate, indicating that while the current results are likely valid, further studies could still impact these conclusions. Heterogeneity in these outcomes may stem from differences in study design or intervention details. Some studies used routine care as the control group (non-active control), which may have overestimated the efficacy of acupuncture. It is recommended to emphasize preliminary evidence rather than definitive conclusions. The SDS was assessed as low quality, implying limited confidence in the effect estimates, likely due to risk of bias, imprecision, or inconsistency among studies. Thus, findings related to SDS should be considered exploratory and require validation through more rigorous trials.

Acupuncture can reduce the activation of the cortex and limbic system (Lin et al., 2023; Xu et al., 2023) in PD patients, areas associated with emotion regulation and anxiety. By decreasing the hyperactivation of these regions, acupuncture may alleviate anxiety symptoms (Deuel and Seeberger, 2020). Acupuncture has the potential to reduce anxiety symptoms through its effects on the hypothalamic–pituitary–adrenal (HPA) axis (Zheng et al., 2024), leading to decreased secretion of stress hormones like cortisol. Acupuncture may reduce anxiety symptoms by modulating serotonin (5-HT) and norepinephrine (NE) levels (Lu et al., 2022), as these neurotransmitters are essential for mood regulation (Höglinger et al., 2024; Tan et al., 2020).

The limitations of this review primarily stem from the inherent shortcomings of the included studies. As the meta-analysis was based on a limited number of studies, the generalizability of the conclusions is constrained, statistical power is reduced, and the strength of evidence (affecting the GRADE assessment) is diminished. The use of subjective scales as outcome measures may introduce reporting biases due to their susceptibility to subjective interpretation. Furthermore, individual researchers may have brought their own perspectives when interpreting the findings of the reviewed studies, potentially introducing bias. This study lacks long-term follow-up to evaluate the sustainability of the therapeutic effects. Therefore, the findings of this study should only be considered preliminary evidence.

Acupuncture therapy has significant promise as an alternate treatment for relieving PD anxiety in patients. However, additional large-sample, high-quality RCTs are needed to confirm its efficacy and determine which types (e.g., electroacupuncture, moxibustion, and auricular acupuncture) and dosages (e.g., frequency and duration of therapy) are most helpful to patients. Additionally, future RCTs should incorporate a follow-up period of at least 3 months to evaluate the sustainability of therapeutic effects. The optimal acupuncture regimen remains to be determined based on current evidence. They highlight directions for future research, such as designing more refined clinical trials to validate the efficacy of different types of acupuncture. Future studies should adopt sham-needle blinding and third-party blinding to minimize measurement bias and implementation bias.

Preliminary evidence suggests that acupuncture may be effective in alleviating anxiety symptoms in patients with PD. Furthermore, in clinical practice, acupuncture is regarded as a safe technique that may be useful as an alternative or adjunctive treatment. Additional higher quality randomized controlled trials are required to ascertain the safety and effectiveness of acupuncture as a therapy for anxiety in PD patients.