Efficacy of Acupuncture in Managing Radiation-Induced Xerostomia: An Updated Meta-Analysis

Abstract

Background: Xerostomia, or dry mouth, frequently affects head and neck cancer patients receiving radiotherapy, leading to discomfort and impacting daily functions such as speaking and swallowing. Conventional treatments may offer limited relief and are often accompanied by undesirable side effects. Acupuncture, as a non-pharmacological intervention, is increasingly explored for its potential to mitigate xerostomia symptoms. Objective: This systematic review and meta-analysis aim to assess the effectiveness of acupuncture in improving symptoms and quality of life in patients experiencing radiation-induced xerostomia. Methods: A thorough literature search was conducted across several databases, including MEDLINE, Embase, Cochrane Central, and Web of Science, up to the current year. We included randomized controlled trials (RCTs) that evaluated acupuncture's impact on salivary flow and symptom relief in adults with radiation-induced xerostomia. Primary outcomes were changes in salivary flow, with secondary outcomes including patient-reported symptom severity and quality of life metrics. The risk of bias was evaluated, and data were synthesized using a random-effects model. Results: A total of 11 RCTs involving 1271 participants were included in the analysis. The pooled data showed a moderate increase in salivary flow in the acupuncture group, effective in both resting and stimulated conditions. Additionally, acupuncture demonstrated significant benefits in reducing xerostomia symptoms and improving quality of life scores compared to control interventions. Subgroup analysis revealed that traditional acupuncture was more effective than Transcutaneous Electrical Nerve Stimulation (TENS). Conclusions: The findings suggest that acupuncture may be an effective complementary treatment for radiation-induced xerostomia, offering relief from dry mouth symptoms and potentially improving quality of life. Further research should focus on standardizing acupuncture protocols to confirm these benefits across diverse patient populations.

Keywords: cancer; dry mouth; quality of life.; salivary flow; systematic reviews.

Figure 1

Flowchart depicting the study selection process for this systematic review and meta-analysis on acupuncture interventions for radiation-induced xerostomia. Of the 277 records initially identified, 11 studies fulfilled the inclusion criteria and were included in the final analysis.

Figure 2

Assessment of methodological quality of the included trials. (A) Risk of bias for each included study. (B) The overall summary of bias of the ten studies.

Figure 3

Visualization of the effects of acupuncture on resting salivary flow. Panel (A) highlights the overall impact on resting salivary flow, while panel (B) presents subgroup analyses by treatment type. In the forest plots, squares indicate standardized mean differences favoring acupuncture (shifted to the left), with horizontal lines representing the 95% confidence intervals. The diamond symbol at the bottom reflects the pooled effect size.

Figure 4

Illustration of the effects of acupuncture on stimulated salivary flow. Panel (A) shows the overall impact on stimulated salivary flow, while panel (B) provides subgroup analyses by treatment type. In the forest plots, squares represent standardized mean differences favoring acupuncture (shifted to the left), with horizontal lines indicating the 95% confidence intervals. The diamond symbol at the bottom summarizes the pooled effect size.

Figure 5

Depict of the effects of acupuncture on xerostomia questionnaire scores. Panel (A) presents the overall impact on xerostomia questionnaire scores, while panel (B) includes subgroup analyses by treatment type. In the forest plots, squares represent standardized mean differences favoring acupuncture (shifted to the left), with horizontal lines showing the 95% confidence intervals. The diamond symbol at the bottom reflects the pooled effect size.

Figure 6

Depiction of the effects of acupuncture on quality of life. Panel (A) presents the overall impact on quality of life, while panel (B) includes subgroup analyses by treatment type. In the forest plots, squares indicate standardized mean differences favoring acupuncture (shifted to the left), with horizontal lines representing the 95% confidence intervals. The diamond symbol at the bottom reflects the combined effect size.

Figure 7

Shows a funnel plot summarizing the results from the studies included in Figure 3A. The lines illustrate the confidence intervals around the effect estimates, indicating the range where the true effect size is likely to fall. Circles represent individual studies included in the meta-analysis, with their size potentially reflecting the weight or sample size of each study; larger circles correspond to studies with greater weight or larger sample sizes. The diamond symbol denotes the overall effect estimate from the meta-analysis, with the center marking the pooled effect size and the width indicating the confidence interval for this estimate.