Efficacy and safety of acupuncture and moxibustion for primary tinnitus: A systematic review and meta-analysis

Tinnitus is a common otological symptom that can seriously affect a patient's quality of life, and effective therapies are still lacking. A large number of studies have found that compared with traditional therapy, acupuncture and moxibustion treatment are beneficial for the treatment of primary tinnitus, although current evidence remains inconclusive. This systematic review and meta-analysis of randomized controlled trials (RCTs) aimed to evaluate the efficacy and safety of acupuncture and moxibustion for primary tinnitus. We conducted a comprehensive literature review in multiple databases from inception through December 2021, including PubMed, Medline, Ovid, Embase, Science Direct, Chinese National Knowledge Infrastructure (CNKI), Wanfang Data, Chinese Biomedical Literature (CBM) and VIP Database. The database search was supplemented by subsequent periodic scrutiny of unpublished and ongoing RCTs from the Cochrane Central Register of Controlled Trials (CENTRAL) and the WHO International Clinical Trials Registry (ICTRP). We included RCTs that compared acupuncture and moxibustion with pharmacological therapies, oxygen or physical therapies, or no treatment, for treating primary tinnitus. The main outcome measures were Tinnitus Handicap Inventory (THI) and efficacy rate; the secondary outcome measures were Tinnitus Evaluation Questionnaire (TEQ), Pure Tone Average (PTA), Visual Analogue Scale (VAS), Hamilton Anxiety Scale (HAMA), Hamilton Depression Scale (HAMD) and adverse events. Data accumulation and synthesis included meta-analysis, subgroup analysis, publication bias, risk-of-bias assessment, sensitivity analysis, and adverse events. The Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) system was used to grade the evidence quality. We included 34 RCTs involving 3086 patients. Results indicated that compared with the controls, acupuncture and moxibustion resulted in significantly lower scores on the THI, achieved a significantly higher efficacy rate, reduced scores on TEQ, PTA, VAS, HAMA and HAMD. The meta-analysis revealed that acupuncture and moxibustion have a good safety profile in the treatment of primary tinnitus. The results showed that acupuncture and moxibustion for primary tinnitus yielded the greatest decrease in tinnitus severity and improvement in quality of life. Due to the low quality of GRADE evidence grade, the considerable heterogeneity among trials for several data syntheses, more high-quality studies with large sample sizes and longer follow-up periods are urgently needed.