Traditional Chinese medicine for olfactory dysfunction: A bibliometric analysis of published clinical studies

Objective: Olfactory dysfunction (OD) defined as a disease of smell disorders. Studies have suggested that traditional Chinese medicine (TCM) is effective for OD. A bibliometric analysis on TCM for OD was conducted to identify trends and potential hot topics. Methods: 11 databases were searched from their inception to Sep 4, 2024 for all types of clinical studies on TCM for OD. Data were extracted and analyzed using Excel 2016 and R Studio data collected included study characteristics, type of diseases, treatments, comparisons, outcomes, effictiveness, and adverse events. The quality of all randomized controlled trials (RCTs) was evaluated using the “Revised Cochrane risk-of-bias tool”. Results: Of 412 studies published from 1963 to 2024, there were 10 systematic reviews, 255 RCTs, 16 non-RCTs, 80 case reports, 47 case series, 3 cohort studies, 1 case controlled study. OD can be caused by a variety of diseases. The most common disease was chronic rhinosinusitis. And the most common OD was hyposmia. The top three common TCM treatment modalities were TCM decoction, acupuncture, and Chinese patent medicine. The most common used herb and acupoint were “Xin Yi (Magnolia Flower)” and “Yingxiang (LI 20)”. Most RCTs reported positive effects of TCM for OD. No severe adverse events related to TCM were reported. The quality of overall RCTs was low. Conclusions: At present, the research hotspots of TCM for OD mainly focus on OD caused by upper respiratory tract infection, TCM decoction internal use and acupuncture in therapy.