Abstract
Objective: The objective of this study was to evaluate the efficacy of hangekobokuto in chronic tinnitus.
Study design: This study was a randomized, double-blind, placebo-controlled trial compared hangekobokuto to placebo in chronic tinnitus patients.
Setting/location: This study was conducted at the Department of Otorhinolaryngology of Kitasato University Hospital/Japan.
Subjects: Participants were adults, with chronic ( ≥ 3 months), mild to severe handicap (Tinnitus Handicap Inventory [THI] score ≥ 18).
Interventions: Seventy-six patients were randomized to receive either hangekobokuto or placebo.
Outcome measures: Change in THI score from baseline to final follow-up visit was the primary efficacy measure. Changes in Visual Analog Scale (VAS), Hospital Anxiety and Depression Scale (HADS), and Short-Form 36-Items Health Survey (SF-36) scores were secondary efficacy measures. We also conducted 3 ancillary analyses.
Results: No significant intergroup differences were noted in THI (Total: p = 0.73, Functional: p = 0.99, Emotional: p = 0.78, Catastrophic: p = 0.59), or any secondary endpoints. In patients without apparent anxiety or depression, no significant intergroup differences were noted in THI. In patients with vertigo/dizziness, hangekobokuto tended to improve THI (Total: p = 0.006) as compared to the placebo. In patients with hangekobokuto "sho", no significant intergroup differences were noted in THI.
Conclusion: Although no significant intergroup difference was observed, hangekobokuto tended to improve THI in patients with vertigo/dizziness. Identifying a more definitive indicator for prescribing Kampo medicine and a study design which reflects characteristics of Kampo medicine may lead to a more informative evaluation of its benefit.
