Acupuncture for olfactory dysfunction in infected COVID-19 patients: Study protocol for a randomized, sham-controlled clinical trial

Background: Olfactory dysfunction (OD) is a common symptom of Corona Virus Disease 2019 (COVID-19). It is defined as the reduced or distorted ability to smell during sniffing (orthonasal olfaction) and represents one of the early symptoms in the clinical course of COVID-19 infection. A large online questionnaire-based survey has shown that some post-COVID-19 patients had no improvement 1 month after discharge from the hospital. Objective: To explore the efficacy of acupuncture for OD in COVID-19 infected patients and to determine whether acupuncture could have benefits over sham acupuncture for OD in post-COVID-19 patients. Methods: This is a single-blind, randomized controlled, cross-over trial. We plan to recruit 40 post-COVID-19 patients with smell loss or smell distortions lasting for more than 1 month. Qualified patients will be randomly allocated to the intervention group (real acupuncture) or the control group (sham acupuncture) at a 1:1 ratio. Each patient will receive 8 sessions of treatment over 4 weeks (Cycle 1) and a 2-week follow-up. After the follow-up, the control group will be subjected to real acupuncture for another 4 weeks (Cycle 2), and the real acupuncture group will undergo the 4-week sham acupuncture. The primary outcomes will be the score changes on the questionnaire of olfactory functioning and olfaction-related quality of life at week 6, 8, 12, and 14 from the baseline. The secondary outcomes will be the changes in the olfactory test score at week 6 and 12 from the baseline measured by using the Traditional Chinese version of the University of Pennsylvania Smell Identification Test (UPSIT-TC). Discussion: The results of this trial will help to determine the effectiveness of acupuncture for OD in post-COVID-19 patients. This may provide a new treatment option for patients.