Classical and Speech Therapy Olfactory Training in the Treatment of COVID-19-Related Olfactory Disorders

BACKGROUND Loss of smell can impair quality of life. Olfactory disorders are often caused by viral infections, including SARS-CoV-2. The aim of the study was to evaluate the effectiveness of a structured, multidisciplinary rehabilitation program, including pharmacological treatment and speech therapy-guided olfactory training, in patients with post-COVID olfactory disorders. MATERIAL AND METHODS A total of 75 patients (15 men, 60 women) were allocated to a study group (n=50) or control group (n=25) using a systematic assignment method. Both groups received the same pharmacological treatment (intranasal corticosteroids and topical vitamin A), saline nasal irrigation, and elements of speech therapy-guided olfactory training. In addition, the study group performed classical olfactory training using 4 odorants twice daily. Olfactory function was assessed using the Sniffin' Sticks Test (SST). RESULTS For the total SST score, the mean change before and after intervention in the study group was 7.9 points (P<0.001). In the control group, the mean change was 2.8 points (P=0.006). CONCLUSIONS Classical olfactory training was associated with greater improvement in post-COVID olfactory disorders compared with pharmacological treatment supplemented with speech therapy-guided olfactory training alone. The observed effects may be related to the combined use of intranasal corticosteroids, topical vitamin A, and saline nasal irrigation; however, the individual contribution of these interventions cannot be determined. The potential contribution of a multidisciplinary approach involving a physician, speech therapist, and psychologist remains to be established.