The Prevalence of Olfactory Dysfunction and Its Recovery in Chinese Young and Middle-Aged Group COVID-19 Patients

Olfactory dysfunction (OD) is a common symptom of SARS-CoV-2 infection. This study aimed to determine the prevalence and clinical characteristics of OD, evaluate its recovery trajectory, and identify predictors of its onset and persistence.

We conducted a prospective cohort study of 3477 participants recruited through an online questionnaire between December 1 and 31, 2022. Follow-up surveys were conducted over a 12-week period ending on March 31, 2023.

Among 3010 eligible participants aged 14 to 40 years, 373 (12.39%) reported new-onset OD following COVID-19 infection. Multivariable logistic regression identified older age, a history of sinusitis or nasal polyps, prior nasal surgery, and symptoms including fatigue, rhinorrhea, dyspnea, ageusia, and pruritus as independent risk factors for OD. Conversely, fever and arthralgia were negatively associated with OD. The cumulative spontaneous recovery rates were 43.70%, 23.86%, 11.26%, 8.04%, 5.63%, and 1.88% at weeks 1, 2, 3, 4, 8, and 12, respectively. No demographic or clinical variables were significantly associated with recovery time.

COVID-19 related OD occurred in 12.39% of young and middle-aged individuals in China. Several demographic and clinical factors were predictive of OD, although none were associated with recovery duration. Most patients experienced spontaneous resolution within the first month of symptom onset.