[Analysis of factors influencing quality of life in patients with olfaction disorders]

Objective: To explore the differences in quality of life among patients with olfaction disorders (OD) due to various etiologies and to identify factors influencing olfactory-related quality of life. Methods: This cross-sectional study enrolled patients with OD who visited the Department of Otolaryngology at Fudan University Eye, Ear, Nose, and Throat Hospital between February and June 2024. Psychophysical olfactory test was performed using the Chinese Smell Identification Test (CSIT), which was based on the Chinese population, with the TDI score used as the total score for threshold (T), discrimination (D), and identification (I) tests. The quality of life related to OD was assessed using a brief version of the Questionnaire of Olfactory Disorders (bQOD), which included QOD-P, QOD-Q, and QOD-VAS. Visual analog scales (VAS) was used to rate the degree of subjective decline in olfaction. Statistical analysis was conducted to assess the impact of etiologies, age, gender, onset time, psychophysical olfactory tests, and subjective assessment on olfactory-related quality of life. Results: A total of 419 patients were enrolled, including 220 males and 199 females, with the age of (39.72±14.31) years (range: 5 to 76 years). Among the 419 patients, 380 completed the bQOD and VAS assessment. The results showed that there were intergroup differences in the QOD-P and QOD-Q scores among patients with OD caused by different etiologies (P values were 0.001 and 0.003, respectively). The QOD-P score was negatively correlated with age (P<0.05), and positively correlated with the TDI score (P<0.01). The QOD-Q score was negatively correlated with disease duration (P<0.05), and positively correlated with the patients' subjective olfactory decline as assessed by the VAS score (P<0.01), and had no significant correlation with psychophysical olfactory tests. Female patients had lower QOD-Q scores than male patients (P<0.05). The QOD-VAS score was positively correlated with the patients' subjective olfactory impairment (P<0.01) and showed no significant correlation with psychophysical olfactory tests. Female patients had worse QOD-VAS scores than male patients (P<0.05). Conclusion: Compared with psychophysical olfactory tests, VAS olfactory scores are more closely related to quality of life. Different etiologies, duration of the disease, and gender also affect olfactory-related quality of life.