Abstract
Background
Parosmia is a qualitative olfactory disorder that frequently occurs after infection. Although it often co-exists with partially preserved olfactory function, it can substantially impair quality of life (QoL). The interplay between qualitative and quantitative olfactory dysfunction (OD), and their affective burden, remains unclear. This study examined the specific contribution of parosmia to olfaction-related QoL within a psychophysical-psychological framework.Methods
In this cross-sectional study, 348 patients with OD underwent assessment using the Sniffin' Sticks test (TDI), the Questionnaire of Olfactory Disorders - Positive and Negative Statements (QOD-NS and QOD-PS), and the PHQ-2 for depressive symptoms. Adjusted linear regression models tested main and interaction effects, followed by depression-adjusted analysis.Results
Patients with parosmia were younger and had higher TDI scores than patients without parosmia. Parosmia was associated with poorer olfaction-related QoL (higher QOD-NS) and reduced coping ability (lower QOD-PS). In additive models, parosmia predicted higher QOD-NS and lower QOD-PS, while TDI predicted lower QOD-NS but was not related to QOD-PS. Depressive symptoms were strongly associated with poorer olfaction-related QoL and substantially increased the explained variance of the models. However, after adjustment for depressive symptoms, parosmia remained an independent predictor of both QOD-NS and QOD-PS. Across TDI categories, olfaction related QoL differed by parosmia status, although no interaction between TDI and parosmia was observed.Conclusion
Parosmia represents a distinct and clinically relevant burden on olfaction related QoL that is not explained by quantitative olfactory dysfunction or depressive symptoms. Understanding this independent burden is critical for targeted clinical management.