Olfactory Function and Disease Severity in Chronic Rhinosinusitis

Abstract

Background Olfactory dysfunction is deemed to be a significant contributor to poor quality of life (QOL). However, little is known about the relationship of olfactory testing to other measures of disease burden in patients with chronic rhinosinusitis (CRS). In this study, we examine the relationship of olfactory function to computed tomography (CT) scores, endoscopy scores, and QOL measures in patients with CRS. Methods A multi-institutional, cross-sectional analysis of 367 patients was performed. Several objective measures were collected: the Smell Identification Test, Lund-MacKay CT score, Lund-Kennedy endoscopy score, two validated disease-specific QOL instruments, the Rhinosinusitis Disability Index and the Chronic Sinusitis Survey, and a general health-related QOL instrument, the Medical Short Form-36. Analysis of variance was performed. Correlation coefficients were calculated. Results Patients with olfactory dysfunction had significantly worse mean endoscopy scores (normosmics, 4.16 [± 3.97]; hyposmics, 6.26 [± 4.21]; anosmics, 9.61 [± 4.48]; p < 0.001) and significantly worse CT scores (normosmics, 9.11 [± 5.40]; hyposmics, 11.16 [± 5.96]; anosmics, 17.62 [± 5.37]; p < 0.001). Endoscopy scores were moderately correlated with olfactory scores (r = -0.46; 95% CI, -0.38, -0.54; p < 0.001). CT scores were moderately correlated with olfactory scores (r = -0.53; 95% CI, -0.45, -0.60; p < 0.001). Olfactory function was not correlated with disease-specific or general health-related QOL measures. Conclusion Although previous studies have suggested that olfactory impairment is associated with poor QOL, this study found no such correlation. In contrast, olfaction scores correlated well with other objective measures of CRS, namely, endoscopy and CT scores.