Smell Dysfunction in Patients with Primary Sjögren’s Syndrome: impact on quality of life

Abstract

Abstract Objectives Patients with primary Sjögren’s Syndrome (pSS) often report smell and taste disturbance. However, a correlation between the smell impairment and mucosal dryness is not well understood. The objectives of this study were to investigate: 1) The prevalence of smell hypofunction in patients with SS. 2) The impact of smell hypofunction on the quality of life (QoL) 3) Whether the smell is corelated to xerostomia. 4) Whether the smell function is affected by taste hypofunction, disease duration, age, smoking or with self-reported neuropathy. Methodology: An ethically approved cross-sectional study was conducted on 65 female patients with SS and 62 sex-matched healthy controls. The smell was assessed using the University of Pennsylvania Smell Identification Test. The taste acuity was assessed using Taste Strips Test. Visual analogue scale was used for self-assessment of the smell and taste functions. Xerostomia was assessed by salivary flow rate, the clinical oral dryness score and Xerostomia Inventory. The QoL and mental health well-being were assessed using validated questionnaires. Results In the SS group, the smell function was impaired in 27/65 compared with controls (15/62 p < 0.05) and it did not correlate with the severity of xerostomia, taste acuity (r = 0.05, p = 0.6) or with the self-reported nasal dryness (r=-0.02, p = 0.7). In the patients group, the smell hypofunction was not correlated with disease duration (β = 0.1, 95% CI=-0.07-0.1), or smoking (β=-0.02, 95% CI=-8-7). Age was not correlated with the smell function in the patients’ group (β=-0.1, P = 0.5), but correlated significantly with the smell in the healthy participants group (β=-0.3, P = 0.02). Neuropathy affected 81.2% of the patients group. The QoL and mental health well-being were not affected by the smell hypofunction. Conclusion Smell hypofunction appears to be a clinical manifestation in patients with SS, but it does not seem to be associated with the severity of mucosal dryness or with taste disturbance.