Olfactory dysfunction in primary Sjogren’s syndrome and its correlation with dry eye

OBJECTIVE: To evaluate the olfactory function in primary Sjögren’s syndrome (pSS) patients and investigate its correlation with dry eye parameters. METHODS: Thirty-eight pSS patients (49.47 ± 10.06 years) and 20 healthy volunteers (47.40 ± 8.92 years) were enrolled in the study. All participants underwent ENT and eye examinations including a modified Connecticut Chemosensory Clinical Research Center (CCCRC) test, tear break-up time (TBUT), ocular surface staining (OSS) and Schirmer test. The parameters were compared between the two groups using Student-t test, and Pearson test was used to evaluate the correlations. RESULTS: Mean Schirmer and TBUT values were 2.39 ± 1.48 mm/5 min and 3.66 ± 1.5 sec in pSS and 18.30 ± 6.16 mm/5 min and 14.60 ± 3.64 sec in healthy subjects (p < 0.001, both). There was a significant decrease in mean odour threshold, odour identification, CCCRC and VAS scores in the pSS group (p < 0.001). Dry eye parameters showed moderate correlations with CCCRC parameters (r = 0.4-0.6, p < 0.001) and olfaction VAS score (r = 0.4-0.75, p < 0.05). CONCLUSIONS: There is a mild clinical impairment in smell sense in patients with pSS which seems to be correlated with dry eye parameters. Therefore, smell complaints should be queried in pSS patients suffering from severe dry eye.