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

Area of Science:

• Ophthalmology
• Otorhinolaryngology
• Rheumatology

Background:

• Primary Sjögren's syndrome (pSS) is a systemic autoimmune disease primarily affecting exocrine glands.
• Dry eye disease is a common manifestation of pSS, impacting ocular surface health.
• Olfactory dysfunction has been anecdotally reported in autoimmune conditions.

Purpose of the Study:

• To assess olfactory function in patients with primary Sjögren's syndrome (pSS).
• To investigate the correlation between olfactory parameters and dry eye indicators in pSS patients.

Main Methods:

• A cohort of 38 pSS patients and 20 healthy controls underwent ENT and ophthalmological examinations.
• Olfactory function was evaluated using a modified Connecticut Chemosensory Clinical Research Center (CCCRC) test.
• Dry eye parameters included tear break-up time (TBUT), ocular surface staining (OSS), and Schirmer test.

Main Results:

• pSS patients exhibited significantly reduced Schirmer test values and TBUT compared to controls (p < 0.001).
• Olfactory function, including odour threshold, identification, CCCRC, and VAS scores, was significantly impaired in the pSS group (p < 0.001).
• Dry eye parameters moderately correlated with CCCRC scores (r = 0.4-0.6) and olfaction VAS scores (r = 0.4-0.75).

Conclusions:

• Patients with pSS experience mild olfactory impairment.
• This smell impairment is associated with the severity of dry eye parameters in pSS patients.
• Olfactory complaints warrant consideration in pSS patients presenting with severe dry eye.