Cognitive Function in Primary Sjögren's Syndrome: A Systematic Review.

Area of Science:

• Neuroscience
• Immunology
• Rheumatology

Background:

• Cognitive disorders are frequently observed in patients with primary Sjogren's syndrome (pSS), sometimes appearing years before diagnosis.
• These neurological manifestations can significantly impact patients' quality of life.

Purpose of the Study:

• To systematically review existing literature on cognitive impairment in pSS.
• To analyze diagnostic methods, and their correlation with laboratory data and clinical features of pSS.

Main Methods:

• A comprehensive literature search was conducted across MEDLINE, EMBASE, and PsycINFO databases up to September 14, 2018.
• Included studies (2002 onwards) assessed cognitive impairment in pSS using AECG classification criteria.
• Data from 18 studies and 3 case reports involving 6196 participants were analyzed.

Main Results:

• Cognitive dysfunction in pSS commonly presents as brain fog or mild cognitive impairment (MCI), with occasional autoimmune dementia.
• The link between pSS and degenerative dementias like Alzheimer's disease remains controversial, though pSS may be a risk factor.
• Significant research gaps were identified, including lack of data on pSS severity, comorbid diseases, and specific dementia types.

Conclusions:

• The current body of research on cognitive function in pSS is limited, with small sample sizes and conflicting results.
• Routine cognitive function assessment in pSS patients is advisable.
• Further well-designed studies are needed to address identified research gaps and improve understanding of cognitive impairment in pSS.