Assessment of autonomic dysfunction in primary Sjögren's syndrome: A combined evaluation using sympathetic skin response and COMPASS 31.

BACKGROUND

Primary Sjögren's syndrome (pSS) is a systemic autoimmune disorder predominantly affecting exocrine glands, with symptoms including dry eyes and mouth. Involvement of the autonomic nervous system (ANS) has been reported, though data on its frequency and clinical significance remain inconsistent. This study aimed to evaluate autonomic dysfunction in patients with pSS using Sympathetic Skin Response (SSR) and the Composite Autonomic Symptom Score 31 (COMPASS 31).

METHODS

Fifty-nine female pSS patients and 38 age-matched healthy controls were enrolled. All participants underwent neurological examination, nerve conduction studies, and SSR testing. Autonomic symptoms were assessed using the COMPASS 31 questionnaire. Disease activity in pSS patients was evaluated with the EULAR Sjögren's Syndrome Disease Activity Index (ESSDAI).

RESULTS

SSR latency and amplitude values were not significantly different between pSS patients and healthy controls. However, total COMPASS 31 scores and all subdomain were significantly higher in the patient group. A strong positive correlation was observed between COMPASS 31 and ESSDAI scores (r = 0.68, p < 0.001).

CONCLUSION

The findings suggest that autonomic symptoms are common in pSS and are associated with disease activity, as reflected by COMPASS 31 scores. However, SSR measurements did not show corresponding abnormalities, possibly due to the absence of vasculitis or ganglionopathy, ongoing treatment. SSR may not be sufficient as a standalone tool to detect autonomic dysfunction in pSS.