To determine whether abnormalities in the function of the autonomic nervous system are associated with oral and ocular dryness in rheumatoid arthritis.
Pupillography was done using an infrared light reflection method (IRIS) to measure both parasympathetic function (constriction latency and the latency of maximum constriction velocity (MCV)) and sympathetic function (dilatation latency) in rheumatoid arthritis patients with and without ocular dryness. The Schirmer and Saxon tests were used to measure the tear and saliva production respectively.
The Schirmer and Saxon test results in rheumatoid arthritis patients with ocular dryness were reduced (P < 0.05) compared with rheumatoid arthritis patients without ocular dryness and healthy controls. Constriction latency and MCV latency were prolonged in rheumatoid arthritis patients with ocular dryness compared to the other two groups (P < 0.05). A negative correlation was found between the degree of ocular dryness and both constriction latency and MCV latency. No correlation was found between the results of pupillography and saliva production.
Parasympathetic dysfunction may play a role in ocular dryness in patients with rheumatoid arthritis.