Abstract
Purpose: :
To compare the prevalence and severity of dry eye in patients having Rheumatoid arthritis (RA) with age and sex–matched controls in the Indian population using the Schirmer’s test and tear film breakup time (TBUT) on slit lamp examination.
Methods: :
A cross–sectional study was performed between May and November, 2004 in the Department of Ophthalmology, KEM Hospital, Mumbai on 84 eyes of 84 adult patients with well documented RA (based on the American Rheumatology Association criteria) and 84 eyes of 84 age and sex–matched controls. Mc Monnie’s dry eye questionnaire was used to classify the patients based on their symptoms. Dry eye was diagnosed if the wetting on Schirmer’s filter paper test was <=10mm after 5 minutes (with topical anesthesia) and tear film breakup time was <10 seconds on slit lamp examination using fluorescein. Student’s t test was used to compare mean wetting on Schirmer’s test and mean TBUT between the 2 groups. The prevalence of dry eye in the two groups was found based on the above criteria using the Schirmer's test and TBUT.
Results: :
41% of patients with RA had dryness based on Schirmers’s test as compared to 12% in the age and sex matched control group. The mean wetting obtained on the Schirmer’s filter paper in the former group was 16mm (SD=7.93mm) and in the latter group 29mm (SD=10.8mm). 22.62% of patients with RA had TBUT <10 sec on Slit lamp examination, compared to 3.57% of controls. The patients of RA had a mean TBUT of 12.4 seconds (SD=4.41s). The control group had a mean TBUT of 18.9 seconds (SD=5.98s). The difference in the mean wetting (p=0.031) and mean tear film breakup time (p=0.007) between the two groups was significant. It was found that ocular symptoms such as itching, dryness, grittiness and foreign body sensation had no particular relation to the results of Schirmer’s test and tear film breakup time. Among the patients with RA, additional findings were– 2 patients had evidence of corneal filaments on slit lamp examination, 1 patient had corneal ulceration and scarring as a result of the decreased tear production and 3 patients had evidence of uveitis. None of the controls had any evidence of complications or associated conditions.
Conclusions: :
Patients with RA in the Indian population may have a significantly higher prevalence and severity of dry eye when compared to age and sex matched controls, and should undergo regular ocular examination to detect it and prevent complications. Furthermore, ocular symptoms may have a limited correlation with the occurence of dryness in these patients.
Keywords: cornea: tears/tear film/dry eye • clinical (human) or epidemiologic studies: prevalence/incidence • autoimmune disease