Abstract 195: Evaluation of Dry Eyes in Hypothyroid patients in comparison to Euthyroid subjects

Purpose: To evaluate tear function test (OSDI questionnaire, Schirmer's Test and TBUT) and corneal surface disorder (Impression cytology) in recently diagnosed hypothyroid patients and to compare results with healthy subjects. Setting/Venue: Mahatma Gandhi Medical College, Jaipur, Rajasthan, India. Methods: Cross sectional analytical study. 30 recently diagnosed (within 3 months of diagnosis) patients of hypothyroidism and 30 healthy age matched controls were included. All patients and controls underwent assessment of proptosis, Palpebral fissure-height (PFH), tear function test (OSDI questionnaire, Schirmer's test and Tear Break-up-time (TBUT) and Impression Cytology for ocular surface assessment. These parameters were compared between cases and controls. Standard statistical analysis was used. Results: Mean Proptosis and PFH showed no significant difference among groups (P value =.071). Mean value of OSDI was 41.15+16.03 & 29.33+6.84 in hypothyroid & Controls respectively, the difference being statistically significant (P=.001). Mean TBUT was 6.38+2.46 sec and 11.15+2.39 sec in hypothyroidism & controls respectively (P=0.001). Mean value of Schirmer tear test was 13.30+4.44mm, and 17.55+7.35mm in Hypothyroidism and controls respectively (P=0.001). 70% of patients in hypothyroidism group had grade 2-3 squamous metaplasia as compared to 24.4% in controls, signifying ocular surface damage (P<0.05). Conclusions: Mean PFH and proptosis did not differ between two groups. However, increased OSDI score, decreased Schirmer's test value, decreased TBUT & grade 2-3 squamous metaplasia in patients of thyroid dysfunction suggests presence of dry eyes. Despite no clinically visible signs of thyroid ophthalmopathy, there is ocular surface damage right from the early stages of thyroid dysfunction. This is attributable to evaporative mechanism as well as ocular surface inflammation & hyperosmolarity of tear film.