BACKGROUND
 Diabetic retinopathy and early development of cataracts are well-known ocular complications of long-standing diabetes. In recent years various researchers have reported ocular surface disorders, particularly dry eyes in diabetic patients which if left untreated may result in a variety of corneal complications. These ocular surface disorders can be clinically diagnosed by performing a detailed slit lamp examination, Schirmer's test and tear film break-up time. Our study intended at assessing tear film and ocular surface disorders in diabetic patients and study tear film function in them and compare it with non-diabetic patients.
 METHODS
 A comparative cross-sectional study was done on 100 diabetic and 100 non-diabetic patients > 30 years of age visiting OPD of health centre of tertiary care hospital of Central India. Clinical data and detailed clinical history were obtained from all subjects through direct patient interviews and reviewing of their medical records followed by a comprehensive ocular examination that included best-corrected vision, slit lamp examination, and Tear Film break up time (TBUT) & Schirmer test.
 RESULTS
 In our study, mean TBUT was found to be significantly reduced in diabetics (15.94 ± 3.8) as compared to non-diabetics (20.13 ± 6.6). No significant difference was found in the Schirmer test reading between diabetics (17.13 ± 3.20) and non-diabetics (19.20 ± 6.23). Diabetic male patients had significantly decreased mean TBUT & mean Schirmer test readings as compared to diabetic females. Mean Schirmer reading & Mean TBUT were lowest in a patients having > 20 years of DM and highest in patients having < 5 years of DM. No positive correlation was found between HbA1c (Glyosylated Haemoglobin) and diabetic retinopathy with TBUT/ Schirmer test readings.
 CONCLUSIONS
 Our study showed that the tear film stability was found to be affected in diabetic patients, as compared to non-diabetic subjects as evident by the lower level of TBUT in diabetic patients. Significantly reduced TBUT with no significant difference in Schirmer test reading in diabetic as compared to non-diabetic subjects might be due to a decrease in basal secretion with normal overall tear secretion. The absence of subjective symptoms of dryness in spite of decreased TBUT in the diabetic group might be due to a decrease in corneal sensitivity caused by diabetic peripheral neuropathy in diabetic patients. There was an increase in the prevalence of DES with an increasing duration of DM. Rheumatoid arthritis was found to be a risk factor for DES. Diabetic males were found to be at risk for developing dry eye syndrome. Hence it can be concluded from our study that every diabetic patient should undergo a comprehensive eye examination which should include various tests for dry eye assessing multiple tear parameters.
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