Correlation between clinical and cytological parameters of dry eye among diabetics in a Nigerian tertiary hospital

Abstract

Purpose To correlate the clinico-cytological features of dry eye among diabetic patients attending Lagos University Teaching Hospital, Lagos. Methods This was a cross-sectional, comparative study among 104 diabetic and 104 age-/sex-matched non-diabetic participants. Demographics were obtained using interviewer-administered questionnaire. Ocular Surface Disease Index (OSDI) questionnaire was used for subjective assessment of dry eye. All participants underwent ocular examination and dry eye assessment including Schirmer I test, tear film break-up time (TBUT) and ocular surface staining. In addition, conjunctival impression cytology (CIC) samples were taken for histological assessment. Data were analysed using IBM Statistical Package for the Social Sciences version 20.0 (IBM Corp., Armonk, NY USA). Results The mean age was 58.5 ± 10.05 years and 58.32 ± 10.48 years among the diabetics and non-diabetics, respectively (p = 0.856). The male/female ratio was 1:1.4. Three hundred and ninety-seven (199 diabetic and 198 non-diabetic) eyes were assessed. Diabetics had a significantly higher median OSDI score and ocular surface staining grade compared to non-diabetics (p = 0.002 and 0.005, respectively). The TBUT was slightly lower, while the Schirmer test was slightly higher among the diabetics, but not significant (p = 0.058 and 0.033, respectively). The diabetics had a significantly higher CIC grade (p < 0.001). There was a moderate positive correlation between conjunctival cytology and ocular surface staining (r = 0.50, p < 0.01). Conclusion This study demonstrates worse ocular surface damage among diabetics characterised by ocular surface staining and abnormal CIC. Furthermore, it shows a positive correlation between ocular surface staining and CIC. Dry eye assessment should be incorporated in routine diabetic eye screening.