Ocular Surface in Patients With Obstructive Sleep Apnea Syndrome: Evaluation of Clinical Parameters and Impression Cytology

PURPOSE: To evaluate the effect of obstructive sleep apnea syndrome (OSAS) on the ocular surface and conjunctival cytology and the relationship between the findings and disease severity. METHODS: One hundred six eyes of 106 patients (77 patients with OSAS and 29 control subjects) were included in the study. Twenty-three patients with an apnea-hypopnea index (AHI) of 5 to 15 were classified as mild OSAS (group 1), 27 patients with an AHI of 15 to 30 were classified as moderate OSAS (group 2), and 27 patients with an AHI≥30 were classified as severe OSAS (group 3). The following tests were used to evaluate the ocular surface: tear break-up time (TBUT), Schirmer I test, ocular surface disease index (OSDI), and conjunctival impression cytology (CIC). The results obtained from the tests were analyzed and compared between the groups. RESULTS: The mean value of the Schirmer I test was 15.03±10.16 (1-35) mm in the control group, whereas it was found as 13.39±8.80 (3-35) mm, 9.85±7.81 (1-30) mm, and 9.41±7.53 (2-35) mm in the mild, moderate, and severe OSAS groups, respectively, and the difference between the groups was significant ( P =0.002). Although the mean TBUT score was 9.83±5.03 (3-23) seconds in the control group, it was 11.04±6.22 (3-20), 6.26±3.48 (1-16), and 5.44±3.09 (1-10) in the mild, moderate, and severe OSAS groups, respectively, and the difference between the groups was significant ( P <0.001). Although the mean OSDI score was 12.76±14.84 (range, 0-41.65) in the control group, it was 11.52±12.95 (range, 0-44.40), 25.06±19.45 (range, 0-75), and 20.31±19.87 (range, 0-77.70) in the mild, moderate, and severe OSAS groups, respectively, and the difference between the groups was significant ( P =0.015). Although the mean CIC stage was 0.47±0.60 (0-2) in the control group, it was 0.89±0.74 (0-2), 1.52±0.75 (0-3), and 1.83±0.69 (1-3) in the mild, moderate, and severe OSAS groups, respectively, and the difference between groups was significant ( P <0.001). CONCLUSION: In addition to decreased tear production and TBUT, cytological changes including squamous metaplasia were detected between patients with OSAS and the control group.