[Tear film function of patients with type 2 diabetes].
OBJECTIVE
To study the tear film function of patients with type 2 diabetes and to investigate the risk factors of dry eye in these patients.


METHODS
Totally 111 patients with type 2 diabetes and 100 age- and sex-matched control subjects were studied. Tear film function was evaluated by dry eye syndrome, tear breaking up time (BUT), corneal fluorescein staining, Schirmer I test (SIt), and tear film lipid layer observation with tear scope. Dye eye score was calculated with the results of these tests.


RESULTS
When compared with the controls, patients with type 2 diabetes showed higher dry eye score (diabetics 3.28 +/- 1.56, control 2.31 +/- 1.50, P < 0.01) and faster BUT [diabetics (6.50 +/- 4.84) s, control (12.26 +/- 7.16) s, P < 0.01], but similar SIt [diabetics (10.61 +/- 6.86) s, control (10.92 +/- 7.05) s, P > 0.05]. More diabetic patients were diagnosed as dry eye(diabetics 19.8%, control 8.0%, P < 0.05). According to their retinopathy, the diabetic patients were divided into three groups: without diabetic retinopathy (DR), with background DR, and with proliferative DR. For these three groups, the dry eye scores were 2.95 +/- 1.50, 3.38 +/- 1.48 and 4.11 +/- 1.60, respectively (P < 0.01); the SIt were (10.95 +/- 6.89) mm, (11.71 +/- 7.30) mm and (7.63 +/- 5.20) mm, respectively (P > 0.05); the BUT were (7.53 +/- 5.23) s, (5.88 +/- 4.10) s and (4.47 +/- 4.17) s (P < 0.05). Patients with DR were then devided into two groups: with photocoagulation and without photocoagulation. For these two groups, the dry eye scores were 4.71 +/- 1.14 and 3.26 +/- 1.15, respectively (P < 0.01); the BUT were (2.93 +/- 2.06) s and (6.26 +/- 4.36) s, respectively (P < 0.01); the SIt were (7.21 +/- 6.51) mm and (11.33 +/- 6.73) mm, respectively (P < 0.05); the rates of corneal fluorescein staining were 50.0% and 17.9%, respectively (P < 0.05). Dry eye score had a good correlation with diabetic retinopathy and photocoagulation (P < 0.01), but was poorly correlaed with age, gender, insulin, duration of diabetes mellitus, and metabolic control (P > 0.05).


CONCLUSIONS
Patients with type 2 diabetes tend to develop tear film dysfunction. The disorders of tear film quantity and quality seem relevant to the stage of diabetic retinopathy and photocoagulation.
Li
Hai-Yan
HY
Department of Ophthalmology, PUMC Hospital, CAMS and PUMC, Beijing 100730, China. lhypumc@sina.com
Pang
Guo-Xiang
GX
Xu
Zhuo-Zai
ZZ
D000328:Adult; D000368:Aged; D003315:Cornea / Q000503:physiopathology*; D003924:Diabetes Mellitus, Type 2 / Q000150:complications / Q000503:physiopathology*; D003930:Diabetic Retinopathy / Q000150:complications / Q000503:physiopathology*; D015352:Dry Eye Syndromes / Q000150:complications / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008028:Light Coagulation; D008297:Male; D008875:Middle Aged; D013666:Tears / Q000378:metabolism