Association between tear film break up time and blink interval in visual display terminal users

AIM：To investigate the association between tear film break up time（TBUT）and blinking interval in visual display terminal（VDT）users.METHODS：Nine hundred and thirty VDT users underwent dry eye testing,and functional visual acuity（FVA）test.The blinking interval during FVA was compared with TBUT.Subjects with longer blinking interval than TBUT were considered as unstable tear film.Logistic regression analysis revealed the risk factors for unstable tear group.RESULTS：Among 930 workers,858 subjects（92.3%）participated in this study.Almost 80% of the subjects were categorized into the unstable tear group.Unstable tear group has significantly lower Schirmer values and TBUT（17.5±11.6 vs 21.1±11.5 mm,3.7±2.6 vs 5.7±2.7s,both P〈0.001）.There were no significant differences in epithelial staining or severity of symptoms.Logistic regression showed that over 40y was a risk for being unstable tear group[odds ratio（OR）=1.53;95%confidence interval（CI）=1.06-2.20].Contact lens use was protective factor for being in the unstable tear group（OR=0.37;95%CI=0.26-0.53）.CONCLUSION：Subjects with shorter TBUT than blinking interval are prevalent among VDT users.Subjects over the age of 40 shows an increased risk for unstable tear film.

Prevalence and risk factors of dry eye disease in young and middle-aged office employee:a Xi’an Study

AIM:To estimate the prevalence of and risk factors for dry eye disease(DED)in young and middle-aged office employee in Xi’an.METHODS:This cross-sectional study of the prevalence of and risk factors for DED investigated 486 young and middle-aged Chinese office employee in Xi’an.DED symptoms and potential risk factors were assessed using the ocular surface disease index combined with a risk factors questionnaire,and tear function was evaluated using the tear film break-up time and Schirmer’s test.Possible risk factors for DED were estimated by binary Logistic regression analysis.RESULTS:DED was diagnosed in 100 females and 96 males,giving a prevalence of 40.3%[95%confidence interval(CI)=36.0%-44.7%].The multivariate binary Logistic regression model indicated that the possible risk factors for DED were being female(OR=1.592,95%CI=1.034-2.451,P=0.035),being aged≥40 y(OR=1.593,95%CI=1.034-2.454,P=0.035),using a VDT daily for>6 h(OR=1.990,95%CI=1.334-2.971,P=0.001),the presence of central air conditioning(OR=1.548,95%CI=1.053-2.276,P=0.026),and self-reported dryness of the mouth and nose(OR=1.589,95%CI=1.071-2.357,P=0.021).CONCLUSION:There is a high prevalence of clinically diagnosed DED in young and middle-aged video displayterminal(VDT)users.Interventions against the modifiable risk factors should be taken to prevent the occurrence and development of DED in this population.