Tear film measurements in four different ethnic groups: Malay, Chinese, Indian and Nigerian

Abstract

AIM: To compare the non-invasive tear film break-up time(NIBUT), tear break up time(TBUT), basal tear secretion(BTS)and blink rate in four ethnic groups: Malay, Chinese, Indian and Nigerian.METHODS: Totally 120 healthy(61 males and 59 females)subjects(without dry eye symptoms and ocular surface disorder)with the age 20 to 39 years were recruited; 30 were Malays, 30 were Chinese, 31 were Indians and 29 were Nigerians. Based on McMonnies questionnaire and clinical examination, normal subjects were selected. NIBUT, TBUT, BTS were assessed in only one eye(right)of each subject and blink rate was also assessed.RESULTS: There was significant difference in the NIBUT, TBUT, BTS and blink rate among 4 different ethnic groups(P=0.018),(P=0.001),(P=0.011), and(P=0.004)respectively. No statistically significant difference of NIBUT, TBUT, BTS and blink rate was found between the genders among different ethnic groups. Indian had higher median for NIBUT(10±6s), TBUT(7±5s)and BTS(20±20 mm)than others races. Chinese had lower median for NIBUT(7.5±4s)and TBUT(4±2s)while Malay had low BTS(9.5±16 mm)among the groups. There was no significant correlation of blink rate with NIBUT, TBUT and BTS(r= -0.119, P=0.195),(r=-0.086, P=0.352),(r= -0.123, P=0.180)respectively.CONCLUSION: This study showed the variability in tear-film measurements values in four ethnic groups.

Keywords

• non-invasive tear film break-up time
• tear break-up time
• basic tear secretion
• blink rate and ethnicity