RESUMEN
Aim: To investigate the longitudinal change in central corneal thickness (CCT) over 3 years in patients with glaucoma. Materials and Methods: The Chennai Glaucoma Follow‑up Study, an offshoot of the Chennai Glaucoma Study, was designed to evaluate the progression of glaucoma. A cohort of participants in the Chennai Glaucoma Study that were suffering from glaucoma or were at a higher risk for glaucoma underwent comprehensive ophthalmic evaluation at the base hospital at 6‑month intervals during the years 2004 to 2007. The CCT (average of 10 readings) was measured between 11 am and 1 pm on any given day using an ultrasonic pachymeter. Patients with a history of ocular surgery, corneal disease and usage of topical carbonic anhydrase inhibitor were excluded. No patient was a contact lens wearer. Results: One hundred and ninety‑six patients (84 male, 112 female) met the inclusion criteria. We analyzed data from the right eye. The mean age of the patients was 59.97 ± 9.06 years. Fifty‑nine (30.1%) of the patients were diabetic. The mean change in CCT (CCT at first patient visit – CCT at last patient visit) was 3.46 ± 7.63 µm. The mean change in CCT was 0.75 µm per year (R2 = 0.00). Age, gender, intraocular pressure at the first patient visit and diabetic status had no significant influence on the magnitude of change in CCT. Conclusion: A carefully obtained CCT reading by a trained examiner need not be repeated for at least 3 years as long as the ocular and systemic factors known to affect the measurement of CCT are constant.
RESUMEN
Aim: To assess the awareness and knowledge levels about glaucoma and its determinants in an urban population of Chennai in south India. Materials and Methods: Chennai glaucoma study (CGS) was a population based prevalence study to estimate the prevalence of glaucoma in a rural and urban south Indian population. A total of 3850 subjects aged 40 years or above participated in the urban arm of CGS. A systematic random sample of 1926 (50.0%) subjects completed a questionnaire that assesses their awareness and knowledge level of glaucoma. Respondents “having heard of glaucoma” even before they were contacted/recruited for the study were defined as “aware” and respondents having some understanding of the eye disease were defined as “knowledgeable”. Results: Overall 13.5% were aware of glaucoma, the age-gender adjusted rate for awareness was 13.3% (95% CI: 11.57 to 15.03). Two clinicians graded knowledge on glaucoma, based on the subject's knowledge of risk factors, definitions and treatment aspects of glaucoma. Overall 8.7% had some knowledge about glaucoma. Among those who had knowledge 0.5% had good knowledge about glaucoma, 4% had fair knowledge and 4.2% had poor knowledge. We observed a very good agreement between the clinicians in grading knowledge (k =0.92). Determinants of glaucoma awareness and knowledge were higher levels of education, females, age, religion and family history of glaucoma. Conclusion: Awareness and knowledge about glaucoma was very low among the urban population of Chennai. We have found that younger subjects and men were less aware of glaucoma. Subjects with lower levels of education were less aware and knew less about glaucoma than their counterparts. The study findings stress the need for health education for effective prevention of blindness due to glaucoma.