Abstract
Purpose :
To determine the 6-year incidence of primary glaucoma and its risk factors in an Indian population in Singapore
Methods :
The Singapore Indian Eye Study is a population-based cohort study of Indian adults aged between 40 and 80 years living in Singapore. A total of 3,400 subjects participated in the baseline examination between 2007 and 2009 (response rate = 75.6 %). Of them, 2,200 (response rate = 75.5 %) participated in the 6-year follow-up visit between 2012 and 2014. Standardized examination and investigations were performed, including indentation gonioscopy, intraocular pressure measurement, optic disc examination and static automated perimetry. Glaucoma was defined according to the International Society Geographical & Epidemiological Ophthalmology (ISGEO) criteria. Ocular hypertension (OHT) was defined as intraocular pressure (IOP) > 21mmHg and open anterior chamber angles without evidence of glaucoma. Primary angle closure suspect (PACS) is defined as inability to visualize up to the posterior trabecular meshwork in >= 2 quadrants on indentation gonioscopy. Primary angle closure (PAC) is defined as the additional presence of peripheral anterior synechiae, glaucomflecken or IOP > 21 mmHg. Secondary glaucoma was excluded from the analysis. Logistic regression analysis was performed to identify factors associated with the development of primary glaucoma.
Results :
The age-standardized incidences of primary glaucoma, primary open angle glaucoma (POAG) and angle closure glaucoma (PACG) were 2.20% (95% confidence interval [CI] 1.65, 2,92), 1.37% (95% CI, 0.94, 1.96) and 0.32% (95% CI, 0.15, 0.66) respectively. For eyes with OHT (n=45) at baseline, the incidence of POAG was 4.83 % (95% CI, 1.24, 17.21) and for eyes with PAC (n=14)/PACS (n=101), the incidence of developing PACG was 1.82% (95% CI, 0.37, 9.68). The significant risk factors for the development of primary glaucoma were age (relative risk [RR] = 1.67 per decade older [95% CI 1.22, 2.26; P=0.001), IOP (RR=1.22 per mmHg higher [95% CI, 1.11, 1.35]; p<0.001) and cup-disc ratio (RR = 2.03 per 0.1 increase [95% CI, 1.52, 2.72]; p <0.001)
Conclusions :
Our study showed that the overall age-standardized incidence of primary glaucoma was 2.20% in an Indian population in Singapore. In our population, the incidence of POAG was only half of the incidence reported in an Indian population in the Chennai Eye Disease Incidence Study.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.