Five-year incidence of open-angle glaucoma: the visual impairment project.
OBJECTIVE
To determine the incidence of open-angle glaucoma (OAG) in Melbourne, Victoria, Australia.


METHODS
Population-based cohort study.


METHODS
Total of 3271 participants aged 40 years and older from Melbourne, Victoria, Australia.


METHODS
Five-year incidence of OAG.


METHODS
Participants were recruited through a cluster random sampling from nine urban clusters. Baseline examination was conducted from 1992 through 1994, and the follow-up data were collected from 1997 through 1999. Each participant both at baseline and follow-up underwent a standardized ophthalmic examination including intraocular pressure measurement, visual field assessment, cup-to-disc ratio measurement, and paired stereo photographs of the optic disc. Glaucoma was assessed by a consensus group of six ophthalmologists that included two glaucoma specialists. Glaucoma was diagnosed as possible, probable, or definite.


RESULTS
The overall incidence of definite OAG was 0.5% (95% confidence limits [CL], 0.3, 0.7); probable and definite incidence of OAG was 1.1% (95% CL, 0.8,1.4); and possible, probable, and definite OAG incidence was 2.7% (95% CL, 1.8, 3.7). The incidence of possible, probable, and definite OAG increases significantly as age increases (P < 0.001). The incidence of definite OAG increases from 0% of participants aged 40 to 49 years to 4.1% of participants aged 80 years and older. The incidence of probable and definite OAG increases from 0.2% of participants aged 40 to 49 years to 5.4% of participants aged 80 years and older. The incidence of possible, probable, and definite OAG increases from 0.5% of participants aged 40 to 49 years to 11% of participants aged 80 years and older. A nonsignificant but higher incidence of definite OAG among men was observed in this study when compared with women (odds ratio, 2.2; 95% CL, 0.9, 5.9). Fifty percent of the definite OAG participants were undiagnosed.


CONCLUSIONS
The incidence of OAG increases significantly with age. The undiagnosed cases suggest the need to develop novel community screening strategies for glaucoma.
Mukesh
Bickol N
BN
Centre for Eye Research Australia, the University of Melbourne, Melbourne, Victoria, Australia. mukeshbn@unimelb.edu.au
McCarty
Catherine A
CA
Rait
Julian L
JL
Taylor
Hugh R
HR
D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D003941:Diagnostic Techniques, Ophthalmological; D005260:Female; D005902:Glaucoma, Open-Angle / Q000175:diagnosis / Q000453:epidemiology*; D006801:Humans; D015994:Incidence; D007429:Intraocular Pressure; D008297:Male; D008875:Middle Aged; D011897:Random Allocation; D014505:Urban Population / Q000706:statistics & numerical data; D014739:Victoria / Q000453:epidemiology; D014794:Visual Fields; D019987:Persons with Visual Disabilities / Q000706:statistics & numerical data