OPEN-ANGLE GLAUCOMA AND DIABETES - THE BLUE MOUNTAINS EYE STUDY, AUSTRALIA

Purpose: The authors explore the relationship between diabetes and ope n-angle glaucoma in a defined older Australian population. Methods: Th ree thousand six hundred fifty-four people 49 to 96 years of age, livi ng west of Sydney, underwent a detailed eye examination, This included automated perimetry, stereo optic disc photographs, and applanation t onometry; in addition, fasting plasma glucose levels were ascertained. Glaucoma was diagnosed if matching visual field and optic disc cuppin g were present, without reference to intraocular pressure (IOP) level. Ocular hypertension (OH) was diagnosed if IOP in either eye was great er than or equal to 22 mm and glaucomatous disc and visual field chang es were absent. Results: Glaucoma prevalence was increased in people w ith diabetes, diagnosed from history or elevated fasting plasma glucos e level (5.5%), compared with those without diabetes (2.8%; age-gender adjusted odds ratio [OR] 2.12, 95% confidence intervals [Cl] 1.18-3.7 9). Ocular hypertension was also more common in people with diabetes ( 6.7%), compared with those without diabetes (3.5%; OR 1.86, Cl 1.09-3. 20), Diabetes was present in 13.0% of people with glaucoma, compared w ith 6.9% of those without glaucoma, This increase was highest for prev iously diagnosed glaucoma cases (16,7%; OR 2.82, Cl 1.35-5.87). Howeve r, in 67% of such cases, glaucoma was diagnosed before the diabetes. F or those not receiving glaucoma treatment, IOP was consistently slight ly higher in people with diabetes, with the age-gender adjusted mean I OP 0.6 mm higher. Conclusions: The significant and consistent associat ion between diabetes and glaucoma found in our study, which appeared i ndependent of the effect of diabetes on IOP, suggests that there is a real association between these two diseases.