Abstract
Abstract: :
Purpose: The purpose of this study was to determine the impact of race on the variability of risk factors for glaucoma and ocular hypertension in an urban Canadian population. Methods: Study data was gathered during a community based, high risk glaucoma screening clinic conducted in Montreal, Canada between Oct 2003 and Feb 2004. Patients underwent complete ophthalmic examination including visual acuity, corneal pachymetry (CCT), intraocular pressure (IOP) measurement, gonioscopy, slit lamp and dilated fundoscopic examination, as well as imaging of the optic nerve with confocal scanning laser ophthalmoscopy (HRT II). Outcome measures included IOP, CCT, grading of the optic nerve based on the Disk Damage Likelihood Scale (DDLS), HRT parameters (cup/disc ratio, disc area, cup area, rim area , cup/disc area ratio, rim/disc area ratio), as well as Cup Shape Measure (CSM), Height Variation Contour (HVC) and Mean Retinal Nerve Fiber Layer Thickness (MRNFLT). Statistical analyses including student T–tests were performed with SPSS software, and only results that were repeated in both eyes were considered statistically significant. Results: Of 274 patients screened, racial breakdown included 59 Afro–Caribbeans (22%), and 199 Caucasians (72%). Although there was no significant difference between Female/Male ratio between racial groups, Caucasians were significantly older (Mean=66.2 year) than Afro–Caribbeans (Mean=55.1 years), p=0.001. Patients of African–Caribbean descent had statistically significant higher IOP (p<0.001), thinner CCT (p<0.001), greater cup/disc ratio (p=0.016), disc area (p<0.001), cup area (p=0.002), Cup/disc area ratio (p=0.009), and smaller rim/disc area ratio (p=0.009). No statistically significant associations were found between race and CSM, HVC, and MRNFLT. Conclusions: The above results demonstrate that in a Canadian urban setting, African–Caribbean race is associated with an increased number of risk factors for the development of open–angle glaucoma, including a higher IOP, thinner CCT, and larger cup–to–disc and cup–to disc area ratios.
Keywords: clinical (human) or epidemiologic studies: risk factor assessment • imaging/image analysis: clinical