Purpose:
As strongly age-dependent conditions, concomitant age-related macular degeneration (AMD) and glaucoma can lead to severe central and peripheral visual loss among elderly. Intraocular pressure (IOP) and ocular perfusion pressure (OPP) have been shown to increase risk for glaucoma. We examined the difference in IOP and OPP in subjects who developed glaucoma through year 10 in the AREDS Study.
Methods:
The publicly available AREDS database was used in analysis. Glaucoma was identified through self report, in which subjects were queried annually as part of a detailed protocol. IOP was calculated as the mean of consecutive study visits with IOP measurements to minimize variability (year 01: visits 01, 03; year 05: visits 09, 11; year 10: 18, 20). The OPP included mean perfusion pressure (MPP, mean arterial pressure - IOP), systolic perfusion pressure (SPP, systolic BP - IOP) and diastolic perfusion pressure (DPP, diastolic BP - IOP); all were calculated from blood pressure measurements taken at visit 10 and the year 05 mean IOP.
Results:
None of the 4116 participants, aged 55-81 and predominantly white, had glaucoma at enrollment. 349 of 3736 (8.5%) participants reported glaucoma through year 10. The mean IOP was statistically significantly higher at years 01, 05 and 10 among 10-year incident glaucoma cases as compared to those who did not develop glaucoma (Table 1). The mean OPP, SPP and DPP were lower in 10-year incident glaucoma cases compared to those without glaucoma, but the difference was not statistically significant (10-year incident glaucoma cases, n = 2113 vs. without glaucoma, n = 210; OPP: 80.3 vs. 81.2, p = 0.27; SPP: 119.2 vs. 120.4, p = 0.37; DPP = 60.9 vs. 61.6, p = 0.31; t-test).
Conclusions:
Crude analyses demonstrate that subjects who self-report glaucoma over the 10-year period had a statistically significantly higher mean IOP throughout the study. The AREDS provides the unique dataset to further investigate factors associated with risks for glaucoma in AMD patients. Future verification of glaucoma diagnoses including assessment of the optic nerves and analyses adjusted for AMD category, treatment category and potential confounders is warranted.
Keywords: clinical (human) or epidemiologic studies: risk factor assessment • aging • age-related macular degeneration