Abstract
Purpose :
Intraocular pressure (IOP) is the main modifiable risk factor for glaucoma. Current therapies target the anterior outflow of aqueous humor to lower IOP. There are prior studies suggesting a posterior flow mechanism. This study aims to investigate if eplerenone, a mineralocorticoid antagonist, could reduce IOP through a possible posterior outflow path via retinal pigment epithelium (RPE).
Methods :
This retrospective study investigates IOP changes in patients under eplerenone treatment. Inclusion criteria was IOP data immediately before and during eplerenone treatment. Exclusion criteria included ophthalmic procedures, starting or change in topical glaucoma treatment, or taking systemic medications with known effects on IOP. After reviewing 162 charts, 41 subjects were determined to be eligible. A pair sample t-test was used to compare the IOP before and during eplerenone treatment. Pearson correlation test was used to investigate the possible correlation between continuous IOP and eplerenone dosage. A p-value less than or equal to 0.05 was considered statistically significant.
Results :
The mean ± SD IOP before eplerenone treatment was 14.31 ± 3.73 mmHg and decreased to 13.50 ± 4.04 mmHg; however, this was not statistically significant (p = 0.39). There was a weak negative correlation (-0.26) between eplerenone dose and percentage of IOP reduction. In subset of patients with an eplerenone dose of more than 25 mg/day and baseline IOP equal to or less than 15 mmHg, the mean IOP before eplerenone treatment was 12.33 ± 2.59 mmHg and decreased to 10.33 ± 2.99, which is statistically significant (p = 0.05). This equals to a 16% reduction in IOP. In this subset, the correlation between dose and IOP was -0.51.
Conclusions :
The dose-dependent decrease in IOP with eplerenone provides indirect evidence for the posterior flow model and suggests the MRs in RPE play a role in the posterior flow of aqueous humor. It can be deduced that the RPE pumps responsible for the posterior flow of aqueous humor are MR-regulated and their function can be enhanced with MR antagonists.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.