Effect of estrogen and progesterone therapy on intraocular pressure: a systematic review and meta-analysis study

This systematic review and meta-analysis aimed to assess the effect of Hormone Replacement Therapy (HRT) with estrogen and progesterone on Intraocular Pressure (IOP) in postmenopausal women, with the objective of determining whether HRT can lower IOP and potentially reduce glaucoma risk. Following PRISMA guidelines, a comprehensive search was conducted up to June 2024. Eligible studies included randomized controlled trials and observational studies that reported IOP changes in postmenopausal women undergoing HRT. The pooled mean differences in IOP were calculated using both random-effects and fixed-effect models. The meta-analysis included 9 studies with a total of 1,024 participants. The pooled analysis showed a significant reduction in IOP among women receiving HRT compared to controls, with a mean difference of 3.84 mmHg (95% CI: 2.26 to 5.41, p < 0.01) in the random-effects model, and 2.36 mmHg (95% CI: 2.08 to 2.64, p < 0.01) in the fixed-effect model. Despite these significant results, there was high heterogeneity across studies (I² = 97%), likely due to variations in hormone types, dosages, and treatment durations. HRT is associated with a significant decrease in IOP in postmenopausal women, potentially offering protective benefits against glaucoma, although further research is needed to address the observed variability.