Female hormone therapy not linked to retinal vascular occlusion; JAMA Ophthalmology

The interesting findings have been published in JAMA Ophthalmology.

Female hormone therapy (FHT) includes oral contraceptive pills (OCPs) in women of reproductive age and hormone therapy in postmenopausal women. It is well documented that Oral contraceptives are associated with cardiovascular disease, ischemic stroke, venous thromboembolic disease, and breast cancer. Retinal vascular occlusions share the same risk factors as cardiovascular and cerebrovascular disease. To date, numerous case reports have associated oral estrogen use with developing RVO or RAO.

To have a in-depth understanding on this topic, researchers undertook a study to determine whether filling a prescription of female hormone therapy (FHT) is associated with an increased risk of retinal artery occlusion (RAO) or retinal vein occlusions (RVO).

For the study design,a multiple-cohort study was conducted using an administrative claims insurance database comparing women who filled a prescription for FHT with matched control individuals. Exclusion occurred for those enrolled for less than 2 years in the plan, with no prior ophthalmologic examination, with a history of a RAO/RVO, with systemic diseases/medications that affected estrogen levels, or a disease associated with an increased risk for thromboembolism.

The primary outcome was the incidence of a new diagnosis of RAO or RVO. Subanalyses were conducted to stratify by age, race/ethnicity, diabetes, and hypertension.

A total of 205 304 women who filled a prescription for FHT were matched to 755 462 control individuals. After inverse probability of treatment weight, the study cohort was a mean age of 47.2 years, 71% were White, 7% were Black, 6% were Hispanic, 3% were Asian, and 3% were unknown.

On analysis, the following facts emerged.

• There were 41 cases (0.01%) of RAO and 68 cases of RVO (0.02%) in the FHT cohort. In comparison, there were 373 cases of RAO (0.05%) and 617 cases of RVO (0.08%) in the control cohort.
• After inverse probability of treatment weight, Cox regression analysis showed no difference in hazard for RAO, RVO, or combined outcomes in the FHT cohort relative to the control cohort (RAO HR, 1.17; 95% CI, 0.83-1.65; P = .36; RVO HR, 1.07; 95% CI, 0.82-1.39; P = .65; combined HR, 1.10; 95% CI, 0.89-1.36; P = .37).
• Subanalyses that stratified by age, diabetes, and hypertension similarly showed no significant associations between the FHT prescription cohort and all outcomes.

"Despite many forms of oral contraceptives and female hormonal therapy being recognized as a risk factor for thromboembolisms,9,12,14,28 these hormones do not appear to affect the eye as they do in other areas of the body" wrote the team.Primary source:JAMA Ophthalmology

For full article follow the link: 10.1001/jamaophthalmol.2020.4884