Abstract
Purpose :
Oral contraceptives have been associated with an increased risk of cardiovascular disease, ischemic stroke and venous thromboembolic disease. Retinal vascular occlusions share several risk factors with cardiovascular and cerebrovascular disease. The purpose of this study was to determine if exposure to female hormonal therapy (FHT) increases the risk of retinal artery occlusions (RAO) and retinal vein occlusions (RVO).
Methods :
A retrospective cohort study was conducted to compare women enrolled in a national insurance plan who filled a prescription for female hormonal therapy between 2002 to 2016 who were matched up to 5:1 to unexposed controls. Exclusion occurred for enrollment for <2 years in the plan, previous RAO or RVO, no prior ophthalmologic exam, exposure to medications that effect estrogen levels or presence of a systemic disease associated with altered estrogen levels. The primary outcome was the incidence of a new diagnosis of RAO or RVO. To account for possible differences between the exposed and unexposed cohorts, a propensity score for FHT exposure was created and inverse probability of treatment weighting (IPTW) was used. Weighted Cox proportional hazards regression modeling estimated hazard ratios (HR) for RAO or RVO relative to FHT exposure. Sub-analyses were conducted to stratify the data by age, race, diabetes mellitus (DM), and hypertension (HTN).
Results :
A total of 190,099 FHT-exposed patients were matched to 730,449 unexposed controls. There were 43 (0.01%) cases of RAO and 66 (0.02%) cases of RVO in the FHT cohort. In comparison, there were 414 (0.06%) cases of RAO and 640 (0.09%) cases of RVO in the control cohort. After inverse probability of treatment weighting (IPTW), Cox regression analysis showed no difference in hazard for RAO, RVO or combined outcomes in the FHT-exposed cohort relative to the unexposed group [RAO HR=1.06, 95% CI: 0.77-1.46; RVO HR=1.02; 95% CI: 0.78-1.33; Combined HR=1.01; 95% CI: 0.81-1.25, p>0.73]. After stratification by age, DM and HTN, no significant associations were found between FHT-exposed versus unexposed for RAO, RVO or the combined outcome (p>0.27 for all comparisons).
Conclusions :
Exposure to female hormonal therapy was not associated with an increase in retinal artery occlusions or retinal vein occlusions.
This is a 2020 ARVO Annual Meeting abstract.