The Effects of Systemic Antihypertensives on Change in Intraocular Pressure After Initiating Topical Prostaglandin Therapy for Open Angle Glaucoma

Abstract

Purpose : There is a limited understanding of the factors that influence the efficacy of topical glaucoma medication. Our study is a long-term, case-control analysis of how systemic antihypertensive (antiHTN) medication may influence change in intraocular pressure (IOP) after initiating glaucoma drop therapy.

Methods : A retrospective chart review of 3781 patients was performed on patients with a diagnosis of Glaucoma Suspect that progressed to Open Angle Glaucoma (OAG) by ICD-9 codes over a 10-year period. The inclusion criteria consisted of the following: 1) progression from pre-glaucoma to glaucoma diagnosis in a timespan greater than 6 months, 2) two visual fields recorded between these dates, 3) initial average IOP of both eyes of 21 mmHg, and 4) initiation of topical prostaglandin (PG) therapy alone. Charts were evaluated for demographic data, hypertension (HTN) diagnosis, systemic medications and IOP measurements (in mmHg) at the date of initiating PG drops. IOP was then recorded at the next visit.

Results : 111 patients qualified for analysis. Of these, 43.2% were male and 56.8% were female. 58.6% were Caucasian, 34.2% were Hispanic, and 7.2% were of another ethnicity. 59.5% of patients had a previous HTN diagnosis, while 40.5% did not. The age range of patients was 38-94 years (median=70, mean=68.7).
Mean pre-treatment IOP (taken as an average of both eyes) was 24.28, with a range of 21-31. The mean IOP after therapy was initiated was 17.34 (range=10.5-28). Mean decrease in IOP after initiation of therapy was 6.63, or 27.6%. Patients were evaluated based on whether they were on antiHTN agents and if they were on multiple HTN agents. 40 patients were on a single antiHTN agent, 31 were on multiple antiHTN agents, and 40 on no antiHTN agents.
Patients not on antiHTN agents had an average IOP decrease of 6.95. Comparatively, patients on antiHTN agents had an average IOP decrease of 6.98 (p=0.6068). In addition, there was no statistically significant difference between IOP decrease between patients on single vs. multiple systemic antiHTN agents (p=0.8547).

Conclusions : No statistically significant difference exists between systemic antiHTN medication use and efficacy of IOP reduction in patients treated with topical PG for OAG. No evidence was found to support an impact of systemic antiHTN therapy on the efficacy of topical PG therapy for OAG.

This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.