Finding the sweet spot surrounding the number of anti-glaucoma medications translates to a balancing act with focus on individual patient needs.
This article was reviewed by Janet B. Serle, MD
Ophthalmologists have the luxury of choosing from among seven current IOP-lowering medications, with doses that range from one to four times daily. The list includes prostaglandin analogs (PGAs), rho kinase inhibitors, beta-blockers, alpha-agonists, carbonic anhydrase inhibitors (CAIs), miotics, and non-selective adrenergic agonists.
This may well be an embarrassment of riches, with the ready availability of these options raising interesting questions and prescribing quandaries for physicians.
Likely the most important question is what is the optimal tolerated, effective, and reasonable IOP-lowering regimen? Janet B. Serle, MD, pointed out during a presentation at the 2019 American Academy of Ophthalmology annual meeting.
“We have a great deal of evidence-based facts about medical therapy,” she said. “We know that if a second, third, fourth, or more medications are added to a regimen, typically effective IOP reductions are not anticipated/obtained compared with when those medications are used as first-line interventions.”
Dr. Serle, professor emeritus, Icahn School of Medicine at Mount Sinai, New York, noted that the duration of efficacy of a second, third, fourth, or more medications may be less and the efficacy tends to wane over time.
Other factors come into play that reduce patient compliance, such as regimen complexity, cost, side effects, age, physical infirmity, changes in mental status, education level, and health literacy. The nighttime efficacy is also less with some drugs, resulting in possible glaucoma progression. Inter-day and intra-day IOP fluctuations also can result in progression.
A study has suggested that combination therapy may actually reduce fluctuations. Chronic medical therapy causes changes in conjunctival tissue that may negatively impact incisional surgery, and chronic drug dosing contributes to ocular surface disease, Dr. Serle enumerated.
While numerous caveats are related to the decisions to prescribe IOP-lowering medications, Dr. Serle noted that the question is what actually has been happening in medical practice.
A look-back at treatment practices shows a steady rise in the average numbers of medications prescribed over the past three decades. The average number in the Advanced Glaucoma Intervention Study in 1992 indicated that 2.7 drugs were prescribed.
This was prior to the advent of the PGAs, topical CAIs, and adrenergic agonists. When those drugs became commercially available, the average number of medications rose to 3.0 and 3.2 in major studies from the late 1990s to 2004.
By 2006, the average was 3.4, and the current regimens reported in peer review articles have included 3.6 medications; CME case reports have reported use of three to five medications in individual patients, Dr. Serle reported.