The biggest question in glaucoma care is: When do you start treatment?
|This newly diagnosed patient has a large optic disc with a thin neuroretinal rim. We started her on a prostaglandin. Would a laser procedure have been preferable?
The next biggest question: Which treatment is right for this patient?
To answer the latter, we have to consider many factors: the class, brand and concentration of medication; the cost; the frequency of dosage; and the patient’s ability to comply with the treatment plan. And that only takes medication into account. What about laser therapy?
Remember, of course, that treatment is only a means to an end. Our goal is to save as much vision as possible, within the overall context of the patient’s health, quality of life and life expectancy.
To that end, my usual approach for a typical newly diagnosed patient with primary open-angle glaucoma (POAG) is to begin intervention as early as possible in the course of the diagnosis, with a goal of a 30% reduction in intraocular pressure. All treatment should be individualized, of course; but as a general rule, 30% is a good goal to shoot for.
This percentage comes from a literature review of several landmark randomized clinical trials—such as the Ocular Hypertension Treatment Study, Early Manifest Glaucoma Trial, Collaborative Normal-Tension Glaucoma Study and Advanced Glaucoma Intervention Study—as the best initial target to halt and slow down further progression of the disease for a newly diagnosed patient.1 However, target pressure is a dynamic parameter, so more advanced POAG patients may require a greater (40% to 50%) IOP reduction.
Now, what treatment can best accomplish that 30% reduction? We have some options to consider.
In glaucoma care, medical therapy has been the first-line treatment of choice among U.S. eye doctors because it’s a conservative, relatively cost-effective therapy. (Is medicine still the go-to treatment? More on that later.)
In my practice, I place most of my newly diagnosed patients on IOP-lowering drops, typically a prostaglandin. But I also individualize care for my patients to meet our common goals and determine a treatment that is effective, safe, well tolerated and affordable for them.
We have a number of factors to consider just within medical therapy:
• Convenience. Convenience may sound inconsequential when weighed against the possibility of losing sight, but we cannot discount its importance. It stands to reason that convenience facilitates compliance, which ultimately helps to preserve vision.
Of course, the most convenient option is a prostaglandin analog, which affords once-a-day therapy along with excellent IOP reduction. On the flip side, a prostaglandin can be a challenge for some patients with arthritis to instill because of the bottle’s small size.
• Cost. As with convenience, cost ties into compliance. Just as patients will extend the wear of their two-week contact lenses to four weeks, they’ll stretch out the use of their pricey drops by skipping every other day, or using the drug even less frequently.2
No recent studies compare the current costs of these medications; but, just as an example, a quick call to Walgreens (a popular pharmacy chain in my area) found that a 5ml bottle of Lumigan (bimatoprost 0.01%, Allergan) retails for $272, Travatan Z 5ml (travoprost, Alcon) is $235, and Timoptic 5ml (timolol maleate 0.25%, Aton Pharma) is $115. Bear in mind that prices vary depending on the pharmacy.
Cost is less of a concern for patients who have a pharmacy benefit plan. The copayment for a brand-name tier 2 prostaglandin can range from $25 to $45. For a generic tier 1 medication, such as timolol, the copayment is likely to be in the $5 to $15 range. Meanwhile, pharmacies in big-box stores, such as Target, Costco and Walmart, routinely offer generics for just $4. (See “Give the Option of a Generic.")
• Compliance. We know that the majority of glaucoma patients, especially newly diagnosed ones, are not compliant with their medicine at least some of the time. As many as two out of three patients who are new to ocular hypotensive therapy have a “substantial gap” in refilling their drops in the first year of therapy.3
To make matters worse, even existing patients incorrectly instill their drops anywhere from 66% to 90% of the time.4,5 Along these lines, non-compliant patients include those with severe arthritis and manual dexterity problems, or with other physical or mental limitations, such as dementia or Alzheimer’s, that impede their ability to properly instill an eye drop. For these patients, I consider a treatment that works every day, all day long—laser trabeculoplasty.
Which should be our current first-line option for the newly diagnosed patient: medical therapy or laser treatment? Our clinical practice guidelines specify that medical treatment has been the traditional approach; however, our protocol recognizes that other treatments, such as laser trabeculoplasty, also offer significant benefits.6 (Here, I’ll use the term laser trabeculoplasty, or LTP, to encompass both selective laser trabeculoplasty and argon laser trabeculoplasty.)
Like medical therapy, LTP requires us to consider factors of convenience, cost and compliance:
• Convenience. LTP avoids the inconvenience and necessity of instilling glaucoma drops one or more times a day. More than this, by reducing IOP about as effectively as a prostaglandin, LTP is a good strategy for an intervention that will minimize progression.7
On the other hand, it’s not a slam dunk, neither for effectiveness nor convenience. That’s because the procedure’s effect diminishes over time (about three to five years), and may require a repeat procedure and/or adjunctive medication.
• Cost. This is the jackpot question: Which is the most cost-effective method to treat our patients—ongoing medical therapy or essentially a one-time treatment with laser?
A recent article attempted to answer just that.8 Researchers used a mathematical model to compare cost effectiveness of treating newly diagnosed open-angle glaucoma patients with a prostaglandin, LTP or observation only.
Interestingly, they found that prostaglandins and LTP are both cost-effective treatment options for this patient population. However, when patients have “optimal medication adherence,” then prostaglandin therapy is a better value than LTP. Yet, as we know, patients are more likely to be noncompliant than compliant with therapy. Given this reality, the researchers concluded, LTP may be a more cost-effective alternative than prostaglandins at current prices.8 For instance, Medicare reimburses physicians about $336 for LTP. The patient’s responsibility is 20% of that, unless they have supplemental insurance. Copayment and other deductibles may also apply.
• Compliance. LTP essentially removes the issue of compliance. Indeed, it can be an effective solution when patients on medical therapy become noncompliant—especially those patients with physical or mental limitations, as mentioned above, as well as patients on two or more medications.
While compliance can be spotty for a glaucoma patient on one topical medication, it worsens when you add a second drop.9 So, LTP plays a great role as an adjunctive therapy or second-line treatment option.
Choices at Chairside
So what does all this mean for the patient in your chair?
For me, it means that I’m going to start the vast majority of my newly diagnosed patients on medical therapy. I’m going to offer the patient the option of a generic vs. a branded product. I’m going to discuss compliance, cost and all those “real world” considerations. I’m going to follow them regularly (every three to four months) and continue to ask open-ended questions about how they’re doing with their medications—cost and otherwise. Remember that patients who show progression, yet have good “in-office” IOP, might be noncompliant between visits.
|Give the Option of a Generic
Many doctors have the impression that
generic ophthalmic medications are not manufactured to the same
standards as brand-name drugs, and are therefore inferior. But for
ophthalmic solutions at least, the generic manufacturing standards must
be essentially the same.
“Currently, generic ophthalmic solutions,
such as latanoprost, are expected to have the same active and inactive
ingredients in the same concentrations. If they are not the same, then a
study comparing the clinical bioequivalence has to be performed,”
explains Wiley Chambers, M.D., the FDA’s Deputy Director for the
Division of Transplant and Ophthalmology Products.11
Generic latanoprost became available in
March 2011, and several manufacturers now produce it. In my experience,
the price ranges from $30 to more than $70 a bottle. (At the Walgreens
near me, it retails for $78.) I often recommend the brand-name
medication, but I also offer my patients the option of a generic. I make
sure to explain to them that their formulary plan may cover a
brand-name product. I tell them I’ve been using these branded products
for many years and I’m very familiar with their safety and efficacy. On
the other hand, I explain that the generically available prostaglandin
is virtually the same as the brand-name drug. Then I simply ask them
My patients are split. Some are perfectly
comfortable with generics because they take generic systemic
medications, so they have no qualms about taking a generic ophthalmic
medication. Others just don’t believe in a generic; they want the
brand-name drug, and nothing else will do.
And lastly, for patients who would benefit from it, I now know that laser trabeculoplasty is a safe and cost-effective alternative to medical therapy. As the recent study indicates, if my patient is not compliant with a prostaglandin, then I offer the option of LTP.8
Occasionally, I offer LTP as a first-line therapy—perhaps in 10% to 15% of newly diagnosed patients. They are patients who do not appear to be compliant with medical therapy right from the start. (Other glaucoma providers may offer SLT as a first-line option. That’s fine, as long as patients are given all the pros and cons of both medical and surgical options. In my opinion, I prefer to begin with a prostaglandin, because it will continue to work for years as long as the patient is reasonably compliant. I usually reserve LTP until I need it.)
What does the future hold? Unfortunately, no breakthrough glaucoma medications are on the horizon; however, investigators are working on longer-lasting drug delivery systems—via contact lenses, punctal plugs, nanoparticles and subconjunctival or intravitreal injections and depots—to overcome the compliance conundrum.
In the meantime, we must continue to talk to our patients about the importance of regular therapy. Right now, about 2.7 million American adults have glaucoma—a 22% increase since 2000—and that number is only going to grow, according to a recent report from Prevent Blindness America.10 This calls attention to how important it is that we persist in our care of glaucoma patients, and it highlights the opportunity (and the challenge) we have in front of us.
Dr. Chaglasian is an associate professor at Illinois College of Optometry and chief of staff of the Illinois Eye Institute, in Chicago.
1. Singh K, Shrivastava A. Early aggressive intraocular pressure lowering, target intraocular pressure, and a novel concept for glaucoma care. Surv Ophthalmol. 2008 Nov;53 Suppl1:S33-8.
2. Kennedy J, Morgan S. A cross-national study of prescription nonadherence due to cost: data from the Joint Canada-United States Survey of Health. Clin Ther. 2006 Aug;28(8):1217-24.
3. Reardon G, Kotak S, Schwartz GF. Objective assessment of compliance and persistence among patients treated for glaucoma and ocular hypertension: a systematic review. Patient Prefer Adherence. 2011;5:441-63.
4. Stone JL, Robin AL, Novack GD, et al. An objective evaluation of eye drop instillation in patients with glaucoma. Arch Ophthalmol. 2009 Jun;127(6):732-6.
5. Gupta R, Patil B, Shah BM, et al. Evaluating eye drop instillation technique in glaucoma patients. J Glaucoma. 2012 Mar;21(3):189-92.
6. Fingeret M, Mancil GL, Bailey IL, et al. Optometric Clinical Practice Guideline: Care of the Patient with Open Angle Glaucoma. 2nd ed. St. Louis, MO: American Optometric Association; 2011:39-62.
7. McIlraith I, Strasfeld M, Colev G, Hutnik CM. Selective laser trabeculoplasty as initial and adjunctive treatment for open-angle glaucoma. J Glaucoma. 2006 Apr;15(2):124-30.
8. Stein JD, Kim DD, Peck WW, et al. Cost-effectiveness of medications compared with laser trabeculoplasty in patients with newly diagnosed open-angle glaucoma. Arch Ophthalmol. 2012 Apr;130(4):497-505.
9. Robin AL, Novack GD, Covert DW, et al. Adherence in glaucoma: Objective measurements of once-daily and adjunctive medication use. Am J Ophthalmol. 2007 Oct;144(4):533-40.
10. Prevent Blindness America. Vision Problems in the U.S. June 20, 2012. Available at:
www.visionproblemsus.org/glaucoma.html. Accessed June 22, 2012.
11. American Academy of Ophthalmology/ONE Network website. Questions About Generic Ophthalmic Medications. September 2011. Available at:
http://one.aao.org/asset.axd?id=bd41e411-cedc-4992-9ed5-4b3f60dafc18. Accessed June 22, 2012.