Treatment of progressive myopia needs to begin as early as possible
Drug shortage, including ophthalmic eye drops, is becoming a meaningful problem for doctors and patients, especially for generic eye drops in which there is minimal financial incentive to the manufacturer.
At present, there are 189 drugs listed on the U.S. drug shortage list. Ophthalmology is well represented, with 14 commonly used drugs listed. These include office diagnostic agents such as Fluress (fluorescein and benoxinate), tropicamide and cyclopentolate to important therapeutics including bacitracin ophthalmic ointment, injectable anesthetics such as lidocaine and even timolol solution and timolol gel. Fortunately, there are often alternative agents, such as tropicamide in place of cyclopentolate, but at present, both of these important drops are on the U.S. drug shortage list. In most cases, the preferred drug can be obtained from a specialty compounding pharmaceutical company, and these sources are empowered to manufacture and distribute any drug in shortage.
The therapy of progressive myopia is a hot topic today, and we have covered it in previous cover stories. I was interested to learn that even relatively low myopia is associated with significant comorbidity. The –2 D myope has a two times increase in cataract, a four times increase in glaucoma, a three times increase in retinal detachment and a two times increase in myopic maculopathy. At –2 D to –6 D, cataract risk is magnified three times, glaucoma four times, retinal detachment nine times and myopic maculopathy 10 times. Higher than –6 D, what many call pathologic myopia, cataract is increased five times, glaucoma 14 times, retinal detachment 22 times and myopic maculopathy 41 times.
Just like in glaucoma, in which we have learned that every millimeter of mercury increase in IOP is important and increases the risk for glaucoma and glaucoma damage, it appears that in myopia, every diopter of myopia matters and increases the risk for sight-threatening comorbidities. So, to me, progressive myopia is not benign and deserves to be treated. Treatment includes behavior modification with increased outdoor activity and exposure to natural sunlight along with rest periods when doing near work as prescribed by the 20/20/20 rule. Optical correction is important, and patients should be fully corrected with monofocal spectacles or contact lenses. Specialty eyeglasses and contact lenses are coming into the market with supporting data, and orthokeratology is an option.
Pharmaceutical intervention is today possible with low-concentration atropine. Fortunately, accumulating data from around the world confirm that very low-dose atropine is equally effective as higher concentrations in reducing the rate of myopia progression. As higher concentrations have more adverse effects including pupillary dilation and reduced accommodation, this is a fortunate finding.
Most experts use 0.01% to 0.03% atropine, with the vast majority choosing 0.01%. It appears that if the atropine eye drops are suddenly discontinued, there is a rebound effect with more rapid myopia progression, so patients should be counseled that long-term therapy is required, in some cases extending 10 to 20 years. This means we need a safe and comfortable application of topical atropine that can be given once a night for years, and several companies are pursuing approval in the United States and globally. For now, 0.01% to 0.05% atropine drops can be obtained from specialty compounding pharmaceutical companies. My sources tell me that as many as 1 million low-dose atropine prescriptions have been written by American ophthalmologists and optometrists to treat progressive myopia, with good acceptance by patients and a low rate of adverse events. Contact allergy is possible, and if this occurs, discontinuation is required.
The challenge, as with any long-term therapy, is compliance. The best results are achieved when myopia is recognized early, and the patient is captured in an eye care provider’s office with continuous follow-up and encouragement. Some pioneers are investigating the pretreatment of children as young as 3 years while they are still hyperopic if there is a strong family history of pathologic myopia. In the future, genetic testing may help us recognize the patient at high risk. As I have mentioned before, a side benefit of capturing these young progressive myopes in an eye care provider’s office and following them closely will be early diagnosis and treatment of keratoconus, reducing the negative impact of that corneal dystrophy on visual function and quality of life.
With the likely approval of a miotic drop to treat presbyopia in the near future, we are entering a new era in which refractive errors are treated with topical ophthalmic pharmaceuticals. I see continuing expansion of this field to the benefit of patients, doctors and the industry that supports us — another triple win for the eye care field.