Managing Glaucoma During Pregnancy

Commentary

In the article in the August issue of the Archives of Ophthalmology, Brauner et al¹ address the important topic of glaucoma during pregnancy. In their review of the clinical course of 28 eyes of 15 pregnant women with glaucoma, the authors report that progression of glaucoma or elevation in the intraocular pressure occurred in 10 eyes (35.7%). All but 2 patients were treated with antiglaucoma medications during the pregnancy, although 1 patient (2 eyes, 7.1%) was nonadherent. No adverse effects related to the use of these medications were noted either among the mothers or their offspring. Despite the small number of patients in this case series, the evidence suggests that most of women with glaucoma can be treated effectively during pregnancy. However, continued close follow-up of the disease process during and after pregnancy is warranted.

This article raises several important issues. First, in an era of evidence-based approaches to medical care, a retrospective case series is not considered a high level of evidence. However, given that performing a randomized controlled trial involving expectant mothers with glaucoma would not be feasible, this level of evidence will need to suffice. This limitation also highlights the critical importance of coordination of care and communication between clinicians about individual patients. Ophthalmologists caring for pregnant women must be aware of the literature regarding the safety of specific antiglaucoma medications. Similarly, primary care clinicians and obstetricians must be cognizant of the potential systemic absorption of topical ophthalmic medications, such as adrenergic antagonists, adrenergic agonists, and topical carbonic anhydrase inhibitors. Ideally, these clinicians should be in communication about their shared care responsbilities for the care of these patients. For example, the authors of this study reminded their patients to perform punctual occlusion following administration of topical eye medications to reduce systemic absorption. However, this message must be reinforced by all clinicians involved in the care of pregnant women.

Second, the level of evidence and the communication among and between physicians caring for pregnant women are critical underpinnings for the confidence the patient should have in the treatment plan. The reality is that the current evidence is insufficient to establish that these antiglaucoma drugs are absolutely safe among pregnant women. Most of the ophthalmic drugs used by the women in this study were pregnancy category C, which indicates that studies in animals have demonstrated adverse effects on the fetus, but clinical evidence among humans is lacking. Thus, physicians must communicate honestly with their patients about what is known, as well as what is unknown about these treatments. When patients decide to discontinue antiglaucoma medication, as one patient did in this study, they must be reminded to continue to follow-up so that other interventions can be initiated if and when they may be needed.

And third, this study reaffirms the role that sex plays in the management of patients with ocular disease. The importance of sex should be underscored not only with regard to the observation of ocular hypotension during the course of pregnancy, but also the potential effect of early menopause and risk of glaucoma, and the greater risk of disease progression among women who have low tension glaucoma. However, the literature is unclear as it relates to sex and glaucoma.² For example, in a survey of more than 5000 women exploring the relationship between female reproductive factors and eye disease in South India, investigators failed to identify a relationship between cataract, myopia, macular degeneration, or open angle glaucoma, and the age at menopause and parity.³ On the other hand, Lee et al⁴ reported a modest relationship between parity and glaucoma in the Blue Mountains Eye Study.

To clinicians, these questions may seem academic, particularly when the unpredictability of disease processes is considered. For example, 5 eyes in the study by Brauner et al¹ exhibited elevated intraocular pressures during pregnancy. Regardless of the lack of conclusive data, the influence of reproductive factors should at least be considered as a possible contributing factor. It was not too long ago that sex differences were considered unimportant with regard to stroke and heart disease—2 disease processes that now have well documented differences in outcome related to the sex of the affected individuals.⁵

The study by Brauner et al¹ provides an opportunity to consider the larger questions in medicine, such as the evidence on which clinical decisions are based; the importance of communication between and among physicians, as well as communication between physicians and patients; issues of nonadherence and sex-related factors in clinical care; and the imperative to individualize treatment approaches for each patient. These are issues that clinicians face daily, but remain elusive for epidemiologists and clinician-scientists.