Most Patients Treated With Laser Trabeculoplasty Are Younger, Female

In general, patients who are prescribed laser trabeculoplasty (LT) as a frontline treatment are typically younger and female, according to findings published in Ophthalmology Glaucoma. Additional characteristics include having no history of previous intraocular surgeries, having lower systemic comorbidity, having a lower socioeconomic status, and living in urban areas.

The research is notable in that, although patients of female sex and those in younger age groups were referred for the procedure more frequently, no research shows significant difference in age or sex between patients who responded to LT and those who did not. In fact, according to the Laser in Glaucoma and Ocular Hypertension trial (LiGHT) study group, female patients are actually more likely to demonstrate poor response to LT at 2-month follow-up exams.

Both selective LT and topical ophthalmic medication are evidence-based first-line therapies for glaucoma, according to the investigators, who took into account both argon laser trabeculoplasty and selective laser trabeculoplasty patients. However, current clinical guidelines don’t provide clear guidance for selecting the appropriate treatment for each patient. 

To investigate which factors are associated with selecting LT instead of topical medications, researchers conducted a population-based study. All patients in the Ontario-based study were 66 years or older and received either LT or topical medication between April 1, 2007, and March 31, 2019, as their first-ever therapy for glaucoma. Patients were excluded if they had undergone a glaucoma procedure in the previous 10 years or had intraocular surgery in the 90 days before beginning glaucoma treatment. 

In total, 194,759 patients were included. The study shows that female patients were significantly more likely than male patients to receive LT (OR, 1.42; 95% CI, 1.39-1.45). However, researchers found that patients were less likely to be treated with LT if they were in the 81 years or older age group than the 66-70 years of age (OR, 0.49; 95% confidence interval [CI], 0.48-0.50). Additionally, those who have undergone  ocular surgeries, including cataract surgery (OR, 0.31; 95% CI, 0.30-0.32), corneal transplantation (OR, 0.39; 95% CI, 0.31-0.49), and retina surgery (OR, 0.46; 95% CI, 0.41-0.51) or those with high comorbidity (highest vs. lowest level of comorbidity: OR, 0.94; 95% CI, 0.91-0.97) were all less likely to receive the LT procedure. This conflicts with other reporting that shows prior surgery is not a predictor of LT efficacy. Investigators report that prior procedures “would not be expected to drive first-line treatment choice.”

The research team also noted that patients with a higher socioeconomic status (highest vs. lowest level: OR, 0.86; 95% CI, 0.84-0.89) and those who live in a rural area (vs urban: OR, 0.92; 95% CI, 0.90-e0.95) were also less likely to receive first-line LT treatment.

“This may reflect a preference for using medications as first-line therapy in situations where monitoring for loss of LT efficacy is challenging because of geographic distance,” the study speculates. “Alternatively, this may be the result of barriers to accessing laser facilities in rural areas.”

Investigators noted an increasing use of LT over the course of the study (for each additional calendar year: OR, 1.05 per year; 95% CI, 1.05-1.05 per year). They also noted several limitations of their study, including the potential for lack of generalizability to other regions, lack of differentiation between glaucoma subtypes, not including provider-level factors that may influence the choice of therapy, and only including patients who were 66 years old or older.

Reference

Quinn MP, Johnson D, Whitehead M, et al. Predictors of initial glaucoma therapy with laser trabeculoplasty versus medication. Ophthalmol Glaucoma. Published online December 21, 2020. doi:10.1016/j.ogla.2020.11.001