Despite the increase in glaucoma medication use recorded in several other developed countries, researchers found that topical intraocular pressure (IOP)-lowering medication use in the United States remained stable from 1999 to 2014, which they note may be due to the differential performance of other procedures.

Researchers conducted a series of eight nationally representative surveys of United States residents every two years from 1999 to 2014, asking adults over age 40 if they have used or taken a prescribed medication in the past month. The team found no change in the number of Americans using topical IOP-lowering medications, with 1.4% of survey takers on the medications between 1999 and 2000, as well as 2013 and 2014. They note that while the number of drugs per patient remained unchanged, there was a significant increase in the use of prostaglandin analogs and combination medications and a decrease in the use of beta-blockers.

“The United States experience appears to be different from other nations in not having either an increase in the number of residents on topical IOP-lowering medication or an increase in the number of medications per user,” the study authors wrote. “This effect is particularly remarkable as Medicare part D was implemented in 2006 in the middle of this study period and increased the coverage for prescription drugs among Medicare beneficiaries.”

Lowry EA, Chansangpatch S, Lin SC, et al. Use of topical intraocular pressure lowering medications in the United States population: results from the NHANES study 1999-2014. J Glaucoma. June 24, 2019. [Epub ahead of print].