Use of Topical Intraocular Pressure-lowering Medications in the US Population: Results From the NHANES Study 1999 to 2014.

We found no evidence of an increase in the number of Americans using topical intraocular pressure (IOP) medication or a number of drops used per patient from 1999 to 2014, although there were significant changes in the class of medications used.The purpose of this study was to determine changes in topical IOP-lowering medication use in the United States from 1999 to 2014.A series of 8 nationally representative, weighted cross-sectional surveys of United States residents were performed every 2 years from 1999 to 2014. On 2-year cycles, professional interviewers performed in-home interviews of a representative sample of the nation as part of the National Health and Nutrition Examination Survey study. Participants were asked, "In the past month, have you used or taken medication for which a prescription is needed?" Adults over age 40 who responded to this question were included in the analysis. The primary outcome was number of US adults using topical IOP-lowering medication. Secondary outcomes included the number and types of medications used.There was no change in the number of adults using topical IOP-lowering medications over the time period studied (P=0.74) with 1.4% (95% confidence interval: 0.9%-1.8%) of US residents on IOP-lowering medications in 1999 to 2000 and 1.4% of US residents (95% confidence interval: 1.1%-1.8%) on topical medications in 2013 to 2014. There was no change in the number of medications per patient over the period of the study (P=0.14). There was a significant increase in the use of prostaglandin analogs and combination medications and a decrease in the use of β-blockers (all P<0.01).In contrast to the increase in glaucoma medication use seen in several other developed nations, use in the United States remained stable from 1999 to 2014. This may be due to differential use of other procedures. Future studies of IOP-lowering medications incorporating the effect of new agents and minimally invasive surgeries are warranted.