HealthDay News — During long-term follow-up, about one-quarter of participants in the Ocular Hypertension Treatment study developed visual field loss, according to a study published online April 19 in JAMA Ophthalmology.
Michael A. Kass, MD, from the Washington University School of Medicine in St. Louis, and colleagues examined the cumulative incidence and severity of primary open-angle glaucoma (POAG) after 20 years of follow-up. A total of 1636 participants in the Ocular Hypertension Treatment Study were followed from February 1994 to December 2008. In phase 1 (February 28, 1994, to June 2, 2002), participants were randomly assigned to receive either topical ocular hypotensive medication or close observation. In phase 2 (June 3, 2002, to December 30, 2008), both groups received medication.
The researchers found that 29.5% of participants developed POAG in one or both eyes. The 20-year cumulative incidence of POAG in one or both eyes was 45.6% among all participants after adjustment for exposure time: 49.3 and 41.9% among participants in the observation and medication groups, respectively. The 20-year cumulative incidence of POAG was 55.2 and 42.7% among Black/African American participants and participants of other races, respectively. For visual field loss, the 20-year cumulative incidence was 25.2%. Using a 5-factor baseline model, the cumulative incidence of POAG was 31.7, 47.6, and 59.8% among participants in the low-, medium-, and high-risk tertiles, respectively.
“With only 25% of the individuals in the study developing vision loss in one or both eyes after all these years, we know now that not all of those patients needed to be treated,” Kass said in a statement.
Several authors disclosed financial ties to the biopharmaceutical and medical technology industries.