The Ocular Hypertension Treatment Study: Aging and Reliability of Visual Fields

Abstract

Purpose : To determine if visual field reliability declines as participants age in the Ocular Hypertension Treatment Study (OHTS).

Methods : The OHTS enrolled 1,636 participants between 1994-1996. To be eligible, patients were required to have two normal, reliable Humphrey 30-2 full threshold VF’s in both eyes on baseline. In addition, VF technicians were required to be certified per protocol. The Visual Field Reading Center (VFRC) evaluated each VF for quality control using a 100-point scale. VF’s were completed every six months until close-out in 2009. In 2016, OHTS was funded to conduct a 20-year follow-up study to determine the quality of life and visual functioning of participants. VF testing protocol remained constant throughout the study.

We report the percent of participants with > 33% fixation loss at 12 years and at 22 years following baseline VF’s. One eye of each participant was selected randomly with preference given to the eye that developed primary open-angle glaucoma. We did not assess false positive or false negative rates because the algorithms changed during the study. Participants who returned for f/up but could not perform VF testing are assumed to have “excessive fixation losses” and are reported separately.

Results : To date, 47% (546 of 1,156) of the presumed survivors have completed VF testing. Twelve participants returned to the clinic but were unable to complete VF testing due to a physical/cognitive condition. The median time from baseline VF testing was 22 years.

The rate of excessive fixation losses was higher in each age decade older with sample size > 100. The rate of excessive fixation losses increased faster in older decades over the 22 year f/up.

Conclusions : The rate of excessive fixation loss was higher with older age in OHTS. The rate of fixation loss in OHTS likely underestimates the rate of fixation loss in a busy clinic secondary to our rigorous VF protocol requirements for patients and technicians, in addition to real-time quality monitoring by the VFRC.

This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.