A four-year prospective cohort study of 161 patients with moderate glaucoma revealed that patients’ ability to complete vision-related tasks such as recognizing faces, walking and identifying moving objects worsened at a rate similar to decline in visual acuity and contrast sensitivity.

Patients enrolled in the study completed an ocular exam, an automated visual field, OCT and contrast sensitivity testing. The researchers generated mixed-effect models to estimate the rate of change of each variable (retinal nerve fiber layer thickness, IOP, pressure difference between eyes, contrast sensitivity scores) over time.

The researchers found that patients’ ability to complete vision-related tasks was strongly correlated with changes in bilateral visual acuity. Changes in retinal nerve fiber layer thickness and visual fields didn’t correlate strongly with any vision-related performance or vision-related quality of life measures. A worse symptom stage was associated with worse visual acuity.

The researchers concluded that for glaucoma patients, performance-based tests correlate strongly with clinical variables, particularly contrast sensitivity. “These findings suggest that contrast sensitivity, quality of life and functional tests are useful in evaluating the progression of glaucoma,” they noted.