Quality of Life in Glaucoma Detectable Via OCT, Visual Field Testing

Quality of life in glaucoma can be predicted using optical coherence tomography (OCT) independent of visual field (VF) testing, according to research published in the Journal of Glaucoma. Lower retinal nerve fiber layer (RNFL) thickness measured by OCT is associated with reduced measures of functionality for patients with glaucoma when ceiling and floor effects are accounted for, researchers report.

The researchers evaluated 156 patients diagnosed with glaucoma or suspected glaucoma to determine if OCT measures such as RNFL thickness and macular ganglion cell/inner plexiform layer (GICPL) thickness correlate with and predict measures of disability. 

Following primary analysis, mean GICPL and RNFL thicknesses across all stages of glaucoma correlated with self-reported Glaucoma Quality-of-Life 15 (GQL-15) and Fear of Falling (FOF) scores but this association did not persist after accounting for VF damage. OCT measures additionally were not associated with functional tests results such as reading speed or steps per day.

In a post-hoc analysis, researchers accounted for ceiling and floor effects using a subpopulation of participants with thickness estimates between 55 µm and 75 µm — the range expected to correlate with changes in function. 

The post-hoc analysis showed that within this range, RNFL thickness but not GICPL thickness was significantly associated with the quality of life in glaucoma questionnaire (RNFL: CI, –2.65 to –0.51 per z-score unit difference in RNFL thickness; P =.004; GICPL: CI, –1.23 to +0.46 per z-core unit difference in GICPL thickness; P =.37) and FOF scores (RNFL: CI, –6.26 to –0.86 per z-score unit difference in RNFL thickness; P =.01; GICPL: CI, –3.41 to +1.62 per z-core unit difference in GICPL thickness; P=.48). This association persisted when accounting for central or peripheral VF damage.

These data suggest that both OCT and VF independently predict patients quality of life in glaucoma. Thus, RNFL thickness could be used to inform clinical management for some patients.

“When limited to the range of thicknesses expected to affect function, RNFL was associated with both QoL and FoF independent of both central and peripheral VF losses. As such, RNFL thickness may inform clinical management in selected glaucoma patients,” the researchers report.

The study was limited by a small sample size of patients with better eye RNFL and GICPL thicknesses between 55 and 75 µm.