Assessing Ganglion Cell Complex Thinning Aids in Predicting QOL in Glaucoma

Robert N. Weinreb, MD

A set of new findings published in JAMA Ophthalmology suggest the assessment of ganglion cell complex thinning may prove to be important in the prediction of vision-related quality of life (VRQOL) in patients with glaucoma.

From the current retrospective analysis of a longitudinal cohort, baseline faster ganglion cell complex thickness changes had an association with lower vision-related quality of life.

“After adjusting for confounding factors, faster GCC thinning and lower visual acuity were associated with a lower VRQOL,” wrote study author Robert N. Weinreb, MD, Shiley Eye Institute, University of California, San Diego. “Specifically, a lower VRQOL was associated weakly with GCC thinning in the 5.6° and 6.8° central macular areas.”

Weinreb and colleagues set out to investigate the potential of a correlation between vision-related quality of life and measurements taken using optical coherence tomography (OCT) imaging, with a specific focus on macular thickness. They evaluated the association between the rate of macular ganglion cell complex (GCC) thinning and VRQOL in a cohort of patients with glaucoma.

In the retrospective analysis, investigators selected all glaucoma-suspect patients and those with primary open angle glaucoma (POAG) enrolled in the Diagnostic Innovations in Glaucoma Study (DIGS) and African Descent and Glaucoma Evaluation study (ADAGES).

The VRQOL was thus evaluated using the 25-item National Eye Institute Visual Function questionnaire, including the 11 subscales: general vision, ocular pain, difficulty with near vision and distance activities, limitations with peripheral vision and color vision, social functioning, driving difficulties, mental health symptoms related to vision, role limitations, and dependence.

The analysis derived ganglion cell complex thickness from macular OCT scans and averaged within 3 circular areas (3.4°, 5.6°, and 6.8° from the fovea) and superior and inferior

hemi regions. Investigators used linear mixed-effects models to investigate the association between their role and Rasch-calibrated vision function questionnaire scores.

A total of 236 eyes of 118 participants, including 72 participants with bilateral POAG and 46 participants with suspected POAG/glaucoma, were included in this analysis. They had a mean age of 73.2 years, while 65 participants (55.1%) were female and 53 participants (44.9%) self-reported as African-American.

Investigators noted the mean composite Rasch-calibrated National Eye Institute Visual Function Questionnaire score was 50.3 (95% CI, 45.9 - 54.6). In the multivariable model, data show a faster annual rate of GCC thinning in the better eye had an association with a higher disability of a composite NEI VFQ score (-15.0; 95% CI, -28.4 to -1.7 per 1 µm faster; P = .03).

Moreover, a faster annual rate of inferior GCC thinning in the better eye was associated with a higher disability of composite NEI VFQ score (-28.4 [95% CI, -49.5 to -7.4] per 1 µm faster; P = .009), although superior was not (-7.1 [95% CI, -16.1 to 1.9] per 1 µm faster; P = .12).

If stratified by degrees from the fovea, investigators found the 5.6” and 6.8” areas were associated with the composite NEI VFQ score (-14.5; [95% CI, -27.0 to -2.0] per 1 µm faster; R2 = 0.201; P = .03 and -23.7 [95% CI, -45.5 to -1.9] per 1 µm faster; R2 = 0.196; P = .02, respectively). Meanwhile, the 3.4” area was -8.0 (95% CI, -16.8 to 0.8) per 1 μm faster (R2 = 0.184; P = .07) after adjusting for confounding factors.

“Understanding how structural changes influence VRQOL is vital for understanding which patients may need more frequent observation and additional treatment to prevent visual disability and reduced quality of life,” Weinreb concluded.

The study, “Association Between Ganglion Cell Complex Thinning and Vision-Related Quality of Life in Glaucoma,” was published in JAMA Ophthalmology.