Predominantly Persistent IRF in nAMD Eyes Linked to Worse Long-Term Visual Acuity

Gui-shuang Ying, PhD

Approximately one-quarter of eyes with neovascular age-related macular degeneration (nAMD) had predominantly persistent intraretinal fluid (PP-IRF) through year 2 in the Comparison of Age-related Macular Degeneration Treatment Trials (CATT).

The data suggest PP-IRF through year 1 was associated with worse long-term visual acuity, but the relationship disappeared after adjustment for baseline predictors of visual acuity.

“Predominantly persistent intraretinal fluid through year 2 was independently associated with worse long-term visual acuity and scar development,” wrote study author Gui-shuang Ying, PhD, Center for Preventive Ophthalmology and Biostatistics, Perelman School of Medicine, University of Pennsylvania.

The study investigators aimed to describe PP-IRF and its association with visual acuity and retinal anatomic findings at long-term follow-up in eyes treated with pro re nata (PRN) ranibizumab or bevacizumab for nAMD in the CATT trial.

The presence of intraretinal fluid on optical coherence tomography (OCT) scans were assessed at baseline and monthly follow-up visits by the Duke OCT Reading Center. The investigators further defined predominantly persistent IRF through week 12, year 1, and year 2 as the presence of IRF at the baseline and in ≥80% of follow-up visits.

For eyes with baseline IRF, a comparison was performed between the mean visual acuity scores (letters) and changes from the baseline in eyes with and without PP-IRF. The adjusted mean visual acuity scores and changes from the baseline were calculated using linear regression analysis to account for baseline patient features identified as predictors of visual acuity in previous CATT studies.

The main outcomes were identified as PP-IRF through week 12, year 1, and year 2 as well as visual acuity score and visual acuity changes, and scar development at year 2. Outcomes were adjusted for concomitant predominantly persistent subretinal fluid.

Of 363 eyes with baseline IRF included in the study, 108 (29.8%) had PP-IRF through year 1 and 95 (26.1%) had PP-IRF through year 2.

In a comparison of eyes with PP-IRF through year 1 to those without PP-IRF, the mean 1-year visual acuity score was 62.4 and 68.5, respectively (P = .002) and 65.0 and 67.4, respectively (P = .13) after adjustment.

Then, PP-IRF through year 2 was associated with worse adjusted 1-year mean visual acuity scores (64.8 vs. 69.2; P = .006) and change (4.3 vs. 8.1; P = .01) as well as worse adjusted 2-year mean VA scores (63.0 vs 68.3; P = .004) and changes (2.4 vs 7.1; P = .009).

Moreover, PP-IRF through year 2 was associated with a higher 2-year risk of scar development (adjusted hazard ratio, 1.49; P = .03).

The study, “Predominantly Persistent Intraretinal Fluid in the Comparison of Age-Related Macular Degeneration Treatments Trials,” was published in Ophthalmology Retina.