OCT Risk Factors for Development of Late Age-Related Macular Degeneration in the Fellow Eyes of Patients Enrolled in the HARBOR Study

Abstract

Purpose: To evaluate the relationship between OCT features and progression to late age related-macular degeneration (AMD) in the fellow eyes of patients enrolled in the Study of Ranibizumab Administered Monthly or on an As-needed Basis in Patients With Subfoveal Neovascular AMD (HARBOR) (ClinicalTrials.gov identifier, NCT00891735).

Design: Post hoc analysis of a phase 3 multicenter, prospective, randomized, double-masked, active treatment-controlled clinical trial.

Participants: Evaluable patients (n = 501) with macular neovascularization (MNV) secondary to neovascular AMD and early or intermediate AMD in the fellow eye.

Methods: Volume OCT scans from 501 fellow eyes of 501 patients with MNV were reviewed. Baseline OCT features that were assessed included intraretinal hypereflective foci (IHRF), hyporeflective foci (hRF) within drusenoid lesions (DLs), subretinal drusenoid deposits (SDDs), and drusen volume (DV) of 0.03 mm³ or more. OCT images obtained at months 6, 12, 18, and 24 were graded by masked graders for late AMD (defined as MNV, complete retinal pigment epithelium and photoreceptor atrophy [cRORA], or both). Participant demographic characteristics (age, gender, and smoke exposure) and baseline OCT features were correlated with progression to late AMD.

Main outcome measures: Incidence of late AMD, hazard ratio (HR) for demographics, and OCT risk factors.

Results: At month 24, 33.13% of eyes (166/501) demonstrated late AMD: 20.96% (105/501) demonstrated cRORA, whereas 12.18% (61/501) demonstrated MNV. Baseline demographic factors were not associated significantly with development of late AMD, whereas significant associations were identified for all OCT features. Intraretinal hypereflective foci had an HR of 5.21 (95% confidence interval [CI], 3.29-8.26), hRF within DLs had an HR of 2.42 (95% CI, 1.74-3.38), SDD had an HR of 1.95 (95% CI, 1.34-2.82), and DV of 0.03 mm³ or more had an HR of 1.46 (95% CI, 1.03-2.07). The correlation remained significant when considering only the progression to cRORA and MNV alone, except for DV, which was not associated significantly with progression to MNV.

Conclusions: We confirmed that 4 previously reported OCT risk factors were associated with progression to late AMD in the fellow eyes of patients newly diagnosed with MNV. Although outcomes of more than 2 years were not evaluated, these findings may help to identify high-risk AMD patients.