Relationships between retinal structure and function and vision-related quality of life measures in advanced age-related macular degeneration.

Purpose To evaluate the association between ophthalmic structure/function measures and five standardized quality of life (QoL) instruments, in patients with advanced age-related macular degeneration (AMD). Methods We examined 20 AMD patients (ages 66-93 years) recruited from the Canberra Hospital Ophthalmology Department. Visual function measures included low and high contrast visual acuity (LCVA and HCVA) and measures from 10-2 Matrix visual fields (VF). Optical coherence tomography (OCT) quantified central retinal thickness (CRT), average macular thickness (AT), and retinal nerve fibre layer thickness (RNFL). The QoL instruments were the macular degeneration-related quality of life (MacDQoL), the National Eye Institute Visual Functioning Questionnaire (VFQ), its two face-recognition questions (A6 and 11), and the Geriatric Depression Scale (GDS). Pearson correlations, Canonical Correlation Analysis (CCA), and cross-validated stepwise-regression were used to examine the relationships between structure/function measures and the QoL instruments. Results The selected models for the five instruments had R2 ranging from 0.65 ± 0.12 to 0.90 ± 0.05 (mean ± SD) and median F-statistics > 188. HCVA was strongly associated with all QoL except the GDS, for which CRT, AT and RNFL figured highly. RNFL was most important for MacDQoL, and 2nd for VFQ question-A6. Centrally weighted VF measures were rarely selected but global VF measures were common, especially for the overall NEI-VFQ questionnaire. CCA revealed that the structure/function measures and QoL instruments contained 2 statistically independent mechanisms. Conclusions In patients with advanced AMD, CRT and HCVA were strong determinants of QoL instruments in AMD patients.