Longitudinal relationships between visual acuity and severe depressive symptoms in older adults: the Salisbury Eye Evaluation study

Objectives: To assess the longitudinal relationship between visual acuity (VA) and depressive symptoms (DSs) among older adults.

Methods: A population-based sample of 2520 white and black individuals aged 65–84 years in 1993--1995 was assessed at baseline and at two, six, and eight years later. Presenting and best-corrected VA was assessed using early treatment diabetic retinopathy study chart. DSs were assessed using the severe depression subscale of General Health Questionnaire 28. Latent growth curve models estimated VA and DS trajectories and age-adjusted associations between trajectories.

Results: Best-corrected logMAR VA worsened over time (slope = 0.026, intercept = 0.013, both p < 0.001). No change in DS over time was observed (slope = ?0.001, p = 0.762; intercept = 1.180, p < 0.001). However, a small change in DS was observed in participants who completed all rounds (slope = 0.005, p = 0.015). Baseline VA levels correlated with baseline DS levels (r = 0.14, p < 0.001). Baseline DS was associated with best-corrected VA change (r = 0.17, p = 0.01). Baseline best-corrected VA was not associated with DS change (r = 0.017, p = 0.8). Best-corrected VA change was not significantly associated with DS change (r = ?0.03, p = 0.7).

Discussion: DSs are significantly associated with VA cross-sectionally, and persons with higher baseline DS scores were more likely to experience worsening VA over time. The complex relationship between visual impairment and DS suggests the need for a continued effort to detect and treat both visual decline and severe DSs in a growing elderly population.