Association of Vision Impairment and Major Eye Diseases With Mobility and Independence in a Chinese Population.

Abstract

Mobility limitations arising from vision impairment (VI) can result in loss of independence and reduced quality of life. However, few data are available on the association between VI and mobility limitations at a population-based level, particularly in Asian populations. To assess the association of VI and major eye diseases with mobility and independence (M&I) in a Chinese population. The Singapore Chinese Eye Study (February 9, 2009, to December 19, 2011) was a population-based, cross-sectional study of 3353 persons aged 40 to 80 years of Chinese ethnicity. Patients underwent visual acuity testing, and sociodemographic and medical data were collected from standardized questionnaires. Data analysis for this study was performed October 2015 to April 2016. Presenting bilateral visual acuity (categorized as none, moderate, or severe VI) and major eye diseases (cataract, uncorrected refractive error, glaucoma, age-related macular degeneration, and diabetic retinopathy). Patients answered questions on the M&I scale of the Impact of Vision Impairment questionnaire, validated using Rasch analysis. The composite M&I score (score range, -4.47 to 7.48 logits; higher scores indicate better M&I) and 11 individual item scores were the main outcomes. The association between bilateral VI and eye conditions and the composite and individual M&I item scores was assessed using linear regression models. Of the 3353 patients, the mean (SD) age was 59.7 (9.9) years, and 1662 (49.6%) were male. The mean (SD) presenting visual acuity values in the better and worse eyes were 0.20 (0.21) and 0.39 (0.42) logMAR, respectively. A total of 1432 patients (42.7%) and 114 patients (3.4%) had moderate and severe bilateral VI, respectively. Mobility and independence systematically worsened as the severity of bilateral VI increased. There was a clinically meaningful reduction in M&I (20%; β, -1.44; 95% CI, -1.75 to -1.13) and all 11 M&I tasks in patients with severe bilateral VI compared with no VI. Glaucoma (13%; β, -0.94; 95% CI, -1.82 to -0.06) and cataract (6%; β, -0.43; 95% CI, -0.65 to -0.22) were independently associated with worse M&I, with patients with glaucoma particularly concerned about avoiding falling or tripping. Bilateral VI in this population was associated with substantial decrements in M&I, with glaucoma and cataract independently associated with worse M&I. Although these associations do not prove that preventing bilateral VI will improve M&I in this population, the results suggest that such interventions could be of tremendous value from this perspective.