Using Uniocular Visual Acuity Substantially Underestimates the Impact of Visual Impairment on Quality of Life Compared with Binocular Visual Acuity.

PURPOSE: Although the impact of vision-related quality of life (VRQoL) is assessed optimally using binocular visual acuity (VA), uniocular VA remains the preferred measurement method in clinic-based and epidemiologic studies. We compared the impact of distance presenting binocular VA and uniocular VA in the better-seeing (better-eye VA) and worse-seeing (worse-eye VA) eye on VRQoL. DESIGN: The Singapore Chinese Eye Study 2 (2015-2017), a population-based, cross-sectional study. PARTICIPANTS: One thousand eight hundred twenty-two individuals (mean age, 66.2 years [standard deviation, 8.9 years]; 51.1% women) were included. METHODS: Presenting uniocular VA and binocular VA were assessed using a logarithm of the minimum angle of resolution number chart at a distance of 4 m under standard lighting by trained and certified study optometrists. Multiple linear regression models were constructed to determine the independent associations between binocular VA, better-eye VA, and worse-eye VA and the outcome (VRQoL), adjusted for potential confounders, including age, gender, socioeconomic status, and presence of comorbidities. In addition, a cluster sandwich estimator was used to determine if any differences in ß estimates between the associations were statistically significant. MAIN OUTCOME MEASURES: Vision-related quality of life was measured using Rasch-transformed scores from the emotional, mobility, and reading domains of the Impact of Visual Impairment (IVI) questionnaire. RESULTS: Although every 2-line increase (worsening) in binocular VA and uniocular VA was associated independently with decrements in emotional, mobility, and reading IVI scores (P < 0.05 for all), the reductions in all VRQoL domains were substantially lower (P < 0.1) when using either the better-eye VA (compared with binocular VA ß-estimates, -27.8%, -19.4%, and -24.2% difference in emotional, mobility, and reading IVI scores, respectively) or worse-eye VA (compared with binocular VA ß estimates, -38.9%, -58.1%, and -57.5% reduction in emotional, mobility, and reading IVI scores, respectively) to quantify vision loss. CONCLUSIONS: Uniocular VA seems to underestimate the impact of vision loss on VRQoL indices compared with binocular VA. Our data suggest that researchers, clinicians, and policy planners should consider using binocular instead of uniocular measures of VA in patient-reported outcome evaluation of vision loss because it may better reflect its impact on VRQoL.

Impact of Incidence and Progression of Diabetic Retinopathy on Vision-Specific Functioning.

PURPOSE: To investigate the independent impact of the incidence and progression of diabetic retinopathy (DR) on visual functioning (VF). DESIGN: Population-based cohort study. PARTICIPANTS: A total of 518 participants aged 40 to 80 years (baseline visit 2007-2009 and second visit 6 years later, 2013-2015), with diabetes, clinical data, and VF information at both visits. MAIN OUTCOME MEASURES: VF-7 scores, converted to interval-level person measures (in logits) using Rasch analysis. METHODS: Incident DR was defined using the Modified Airlie House classification as "none or minimal" DR at baseline and at least mild nonproliferative DR at follow-up; incident vision-threatening DR (VTDR; severe nonproliferative DR, proliferative DR, and/or clinically significant macular edema) as no VTDR at baseline, and present at follow-up; and DR progression as at least a 1-step worsening in DR at follow-up from mild or worse status at baseline. The longitudinal associations between incident DR, VTDR, and DR progression, as well as change in composite and individual item scores of VF, were assessed using multivariable linear regression models. RESULTS: Of the 518 participants (mean age ± standard deviation [SD] 59.8±9.0 years; 47.7% female), 42 (9.8%), 14 (2.8%), and 32 (42.7%) had incident DR, incident VTDR, and DR progression, respectively, at follow-up. In models adjusting for traditional confounders, persons with incident DR and VTDR had a 13.7% (ß = -0.60; 95% confidence interval [CI], -0.96 to -0.24; P = 0.001) and 23% (ß = -1.00; 95% CI, -1.61 to -0.38; P = 0.001) reduction in mean VF scores at follow-up. Furthermore, individuals with incident DR had similar independent reductions in scores for 7 individual items of the VF-7, whereas those with incident VTDR had the largest reductions for activities like cooking (31%; P = 0.003), reading the newspaper (29.6%; P < 0.001), and seeing street signs (28%, P = 0.001) at follow-up. Progression of DR was not independently associated with change in overall VF (ß = -0.18; 95% CI, -1.00, 0.64; P = 0.660). CONCLUSIONS: Incident DR, particularly vision-threatening stages, has a substantial negative impact on people's overall vision-dependent functioning and specific activities such as cooking, seeing street signs, and reading the newspaper. Our findings reinforce the need for strategies to prevent or delay the development of DR.

Prevalence, Correlates, and Impact of Uncorrected Presbyopia in a Multiethnic Asian Population.

PURPOSE: To examine the prevalence, correlates, and impact of uncorrected presbyopia on vision-specific functioning (VF) in a multiethnic Asian population. DESIGN: Population-based cross-sectional study. METHODS: We included 7890 presbyopic subjects (3909 female; age range, 40-86 years) of Malay, Indian, and Chinese ethnicities from the Singapore Epidemiology of Eye Disease study. Presbyopia was classified as corrected and uncorrected based on self-reported near correction use. VF was assessed with the VF-11 questionnaire validated using Rasch analysis. Multivariable logistic and linear regression models were used to investigate the associations of sociodemographic and clinical parameters with uncorrected presbyopia, and its impact on VF, respectively. As myopia may mitigate the impact of noncorrection, we performed a subgroup analysis on myopic subjects only (n = 2742). RESULTS: In total, 2678 of 7890 subjects (33.9%) had uncorrected presbyopia. In multivariable models, younger age, male sex, Malay and Indian ethnicities, presenting distance visual impairment (any eye), and lower education and income levels were associated with higher odds of uncorrected presbyopia (all P < .05). Compared with corrected presbyopia, noncorrection was associated with worse overall VF and reduced ability to perform individual near and distance vision-specific tasks even after adjusting for distance VA and other confounders (all P < .05). Results were very similar for myopic individuals. CONCLUSION: One-third of presbyopic Singaporean adults did not have near correction. Given its detrimental impact on both near and distance VF, public health strategies to increase uptake of presbyopic correction in younger individuals, male individuals, and those of Malay and Indian ethnicities are needed.