Abstract
Purpose :
Real-world physical activity patterns in monocular persons have not been previously characterized. This study uses a nationally representative sample to compare the physical activity levels of functionally monocular to binocularly sighted persons in the United States.
Methods :
This cross-sectional study uses data from the 2003-2004 and 2005-2006 National Health and Nutrition Examination Survey (NHANES) to compare differences in physical activity between functionally monocular and binocular participants. Functionally monocular is defined as visual acuity of better than 20/200 in one eye and 20/200 or worse in the other eye after auto-refraction. The main outcome measures were accelerometer-measured mean steps per day and mean daily minutes of moderate or vigorous physical activity (MVPA). Statistical analysis was conducted using multivariable negative binomial regression models, which included age, gender, race/ethnicity, better-eye visual acuity, educational attainment, and obesity as covariates. Sample weights were used according to guidelines from the National Center from Health Statistics.
Results :
7,967 NHANES participants had complete visual acuity and accelerometer data. The mean age at baseline was 44.5 years, and a majority were Caucasian (73%) and female (52%). In unadjusted analysis, functionally monocular participants (n=102) took fewer steps (7,254 vs 10,012, p<0.01) and engaged in fewer minutes of MVPA (13.6 vs 26.8, p<0.01) per day compared to binocularly-sighted participants (n=7,846). When adjusted for age and better-eye visual acuity, however, these between-group differences were not statistically significant. These results may be explained by the age disparity between groups: the mean age of the monocular group was 65.5 (CI 50.8-70.2) compared to the binocular group, which was 44.2 (CI 43.2-45.3). In our final model, monocular participants took 17% fewer steps per day (p=0.15) and engaged in 26% fewer minutes per day of MVPA (p=0.12).
Conclusions :
Functionally monocular persons have similar physical activity levels compared to those with binocular eyesight in the United States. Additional work is needed to determine if particular types of activity are impacted by monocular status, and if the timing of vision loss has an impact on activity levels.
This is a 2021 ARVO Annual Meeting abstract.