Greater Physical Activity Is Associated with Slower Visual Field Loss in Glaucoma

Purpose: To determine the association between physical activity levels and the rate of visual field (VF) loss in glaucoma. Design: Longitudinal, observational study. Participants: Older adults with suspect or manifest glaucoma. Methods: Participants wore accelerometers for 1 week to define average steps per day, minutes of moderate-to-vigorous activity, and minutes of nonsedentary activity. All available VF measurements before and after physical activity assessment were retrospectively analyzed to measure rates of VF loss. Main Outcome Measures: Pointwise changes in VF sensitivity associated with physical activity measures. Results: A total of 141 participants (mean age, 64.9 +/- 5.8 years) were enrolled. Eye mean deviation (MD) at the time of physical activity assessment was -6.6 decibels (dB), and average steps per day were 5613 +/- 3158. The unadjusted average rate of VF loss as measured by pointwise VF sensitivity was 0.36 dB/year (95% confidence interval, -0.37 to -0.35). In multivariable models, slower VF loss was observed for patients demonstrating more steps (+0.007 dB/year/1000 daily steps, P<0.001), moremoderate-to-vigorous activity (+0.003 dB/year/10 more minutes of moderate-to-vigorous activity per day, P<0.001), and more nonsedentary activity (+0.007 dB/year/30 more minutes of nonsedentary time per day, P = 0.005). Factors associated with a faster rate of VF loss included older age, non-white race, glaucoma surgery, cataract surgery, and moderate baseline VF damage (-6dB >= MD > -12dB) asopposedto mild VF damage (MD > -6 dB). Similar associations between baseline accelerometer-measured physical activity and rates of VF loss were observed over other time periods (e.g., within 1, 3, and 5 years of activity assessment). Conclusions: Increased walking, greater time spent doing moderate-to-vigorous physical activity, and more time spent in nonsedentary activity were associated with slower rates of VF loss in a treated population of patients with glaucoma, with an additional 5000 daily steps or 2.6 hours of nonsedentary physical activity decreasing the average rate of VF loss by approximately 10%. Future prospective studies are needed to determine if physical activity can slow VF loss in glaucoma or if progressive VF loss results in activity restriction. If the former is confirmed, this would mark physical activity as a novel modifiable risk factor for preventing glaucoma damage. (C) 2018 by the American Academy of Ophthalmology