Declining patterns of physical activity related to visual field damage
At worse levels of visual field damage, patients with glaucoma perform less physical activity across episodes of brief activity, according to a study presented at the virtual Association for Research in Vision and Ophthalmology meeting.
“Physical activity is a central feature of well-being and an essential component of quality of life,” Jian-Yu E, MD, MPH, said. Given that 5,000 steps per day are the minimum goal for a healthy life, they can be achieved in multiple ways, concentrated or fractioned.
“What matters is not only the total amount, the type and intensity of activity, but also the fragmentation and diurnal pattern, basically when the main activity occurs,” he said.
Activity fragmentation and diurnal patterns, and their correlation with visual field (VF) damage, were investigated in the study population of the Falls in Glaucoma Study, a 3-year project at Johns Hopkins University. Mean participant age was 70 years, the majority of subjects had at least two comorbidities, and 45% used five or more prescription medications.
VF damage was categorized as normal/mild (n = 116), moderate (n = 96) and severe (n = 25). Participants wore accelerometers (Actical, Philips Respironics) for 1 week to estimate the total active minutes per day and the number of activity bouts per day. Activity fragmentation was calculated by the sum of active bouts divided by the sum of active minutes per day.
“More fragmented daily activity and less active time per day were correlated with greater levels of VF damage, roughly a 2% increase of fragmentation index and less active time per five-unit (dB) decrement in [integrated visual field] sensitivity. Participants with more severe VF damage spent 68 fewer active minutes per day compared with those with normal or mild VF damage,” Jian-Yu said.
The number of active bouts was comparable across groups. However, higher fragmentation values reflect shorter and more fractured bouts of activity, he said.
“Tailored physical activity regimens may be needed to restore normal patterns of activity,” Jian-Yu said.
Jian-Yu E, et al. Patterns of daily physical activity across the spectrum of visual field damage in glaucoma. Presented at: Association for Research in Vision and Ophthalmology meeting; May 6, 2020 (virtual meeting).