Patients may ameliorate their glaucoma with exercise, diet, and other lifestyle choices.
After poring over the literature, Yvonne Ou, MD, assistant professor of ophthalmology, University of California, San Francisco, gives her patients advice about physical activity, positions to avoid, leafy green vegetables, caffeine, and blood pressure treatment.
“We know that aerobic exercise lowers intraocular pressure (IOP),” Dr. Ou said. “This has been well studied.”
The prescription may prove challenging, since studies have shown that patients with greater visual field loss perform less physical activity. One study showed the number of steps per day decreased as the visual field mean deviation worsened.
In mice, exercise appears to protect against optic nerve damage. In one experiment, researchers subjected mice to an IOP elevation of 50 mm HG for 30 minutes and put them in a tank of water, forcing them to swim for 60 minutes a day, 5 days a week.
Electroretinograms showed that exercise reversed damage caused by the IOP surge in older mice. Exercise produced its benefits not only if it was administered before the injury, but if it was administered afterward. In a related experiment, levels of brain-derived neurotrophic factor, which enhances neuron growth, were maintained in mice that exercised.
Given this evidence, Dr. Ou tells patients to “get moving, especially if you aren’t already. This can be as simple as the easier habits, such as just getting out for a walk. Even if patients are mobility-impaired, the more they can get up from a sitting position the better.”