Visual impairment in older adults because of age-related macular degeneration (AMD), but not glaucoma, in older adults was associated with restriction of travel to nearby locations, according to a study by Frank C. Curriero, Ph.D., of the Johns Hopkins Bloomberg School of Public Health, Baltimore, and colleagues.

Visual impairment is known to affect mobility but an unstudied aspect of visual impairment is whether patients restrict their travel to places near home because of it, which can lead to a more isolated life and a greater inability to access necessary services, according to the study background.

Researchers used cellular tracking devices to record the travel patterns of 61 control participants with normal vision, 84 patients with glaucoma and bilateral visual field loss, and 65 patients with AMD with bilateral or severe unilateral loss of visual acuity (VA). Participants' locations were tracked every 15 minutes between 7 a.m. and 11 p.m. for seven days. The study measured the average the maximum distance from home and the average maximum span of travel.

In patients with AMD compared with control group participants, the average excursion size and span decreased by about one-quarter mile for VA loss defined as loss of the ability to read each additional line of an eye chart. Similar, but statistically insignificant associations, were observed between glaucoma patients and control group participants, according to the results.

"Reduced mobility resulting from vision loss may lead to difficulties in performing daily activities, but also to loss of travel outside the home," the study concludes.